Category Archives: Techniques

General microbiology and science, July 7

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Metagenomics binning based on co-abundance, bias in Illumina sequencing, and lots of metabolomics.

Phages and viruses

Bacteriophage-based synthetic biology for the study of infectious diseases – Robert J Citorik – Current Opinion in Microbiology

“Here, we discuss bacteriophage-based technologies and their application to the study of infectious diseases. “

Sequencing and Metagenomics

Identification and assembly of genomes and genetic elements in complex metagenomic samples without using reference genomes – H Bjørn Nielsen (and 142 other authors) – Nature Biotechnology

“Here we present a method, based on binning co-abundant genes across a series of metagenomic samples, that enables comprehensive discovery of new microbial organisms, viruses and co-inherited genetic entities and aids assembly of microbial genomes without the need for reference sequences.”

Evaluating bias of Illumina-based bacterial 16S rRNA gene profiles – Katherine Kennedy – Applied and Environmental Microbiology

“In this study, we tested the effects of template concentration, pooling of PCR amplicons, and sample preparation/inter-lane sequencing on the reproducibility associated with paired-end Illumina sequencing of bacterial 16S rRNA genes.”

Next generation sequencing technology: Advances and applications – HPJ Buermans, JT den Dunnen – Biochimica et Biophysica Acta (BBA) – Molecular Basis of Disease

“In this chapter we review the technical background of the different commercially available NGS platforms with respect to template generation and the sequencing reaction and take a small step towards what the upcoming NGS technologies will bring.”

Systems biology as an approach for deciphering microbial interactions – Puneet Kumar Singh – Briefings in Functional Genomics

“Here, we endeavor to summarize, epigrammatic description of sophisticated techniques and software that provides an enhanced understanding of metagenomics data analysis. “

Metabolomics

Stronger findings for metabolomics through Bayesian modeling of multiple peaks and compound correlations – Tommi Suvitaival – Bioinformatics

“We propose a hierarchical Bayesian model for inferring
differences between groups of samples more accurately in
metabolomic studies, where the observed compounds are collinear.”

Emergent Biosynthetic Capacity in Simple Microbial Communities – Hsuan-Chao Chiu – PLOS Computational Biology

“Here we present a comprehensive computational framework, integrating high-quality metabolic models of multiple species, temporal dynamics, and flux variability analysis, to study the metabolic capacity and dynamics of simple two-species microbial ecosystems.”

Metabolomics Analysis Identifies Intestinal Microbiota-Derived Biomarkers of Colonization Resistance in Clindamycin-Treated Mice – Robin L. P. Jump – PLOS ONE

“Clindamycin treatment caused marked changes in metabolites present in fecal specimens. Of 484 compounds analyzed, 146 (30%) exhibited a significant increase or decrease in concentration during clindamycin treatment followed by recovery to baseline that coincided with restoration of in vivo colonization resistance.”

Volatile Organic Compounds as Novel Markers for the Detection of Bacterial
Infections – Mohsen Sohrabi – Clinical Microbiology

“The possibility of using VOCs markers as one of the largest groups of bacterial metabolites would open a new frontier for developing more efficient techniques in the diagnosis of bacterial infections.”

The importance of sulfur-containing metabolites in discriminating fecal extracts between normal and type 2 diabetic mice – Alesia Walker – Journal of Proteome Research

“We demonstrate that a metabolic disorder such as T2DM affects the gastrointestinal tract environment thereby influencing different metabolic pathways and their respective metabolites in diabetic mice. “

Microarrrays

Applications of Phylogenetic Microarrays to Profiling of Human Microbiomes (PDF) -Oleg Paliy and Vijay Shankar – Book chapter

“This chapter will focus on currently available phylogenetic microarrays for the inter- rogation of human-associated microbiota, the technologies used to construct the arrays, as well as several key features that distinguish them from other approaches. “

Arsenic metabolism

Infant toenails as a biomarker of in utero arsenic exposure – Matthew A Davis – Journal of Exposure Science and Environmental Epidemiology

“In a sample of 170 mother–infant pairs from New Hampshire, we determined infant exposure to in utero arsenic by evaluating infant toenails as a biomarker using inductively coupled plasma mass spectrometry. “

Chromosomal organization

Spatial confinement is a major determinant of the folding landscape of human chromosomes – Gamze Gürsoy – Nucleic Acids Research

“Here we describe a model called constrained self-avoiding chromatin (C-SAC) for studying spatial structures of chromosomes, as the available space is a key determinant of chromosome folding. “

Bacteria in the news

The bacteria has been decimated: how much should we care what words used to mean? – By Tom Chivers – Telegraph

“Much amusement this morning on the Today programme, as John Humphrys shamefacedly confessed to having said “a bacteria” on the previous day’s episode.”

Yoghurt industry blamed for encouraging bacteria – The Daily Mash

“One day massive cow-sized bacteria will rule the world and they will kill everyone who doesn’t like special yoghurts.”

When Scientists Experiment on Themselves: H. pylori and Ulcers – By Hanno Charisius – Scientific American

“With his famous self-experiment, Marshall was able to demonstrate that Helicobacter pylori bacteria can cause acute gastritis which in turn may cause ulcers. He had asked neither an ethics commission nor his wife for permission to conduct this experiment. “

In rental cars, dangerous bacteria may come along for the ride – Jeff Rossen and Josh Davis, Today

“Armed with gloves and goggles, they swabbed every car from top to bottom: the steering wheels, gearshifts, door handles, even the GPS units.”

Bacteria that ‘eats’ odour could bring end to smelly toilets in China – Stephen Chen – South China Morning Post

“Mainland scientists have developed a “bioweapon” that can wipe out the notorious bad smell in public toilets. Up to 75 per cent of the odour can be removed, with the rest suppressed by a natural, pleasant fragrance, according to researchers with the Chinese Academy of Sciences.”

Marine Mammals

Some SeaWorld mammals survive longer in captivity – Mike Schneider – Associated Press

“Breakthroughs in training and medicine that allow the parks’ medical staffs to perform far fewer stressful or invasive procedures are partly responsible for those successes, SeaWorld officials said.”

Science and publishing

Highly cited Researchers 2014 – Thomson Reuters

“Over three thousand researchers earned the distinction by writing the greatest numbers of reports officially designated by Essential Science Indicators℠ as Highly Cited Papers—ranking among the top 1% most cited for their subject field and year of publication, earning them the mark of exceptional impact.”

Dr. Bik’s Picks

Rats use their whiskers in a similar way to how humans use their hands and fingers – Science Daily

“Rats deliberately change how they sense their environment using their facial whiskers depending on whether the environment is novel, if there is a risk of collision and whether or not they can see where they are going.”

Giraffe legs’ strong, skinny secret – Victoria Gill – BBC Science

“Scientists have worked out the anatomical secret to giraffes’ long and spindly – but strong – legs.”

Environmentalists Almost Killed My Friend – Josh Bloom – Science 2.0

“It is hysteria-producing nonsense like this that leads any non-scientist to conclude that we are systematically being poisoned every day. “

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General microbiology and science digest, July 2

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Genome assembly, metabolomics of Salmonella infection, a brief history of women in science (but in Nature!), and Nature’s retraction of the STAP papers.

Metagenomics

Screen Shot 2014-07-02 at 10.13.28 PMBayesian Genome Assembly and Assessment by Markov Chain Monte Carlo Sampling – Mark Howison – PLOS ONE

“We present a Markov chain Monte Carlo approach to sequence assembly that instead generates distributions of assembly hypotheses with posterior probabilities, providing an explicit statistical framework for evaluating alternative hypotheses and assessing assembly uncertainty. “

Infection and host response

Screen Shot 2014-07-02 at 10.14.12 PMSalmonella Typhi and Salmonella Paratyphi – A elaborate distinct systemic metabolite signatures during enteric fever – Elin Näsström – eLife

“To investigate metabolite signals associated with enteric fever we performed two dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC/TOFMS) on plasma from patients with S. Typhi and S. Paratyphi A infections and asymptomatic controls, identifying 695 individual metabolite peaks.”

and: Host-pathogen interactions: Honing in on enteric fever – Lyle R McKinnon, Quarraisha Abdool Karim – eLife

“The use of metabolomics could lead to improved diagnostics for enteric fever. “

Screen Shot 2014-07-02 at 10.14.58 PMHuman Genetic Variation and Yellow Fever Mortality during 19th Century U.S. Epidemics – Lauren E Blake, Mariano A Garcia-Blanco – mBio

“Caucasians diagnosed with YF were 6.8 times more likely to succumb than non-Caucasians with the disease. No other major causes of death during the 19th century demonstrated a similar mortality skew toward Caucasians. “

Bacterial and viral detection in clinical samples

Screen Shot 2014-07-02 at 10.15.58 PMThe Microbial Detection Array for Detection of Emerging Viruses in Clinical Samples – A Useful Panmicrobial Diagnostic Tool – Maiken W. Rosenstierne – PLOS ONE

“We report a modified Whole Transcriptome Amplification (WTA) method that increases unbiased amplification, particular of RNA viruses.”

The Sooner, The Better – Nicholette Zeliadt – The Scientist

“New approaches to diagnosing bacterial infections may one day allow the identification of pathogens and their antibiotic susceptibility in a matter of hours or minutes.”

Screen Shot 2014-07-02 at 10.16.45 PMReview: Biosensors for Whole-Cell Bacterial Detection – Asif Ahmed – Clinical Microbiology Reviews

” In this review, we discuss recent progress in the use of biosensors for the detection of whole bacterial cells for sensitive and earlier identification of bacteria without the need for sample processing.”

Screen Shot 2014-07-02 at 10.17.23 PMIsolation of Microorganisms Using Sub-Micrometer Constrictions – Nil Tandogan – PLOS ONE

“We present an automated method for isolating pure bacterial cultures from samples containing multiple species that exploits the cell’s own physiology to perform the separation.”

Phages and viruses

Screen Shot 2014-07-02 at 10.18.17 PMFour Escherichia coli O157:H7 Phages: A New Bacteriophage Genus and Taxonomic Classification of T1-Like Phages – Yan D. Niu – PLOS ONE

“Comparative genomic, proteomic and phylogenetic analysis suggested that the four phages along with 17 T1-like phage genomes from database of National Center for Biotechnology Information (NCBI) can be assigned into a proposed subfamily “Tunavirinae” with further classification into five genera”

Dengue

Screen Shot 2014-07-02 at 10.18.45 PMClinical and Virological Descriptive Study in the 2011 Outbreak of Dengue in the Amazonas, Brazil – Valquiria do Carmo Alves Martins – PLOS ONE

“The aim of the study was to describe the clinical epidemiology of dengue in Manaus, the capital city of the state of the Amazonas, where all the four DENV serotypes were co-circulating simultaneously.”

Phylogeny and taxonomy

Screen Shot 2014-07-02 at 10.12.14 PMComparative Genomics of the Bacterial Genus Streptococcus Illuminates Evolutionary Implications of Species Groups – Xiao-Yang Gao – PLOS ONE

“We use comparative genomic approaches to yield a better understanding of the evolution of Streptococcus through genome dynamics, population structure, phylogenies and virulence factor distribution of species groups. “

Screen Shot 2014-07-02 at 10.12.46 PMLivestock-Associated MRSA Carriage in Patients without Direct Contact with Livestock – Miranda M. L. van Rijen – PLOS ONE

“Fifty-six individuals (20.7%) without animal contact carried MC398. In hospitals with high pig-densities in the adherence area, the proportion of MC398 of all MUO was higher than this proportion in hospitals without pigs in the surroundings.”

 Arsenic metabolism

Screen Shot 2014-07-02 at 10.02.56 PMMichigan’s arsenic problem is among the worst in the nation. Here’s why that matters – Rebecca Williams – Michigan Radio

“If you’re on city water, your drinking water has to comply with a federal regulation that limits the amount of arsenic in it, but if you’re on a private well, the federal and state governments do not limit the amount of arsenic in your well.”

Women in Science

Screen Shot 2014-07-02 at 9.59.45 PMWomen in science: A temporary liberation – Patricia Fara – Nature

“The First World War ushered women into laboratories and factories. In Britain, it may have won them the vote, argues Patricia Fara, but not the battle for equality.”

Science and Ethics

Nature Editorial: STAP retracted – Nature

“This week, Nature publishes retractions of two high-profile papers that claimed a major advance in the field of stem cells… We — research funders, research practitioners, institutions and journals — need to put quality assurance and laboratory professionalism ever higher on our agendas, to ensure that the money entrusted by governments is not squandered, and that citizens’ trust in science is not betrayed.”

Dr. Bik’s Picks

Screen Shot 2014-07-02 at 10.11.31 PMPLOS ONE Publishes its 100,000th Article – Damian Pattinson – PLOS Blogs

“PLOS ONE publishes its 100,000th article – a pretty major milestone for a journal that has seen its fair share of momentous events, and a perfect opportunity to reflect on this journey.”

Screen Shot 2014-07-02 at 10.08.37 PMLeprosy, Still Claiming Victims – Natalie Angier, New York Times

““I’m absolutely convinced that leprosy must be thought of as a genetic disease as well as an infectious one,” Dr. Schurr said. In the end, he added wryly, “understanding it may help cure diseases of rich people, too.””

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General microbiome digest, July 1

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Diet and gut microbiome (again), Campylobacter in chicken is not a commensal, microbiomes of fish, insects, corals, plant, and hospitals, and women in science.

Human gut microbiome

Screen shot 2014-07-01 at 06.07PM, Jul 01Correlation network analysis reveals relationships between diet-induced changes in human gut microbiota and metabolic health – T Kelder – Nutrition & Diabetes

“We assessed fecal microbiota composition and host response patterns of metabolic and inflammatory markers in 10 apparently healthy men subjected to a high-fat high-caloric diet (HFHC, 1300 kcal/day extra) for 4 weeks. “

Pregnancy and birth

Screen shot 2014-07-01 at 06.08PM, Jul 01 1Gestational Age and Age at Sampling Influence Metabolic Profiles in Premature Infants
Reese H. Clark – Pediatrics

“Metabolic profiles (15 amino acids and 35 acylcarnitines) were obtained by using standard newborn techniques on infants born between 23 and 31 completed weeks of gestation.”

Screen shot 2014-07-01 at 06.08PM, Jul 01Non-invasive analysis of intestinal development in preterm and term infants using RNA-Sequencing – Jason M. Knight – Nature Scientific Reports

“we have developed a novel, noninvasive, molecular approach that utilizes next generation RNA sequencing on stool samples containing intact epithelial cells for the purpose of quantifying intestinal gene expression.”

Screen shot 2014-07-01 at 06.09PM, Jul 01Cesarean Section and Rate of Subsequent Stillbirth, Miscarriage, and Ectopic Pregnancy: A Danish Register-Based Cohort Study – Sinéad M. O’Neill – PLOS Medicine

“This study found that cesarean section is associated with a small increased rate of subsequent stillbirth and ectopic pregnancy.”

Bird microbiome

Screen shot 2014-07-01 at 06.10PM, Jul 01Campylobacter jejuni Is Not Merely a Commensal in Commercial Broiler Chickens and Affects Bird Welfare – Suzanne Humphrey – mBio

“Through experimental infection of four commercial breeds of broiler chickens, we show that breed has a significant effect on C. jejuni infection and the immune response of the animals, although these factors have limited impact on the number of bacteria in chicken ceca. “

Fish microbiome

Screen shot 2014-07-01 at 06.10PM, Jul 01 1Quorum quenching bacteria Bacillus sp. QSI-1 protect zebrafish (Danio rerio) from Aeromonas hydrophila infection – Weihua Chu – Nature Scientific Reports

“In this study, the effect of Bacillus sp. QSI-1 as an efficient quorum quencher on virulence factors production and biofilm formation of fish pathogen Aeromonas hydrophila was investigated. ”

Insect microbiome

Screen shot 2014-07-01 at 06.11PM, Jul 01Evolutionary origin of insect–Wolbachia nutritional mutualism – Naruo Nikoh – PNAS

“In the bedbug’s Wolbachia genome, we identified a gene cluster encoding the complete synthetic pathway for biotin (vitamin B7), which is not present in other Wolbachia genomes and is presumably acquired via lateral transfer from a coinfecting endosymbiont. “

Corals and sponges microbiome

Screen shot 2014-07-01 at 06.12PM, Jul 01Local genomic adaptation of coral reef-associated microbiomes to gradients of natural variability and anthropogenic stressors – Linda W. Kelly – PNAS

“The present study investigated the community structure and metabolic potential of microbes inhabiting coral reefs located across an extensive area in the central Pacific. “

Plant microbiome

Screen shot 2014-07-01 at 06.13PM, Jul 01The role of sulfur and phosphorus mobilizing bacteria in biochar induced growth promotion of Lolium perenne – A Fox – FEMS Microbiology Ecology

“16S rRNA gene based rhizobacteria community analysis revealed a significant biochar treatment effect. Abundance of nematodes feeding on bacteria was also significantly increased in the biochar treatments.”

Functional diversification within bacterial lineages promotes wide functional overlapping between taxonomic groups in a Mediterranean soil forest – J Curiel Yuste – FEMS Microbiology Ecology

“We investigated the relationship between taxonomy and functioning of soil bacterial communities in soils from a Mediterranean Holm-oak forest using a high throughput DNA pyrosequencing technique. “

Soil, sewage and sludge microbiome

Screen shot 2014-07-01 at 06.15PM, Jul 01Response of soil-associated microbial communities to intrusion of coal mine-derived acid mine drainage – Justin S Brantner and John M Senko – Environmental Science & Technology

” Evaluation of pyrosequencing-derived 16S rRNA gene sequences recovered from incubations revealed the development of microbial community characteristics that were similar to those of the mature iron mound sediment. “

Transformation Products and Human Metabolites of Triclocarban and Triclosan in Sewage Sludge Across the United States – Benny F. G. Pycke – Environmental Science & Technology

“Here, we report on the levels of eight transformation products, human metabolites, and manufacturing byproducts of TCC and TCS in raw and treated sewage sludge.”

Built Environment Microbiome

Screen shot 2014-07-01 at 06.14PM, Jul 01Rethinking Sterile: The Hospital Microbiome – Carrie Arnold – Environ Health Perspect

“Gilbert, an environmental microbiologist at Argonne National Laboratory, and his platoon of graduate students, postdocs, and research assistants descended on the hospital several times each day, even before it opened to the public. Armed with cotton swabs, they focused their efforts on the floors devoted to surgery and oncology. “

Bioinformatics

Screen shot 2014-07-01 at 06.15PM, Jul 01 1A cloud-compatible bioinformatics pipeline for ultrarapid pathogen identification from next-generation sequencing of clinical samples – Samia N. Naccache – Genome Research

“Here we describe SURPI (“sequence-based ultrarapid pathogen identification”), a computational pipeline for pathogen identification from complex metagenomic NGS data generated from clinical samples, and demonstrate use of the pipeline in the analysis of 237 clinical samples comprising more than 1.1 billion sequences. “

Metagenomics

Metagenomic scaffolds enable combinatorial lignin transformation
Cameron R. Strachan – PNAS

“In this study, we devised a previously unidentified biosensor responsive to lignin transformation products. We used this biosensor in a functional screen to recover metagenomic scaffolds sourced from coal bed bacterial communities. “

Arsenic metabolism

Sealing rice field boundaries in Bangladesh: a pilot study demonstrates reductions in water use, arsenic loading to field soils, and methane emissions from irrigation water – Rebecca B Neumann – Environmental Science & Technology

“Irrigation of rice fields in Bangladesh with arsenic-contaminated and methane-rich groundwater loads arsenic into field soils and releases methane into the atmosphere. We tested the water-savings potential of sealing field bunds (raised boundaries around field edges) as a way to mitigate these negative outcomes.”

Localised Flux-Maxima of Arsenic, Lead and Iron around Root Apices in Flooded Lowland Rice – Paul Nicholas Williams – Environmental Science & Technology

“Here we use new diffusive gradients in thin-film (DGT)/planar optode sandwich sensors deployed in situ on rice roots to demonstrate a new geochemical niche of greatly enhanced As, Pb and Fe(II) mobilization into solution immediately adjacent to the root tips characterized by O2 enrichment and low pH. “

Dengue

Screen shot 2014-07-01 at 06.16PM, Jul 01Baicalin, a metabolite of baicalein with antiviral activity against dengue virus – Ehsan Moghaddam – Nature Scientific Reports

“Here, we examined the anti-DENV properties of baicalin in vitro, and described the inhibitory potentials of baicalin at different steps of DENV-2 (NGC strain) replication.”

Antibiotic resistance

Review: The expression of antibiotic resistance genes in antibiotic-producing bacteria – Stefanie Mak – Molecular Microbiology

“Antibiotic-producing bacteria encode antibiotic resistance genes that protect them from the biologically active molecules that they produce. The expression of these genes needs to occur in a timely manner: either in advance of or concomitantly with biosynthesis. It appears that there have been at least two general solutions to this problem. “

General microbiology

Screen shot 2014-07-01 at 06.20PM, Jul 01Bacterial sugar utilization gives rise to distinct single-cell behaviors – Taliman Afroz – Molecular Microbiology

“Here, we performed single-cell analyses to probe the behavior of representative pathways in the model bacterium Escherichia coli. “

Identification of essential Alphaproteobacterial genes reveals operational variability in conserved developmental and cell cycle systems – Patrick D. Curtis and Yves V. Brun – Molecular Microbiology

“These results show that while essential cell functions are conserved across varying genetic distance, much of a given organism’s essential gene pool is specific to that organism.”

Science and career

Screen shot 2014-07-01 at 06.22PM, Jul 01Elite male faculty in the life sciences employ fewer women – Jason M. Sheltzer and Joan C. Smith – PNAS

“To explore the current causes of women’s underrepresentation in biology, we collected publicly accessible data from university directories and faculty websites about the composition of biology laboratories at leading academic institutions in the United States. “

Screen shot 2014-07-01 at 06.01PM, Jul 01Americans Think We Have the World’s Best Colleges. We Don’t. – Kevin Carey – New York Times

“We see K-12 schools and colleges differently because we’re looking at two different yardsticks: the academic performance of the whole population of students in one case, the research performance of a small number of institutions in the other.”

Dr. Bik’s picks

Screen shot 2014-07-01 at 06.23PM, Jul 01Herbivore diet breadth mediates the cascading effects of carnivores in food webs – Michael S. Singer – PNAS

“Accounting for phylogenetic nonindependence of herbivores and plants, we show for the first time (to our knowledge) that dietary specialization of herbivore species is associated with reduced bird predation across an herbivore phylogeny, and that dietary specialization of herbivores increases the antipredator effects of camouflage and aposematism.”

Screen shot 2014-07-01 at 06.23PM, Jul 01 1Evolution of the ribosome at atomic resolution – Anton S. Petrov – PNAS

“Comparing eukaryotic and prokaryotic ribosomes allows us to identify 3D insertion fingerprints of the expansion segments. Similar fingerprints allow us to analyze the common core and detect ancestral expansion segments within it. “

Plastic mapPlastic debris in the open ocean – Andrés Cózar – PNAS

“In this work, we synthetize data collected across the world to provide a global map and a first-order approximation of the magnitude of the plastic pollution in surface waters of the open ocean.”

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General microbiology and science, June 24

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Metabolomics, metagenomics, phages in the human gut, arsenic poisoning in China, and a big award for Dengue research.

Metabolomics

Metaproteomics: Extracting and Mining Proteome Information to Characterize Metabolic Activities in Microbial Communities – Paul E. Abraham – Current Protocols in Bioinformatics

“In this article, we provide an overview of current bioinformatic approaches and software implementations in metaproteome studies in order to highlight the key considerations needed for successful implementation of this powerful community-biology tool. “

Review: The human volatilome: volatile organic compounds (VOCs) in exhaled breath, skin emanations, urine, feces and saliva – Anton Amann – Journal of Breath Research

“Fecal volatiles have been implicated in differentiating certain infectious bowel diseases such as Clostridium difficile, Campylobacter, Salmonella and Cholera. They have also been used to differentiate other non-infectious conditions such as irritable bowel syndrome and inflammatory bowel disease.”

Metagenomics and DNA structure

Sequencing the Strange Communities: Taking on Metagenomics – Aaron Krol – Bio-IT World

““Communities are made up of organisms that interact,” says Jonathan Eisen, a professor at the School of Medicine and the College of Biological Sciences at the University of California, Davis. “They’re not made up of short reads of Illumina sequences. And we need to stitch those together into organisms in order to make useful predictions, and interpretation of experimental data.””

Gene positioning and genome function – Nidhi Vishnoi, Jie Yao – Frontiers in Biology

” In this review, we discuss some recent findings as well as experimental tools to investigate subnuclear gene positioning and to explore its implications in genome functions.”

Phages and viruses

Classification and quantification of bacteriophage taxa in human gut metagenomes – Alison S Waller – ISME Journal 

“Using taxon-specific marker genes, we identified and monitored 20 viral taxa in 252 human gut metagenomic samples, mostly at the level of genera. “

Techniques

Enzymatic Treatment of Specimens before DNA Extraction Directly Influences Molecular Detection of Infectious Agents – Pablo Goldschmidt – PLOS ONE

“The goal of the present work was to assess the efficiency of enzymatic pretreatments on infectious agents to make DNA available for further extraction and amplification.”

Dengue

Sustainable Sciences Institute (SSI) Awarded $1 Million to Battle Growing Threat to Global Public Health: Mosquito-borne Dengue Virus – PR Web

“SSI, a San Francisco nonprofit founded by Eva Harris, UC Berkeley Professor of Infectious Disease and Vaccinology and former MacArthur “Genius” award winner, has worked to minimize the threat of potentially fatal Dengue disease for 15 years. With the latest award of $1 million dollars, Harris and other SSI investigators will be able to extend their reach and speed up their efforts.”

Infection and host response

Early MicroRNA Expression Profile as a Prognostic Biomarker for the Development of Pelvic Inflammatory Disease in a Mouse Model of Chlamydial Genital Infection – Laxmi Yeruva – mBio

“To determine if chemokine and cytokine production within 24 h of infection is associated with the outcome of pathology, levels of 15 chemokines and cytokines were measured. “

Immunity to gastrointestinal nematodes: mechanisms and myths – Richard K. Grencis – Immunological Reviews

“This review aims to discuss the recent discoveries in both host protection and immunoregulation against gastrointestinal nematodes, placing the data in context of the specific life cycles imposed by the different parasites studied and the future challenges of considering the mucosal/immune axis to encompass host, parasite, and microbiome in its widest sense.”

Tailored immunity at mucosae – Yasmine Belkaid – Immunological Reviews

“This issue of Immunological Reviews presents articles from investigators involved in the exploration of the mechanisms by which mucosal barrier sites induce and control innate and adaptive immune responses.”

Detection of bacteria in blood and other sites

Rapid Detection of Enterobacteriaceae Producing Extended Spectrum Beta-Lactamases Directly From Positive Blood Cultures by Matrix-Assisted Laser-Desorption-Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) – Marina Oviaño – Clinical Microbiology and Infection

“In the assay, 141 blood cultures were tested, 13 out of them were real bacteremias and 128 corresponded to blood culture bottles seeded with bacterial clinical isolates. Bacteremias were analyzed by MALDI-TOF after a positive growth result and the 128 remaining blood cultures 24 hours after the bacterial seeding. “

General microbiology and ecology

The quest for a unified view of bacterial land colonization – Hao Wu – ISME Journal

“Here, we perform comprehensive analyses based on a large variety of bacteria by integrating taxonomic, phylogenetic and metagenomic data, in the quest for a unified view that elucidates genomic, evolutionary and ecological dynamics of the marine progenitors in adapting to nonaquatic environments. “

Lateral transfer of eukaryotic ribosomal RNA genes: an emerging concern for molecular ecology of microbial eukaryotes – Akinori Yabuki – ISME Journal

“Two distinct sequences of the 18S rRNA gene were detected from a clonal culture of the stramenopile, Ciliophrys infusionum. One was clearly derived from Ciliophrys, but the other gene originated from a perkinsid alveolate.”

Arsenic metabolism

Arsenic Pollution Sows Despair in Chinese Cancer Village (slideshow)- Yahoo News

“Xiong Demin could not have foreseen that the mine he worked at for 32 years would leave his home village poisoned and hundreds of residents, including himself and his wife, stricken with cancer.”

Dr. Bik’s Picks – Evolution Edition

Molecular Phylogeny, Biogeography, and Habitat Preference Evolution of Marsupials – Kieren J. Mitchell – Molecular Biology and Evolution

“We use 101 mitochondrial genomes and data from 26 nuclear loci to reconstruct a dated phylogeny including 97% of extant genera and 58% of modern marsupial species”

Parallel sites implicate functional convergence of the hearing gene prestin among echolocating mammals – Zhen Liu – Molecular Biology and Evolution

“By functional assays, we show that a key parameter of prestin function, 1/α, is increased in all echolocating mammals and that the N7T parallel substitution accounted for this functional convergence. Moreover, another parameter, V1/2, was shifted toward the depolarization direction in a toothed whale, the bottlenose dolphin (Tursiops truncatus) and a constant-frequency bat, Stoliczka’s trident bat (Aselliscus stoliczkanus). “

Evolutionary developmental transcriptomics reveals a gene network module regulating interspecific diversity in plant leaf shape – Yasunori Ichihashi – PNAS

“Utilizing the natural variation in leaf morphology between tomato and two related wild species, we identified a gene network module that leads to a dynamic rewiring of interactions in the whole leaf developmental gene regulatory network. “

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General microbiology and science, June 23

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Amplification of 18S rRNA genes, metabolomics, phages, and the scientific way to cut a cake.

Bacteria are everywhere

This article is citing a study that was published in 1992, not sure why they reporting about it now, but here it is:
Earpieces can multiply bacteria 11 times in ear – Tribune

“Besides concerns about deafness, there are also issues regarding use of earpieces and bacteria. A study which measured bacteria levels on audio headsets provided on commercial airline flights entitled “Changes in the microbial flora of airline headset devices after their use,” published in the journal, The Laryngoscope, brings interesting conclusions. “

Anti-bacterial bag-for-life could prevent rise in food poisoning when 5p plastic bag charge comes into force – Independent UK

“Paul Morris, the managing director, said: “Multi-use bags which can carry raw meat one week and vegetables or clothing the next is a concern of many industry experts; this bag provides a solution to the problem.””

Amplification and sequencing techniques 

Investigating Microbial Eukaryotic Diversity from a Global Census: Insights from a Comparison of Pyrotag and Full-Length Sequences of 18S rRNA Genes – Alle A. Y. Lie – Applied and Environmental Microbiology

“Operational taxonomic units (OTUs) derived from full-length (Sanger sequencing) and pyrotag (454 sequencing of the V9 hypervariable region) sequences of 18S rRNA genes from 10 global samples were analyzed in order to compare the resulting protistan community structures and species richness. “

Targeted and Highly Multiplexed Detection of Microorganisms by Employing an Ensemble of Molecular Probes – Weihong Xu – Applied and Environmental Microbiology

“To profile the microbial diversity in environmental and clinical samples, we have devised and employed molecular probe technology, which detects and identifies bacteria that do and do not grow in culture.”

Metabolomics and mass spectrometry

This one is published by the not-so-trustworthy Omics group, but it sounds interesting:
Optimisation of Sample Preparation for Direct SPME-GC-MS Analysis of Murine and Human Faecal Volatile Organic Compounds for Metabolomic Studies (links to PDF)
– Reade S – Analytical & Bioanalytical Techniques

“We evaluated different aspects of sample preparation when processing murine and human faecal samples through a pipeline involving solid phase micro-extraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS)”

Shigella reroutes host cell central metabolism to obtain high-flux nutrient supply for vigorous intracellular growth – David Kentner – PNAS

“Here, we show that infected host cells maintain normal central metabolism for energy production and host cell survival. However, Shigella captures the entire host metabolism output and degrades it further to acetate.”

Beyond the Matrix-Assisted Laser Desorption Ionization (MALDI) Biotyping Workflow: in Search of Microorganism-Specific Tryptic Peptides Enabling Discrimination of Subspecies – Maria-Theresia Gekenidis – Applied and Environmental Microbiology

“Here, it is shown that combining tryptic digestion of the acid/organic solvent extracted (classical biotyping preparation) and resolubilized proteins, nano-liquid chromatography (nano-LC), and subsequent identification of the peptides by MALDI-tandem TOF (MALDI-TOF/TOF) mass spectrometry increases the discrimination power to the level of subspecies.”

Phages and viruses

Modeling the Infection Dynamics of Bacteriophages in Enteric Escherichia coli: Estimating the Contribution of Transduction to Antimicrobial Gene Spread –
Victoriya V. Volkova – Applied and Environmental Microbiology

“Using the model and the most liberal assumptions about transduction efficiency and resistance gene frequency, we approximated the upper numerical limits (“worst-case scenario”) of gene transfer through specialized and generalized transduction in E. coli by enteric coliphages when the transduced genetic segment is picked at random. “

Tolerance of a Phage Element by Streptococcus pneumoniae Leads to a Fitness Defect during Colonization – Hilary K. DeBardeleben – Journal of Bacteriology

“Here, we examined a clinical isolate that carries a novel prophage element, designated Spn1, which was detected in both integrated and episomal forms. Surprisingly, both lytic and lysogenic Spn1 genes were expressed under routine growth conditions.”

Comparison of Five Bacteriophages as Models for Viral Aerosol Studies – Nathalie Turgeon – Applied and Environmental Microbiology

“The presence of viruses in collected air samples was detected by culture and quantitative PCR (qPCR). Our results showed that these selected five phages behave differently when aerosolized and sampled. “

Microbial detection in blood and normally sterile sites

Molecular revolution in the diagnosis of microbial brain abscesses – AK Mishra – European Journal of Clinical Microbiology & Infectious Diseases

“This article reviews the applications of the currently available tools for the etiological diagnosis of a brain abscess.”

General microbiology

Nitrogen stress response and stringent response are coupled in Escherichia coli – Daniel R. Brown – Nature Communications

“Here, we show that transcription of relA, a key gene responsible for the synthesis of ppGpp, is activated by NtrC during nitrogen starvation.”

Stenotrophomonas comparative genomics reveals genes and functions that
differentiate beneficial and pathogenic bacteria – Peyman Alavi – BMC Genomics

“We used comparative genomics as well as transcriptomic and physiological approaches to detect significant borders between the Stenotrophomonas strains: the multi-drug resistant pathogenic S. maltophilia and the plant-associated strains S. maltophilia R551-3 and S. rhizophila DSM14405T (both are biocontrol agents)”

Emergence of bacterial vortex explained – Science Daily

“When a bunch of B. subtilis bacteria are confined within a droplet of water, a very strange thing happens. The chaotic motion of individual swimmers spontaneously organizes into a swirling vortex, with bacteria on the outer edge of the droplet moving in one direction while those on the inside move the opposite direction. “

Dr. Bik’s Picks

Screen Shot 2014-06-23 at 11.53.49 PMScientists tie social behavior to activity in specific brain circuit – Stanford University

“The new findings, published June 19 in Cell, may throw light on psychiatric disorders marked by impaired social interaction such as autism, social anxiety, schizophrenia and depression, said the study’s senior author, Karl Deisseroth, MD, PhD, a professor of bioengineering and of psychiatry and behavioral sciences. “

Scientists use X-rays to look at how DNA protects itself from UV light – Science Daily

“The molecular building blocks that make up DNA absorb ultraviolet light so strongly that sunlight should deactivate them — yet it does not. Now scientists have made detailed observations of a ‘relaxation response’ that protects these molecules, and the genetic information they encode, from UV damage.”

Cut your cake and keep it (fresh), too – Eliza Barclay – NPR

““The ordinary method of cutting out a wedge is very faulty,” wrote Sir Francis Galton, a British mathematician, in a 1906 letter to the journal Nature concerning the scientific principles of cake-cutting.”

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Human microbiome, June 23

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Lactobacillus feeding on human milk, Mycoplasma in preterm birth, and Clostridium difficile infection and gut microbiota.

Pregnancy and birth

Screen Shot 2014-06-23 at 10.51.26 PMA unique gene cluster for the utilization of the mucosal and human milk-associated glycans galacto-N-biose and lacto-N-biose in Lactobacillus casei – Gonzalo N. Bidart – Molecular Microbiology

“The data represent the first characterization of novel metabolic pathways for human milk oligosaccharides and glycoconjugate structures in Firmicutes”

Screen Shot 2014-06-23 at 11.01.13 PMReport from AANP 2014, Nashville, Tennessee: Screening for Bacteria May Help Pregnancy Outcomes – Ed Susman, MedpageToday

“In a single-center study, about 70% of symptomatic women who were screened for vaginal infections with either Mycoplasma Genitalium or Mycoplasma Hominis experienced preterm birth compared with 30% of the asymptomatic women who still underwent screening for the infections at a prenatal visit, reported Allison Phillips, DNP, of Robert Morris University in Pittsburgh, and colleagues.”

Oral microbiome

Screen Shot 2014-06-23 at 10.52.34 PMNew analysis reveals previously ‘hidden diversity’ of mouth bacteria – MBL

“Using a novel computational method called oligotyping, developed by MBL Assistant Research Scientist A. Murat Eren, scientists analyzed gene sequence data from nine sites in the oral cavity. ” “The study will be published in PNAS Online Early Edition the week of June 23-27, 2014”, but is not yet on PNAS website

Screen Shot 2014-06-23 at 10.53.35 PMEffects of pH and Lactate on Hydrogen Sulfide Production by Oral Veillonella spp. – Jumpei Washio – Applied and Environmental Microbiology

“Thus, in the present study, the H2S-producing activity of growing cells, resting cells, and cell extracts of oral Veillonella species and the effects of oral environmental factors, including pH and lactate, were investigated.”

Gut microbiome

Screen Shot 2014-06-23 at 10.54.40 PMStructural and functional changes in the gut microbiota associated to Clostridium difficile infection – Ana E. Pérez-Cobas – Frontiers in Microbiology

“Here, we analyze the composition and functional differences in the gut microbiota of C. difficile infected (CDI) versus non-infected patients, both patient groups having been treated with AB therapy. To do so we used 16S rRNA gene and metagenomic 454-based pyrosequencing approaches. “

Screen Shot 2014-06-23 at 10.58.40 PMThe HLA-DQ2 genotype selects for early intestinal microbiota composition in infants at high risk of developing coeliac disease – M Olivares – Gut

“Infants with a high genetic risk had significantly higher proportions of Firmicutes and Proteobacteria and lower proportions of Actinobacteria compared with low-risk infants.”

(Both human and animal)
Screen Shot 2014-06-23 at 10.57.57 PMA single genus in the gut microbiome reflects host preference and specificity – A Murat Eren – The ISME Journal

“In our dataset of 57 M sequence reads of the V6 region of the 16S ribosomal RNA gene in samples collected from seven host species, we identified 200 high-resolution taxonomic units within Blautia using oligotyping.”

Screen Shot 2014-06-23 at 10.57.04 PMMicrobiomes are true to type – Andrew H. Moeller and Howard Ochman – PNAS

“Enter Wang et al. (3), who provide both retrospective and experimental evidence that the maintenance of enterotypes in host populations is driven by dietary variation.”

General human microbiome

Screen Shot 2014-06-23 at 10.56.07 PMMicrobiota and neurodevelopmental windows: implications for brain disorders
– Yuliya E Borre – Trends in Molecular Medicine

“This review compares the parallel early development of the intestinal microbiota and the nervous system.”

Animal models of human microbiome

Screen Shot 2014-06-23 at 11.00.16 PMThe murine appendiceal microbiome is altered in spontaneous colitis and its pathological progression – Sultan Alkadhi – Gut Pathogens

“The appendiceal dysbiosis observed in our Winnie mice is commensurate with, and adds to extant literature data. The presence of Helicobacteraceae (Proteobacteria) only in colitic Winnie mice (but not control mice) is consistent with reports of increased Helicobacter in IBD patients. “

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General microbiology and science, June 19

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How to store your sputum samples, how LPS gets inserted into the outer membrane, and why pigs have an even number of toes.

Techniques in microbiome research

Screen Shot 2014-06-19 at 11.16.59 PMTime between sputum sample collection and storage significantly influences bacterial sequence composition from Cystic Fibrosis respiratory infections – Leah Cuthbertson – Journal of Clinical Microbiology

“Aliquots were stored at room temperature before freezing at -80°C for increasing intervals up to 72 hour period. Samples were treated with propidium monoazide, to distinguish live from dead cells, prior to DNA extraction, and 16S rRNA gene pyrosequencing was used to characterise the bacterial composition.”

General microbiology

Screen Shot 2014-06-19 at 11.26.58 PMStructural basis for outer membrane lipopolysaccharide insertion – Haohao Dong – Nature

“Here we report the first crystal structure of the unique integral membrane LPS translocon LptD–LptE complex….These findings not only help us to understand important aspects of bacterial outer membrane biogenesis, but also have significant potential for the development of novel drugs against multi-drug resistant pathogenic bacteria.”

Immunology

Screen Shot 2014-06-19 at 11.13.17 PMTeaching the immune system “self” respect and tolerance – Lucienne Chatenoud – Science

“Tolerance is what we would like to restore to cure such disabling diseases. Kasagi et al. (2) indicate that it may be possible to teach the immune system to tolerate “self” again.”

Screen Shot 2014-06-19 at 11.15.42 PMIn Vivo–Generated Antigen-Specific Regulatory T Cells Treat Autoimmunity Without Compromising Antibacterial Immune Response – Shimpei Kasagi – Science

“These antigen-specific Treg cells specifically ameliorated autoimmunity without compromising immune responses to bacterial antigen. We have thus successfully generated antigen-specific Treg cells with therapeutic activity toward autoimmunity”

Phages, viruses, CRISPRs

Screen Shot 2014-06-19 at 11.18.44 PMHaloarcula hispanica CRISPR authenticates PAM of a target sequence to prime discriminative adaptation – Ming Li – Nucleic Acids Research

Science and ethics

Cheating common, say Brazil’s students – Jack Grove – Times Higher Education

“Of a sample of 47 papers published last year, 29 showed signs of word-by-word plagiarism, seven contained self-plagiarism, three had “mosaic plagiarism” (otherwise known as “synonym substitution”) and one exhibited signs of collusion.”

Dr. Bik’s Picks

Screen Shot 2014-06-19 at 11.23.10 PMThe Dangers Of Data Mining – Tommaso Dorigo – Science 2.0

“On my first day at the Erice School of Science Journalism this past week I attended a lecture by Alessio Cimarelli, who discussed “When Data Journalism meets Science: a “Hackathon””.”

Screen Shot 2014-06-19 at 11.32.23 PMEvolutionary biology: Why cattle, pigs are even-toed – Science Daily

“During their evolution, the basic limb skeletal structure was significantly modified such that today’s hippopotami have four toes, while the second and fifth toe face backwards in pigs.”

 

U.S. Says 75 Government Scientists Possibly Exposed To Live Anthrax – Reuters – Huffington Post

“The potential exposure occurred after researchers working in a high-level biosecurity laboratory at the agency’s Atlanta campus failed to follow proper procedures to inactivate the bacteria.”

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Human microbiome, June 19

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The journal Immunity has a special with several great papers on (gut) microbiome and diet. And even Martha Stewart is writing about the microbiome! In style, of course.

Oral microbiome

Screen Shot 2014-06-19 at 10.50.07 PMMining the Mouth’s Many Microbes – Tracy Vence – The Scientist

““The whole world passes through the oral cavity,” said Purnima Kumar, an assistant professor of periodontology at the Ohio State University College of Dentistry. This makes investigating the microbial communities present in the mouth a challenge.”

Gut microbiome

Screen Shot 2014-06-19 at 10.49.36 PMFinding the Missing Links among Metabolites, Microbes, and the Host – Pieter C. Dorrestein – Immunity

“Here, we provide our perspective on these connections and outline a systematic research program that could turn these individual links into a broader network that allows us to understand how these components interact. “

Screen Shot 2014-06-19 at 10.51.41 PMMining the Human Gut Microbiota for Effector Strains that Shape the Immune System – Philip P. Ahern – Immunity

“Here, we discuss a scalable, less biased approach for identifying effector strains in complex microbial communities that impact immune function. The approach begins by identifying uncultured human fecal microbiota samples that transmit immune phenotypes to germ-free mice.”

Screen Shot 2014-06-19 at 10.51.09 PMDiet, Metabolites, and “Western-Lifestyle” Inflammatory Diseases – Alison N. Thorburn – Immunity

“This review highlights what is currently known about diet, metabolites, and their associated immune pathways in relation to the development of inflammatory disease.”

Screen Shot 2014-06-19 at 10.52.28 PMInflammatory Bowel Disease as a Model for Translating the Microbiome – Curtis Huttenhower – Immunity

“IBD thus represents perhaps the most comprehensive current model for understanding the human microbiome’s role in complex inflammatory disease. Here, we review the influences of the microbiota on IBD and its potential for translational medicine.”

Screen Shot 2014-06-19 at 10.54.48 PMCulturomics and pyrosequencing evidence of the reduction in gut microbiota diversity in patients with broad-spectrum antibiotics – Grégory Dubourg – International Journal of Antimicrobial Agents

“Culturomics was performed on four stool samples from patients treated with large-scale antibiotics to assess the diversity of their gut flora in comparison with other culture-dependent studies. Pyrosequencing of the V6 region was also performed and was compared with a control group.”

Screen Shot 2014-06-19 at 10.55.24 PMLong-term monitoring of the human intestinal microbiota from the 2nd week to 13 years of age – Akihito Endo – Anaerobe

“Few long term follow-up studies have been reported and we therefore characterized the development of intestinal microbiota of ten subjects from the 2nd week of life to 13 years of age. PCR-denaturing gradient gel electrophoresis combined with several bacterial group-specific primer sets demonstrated the colonization steps of defined bacterial groups in the microbiota”

Respiratory microbiome

Time between sputum sample collection and storage significantly influences bacterial sequence composition from Cystic Fibrosis respiratory infections – Leah Cuthbertson – Journal of Clinical Microbiology

“Aliquots were stored at room temperature before freezing at -80°C for increasing intervals up to 72 hour period. Samples were treated with propidium monoazide, to distinguish live from dead cells, prior to DNA extraction, and 16S rRNA gene pyrosequencing was used to characterise the bacterial composition.”

Screen Shot 2014-06-19 at 10.46.12 PM

Human Pharyngeal Microbiome May Play a Protective Role in Respiratory Tract Infections – Zhancheng Gao – Genomics, Proteomics & Bioinformatics

“Recent studies have demonstrated that the pharyngeal microbiome comprises an abundance of bacterial species that interact with the local epithelial and immune cells, and together, they form a unique micro-ecological system.”

Skin and wounds microbiology

Screen Shot 2014-06-19 at 10.57.13 PMMicrobial profiling of combat wound infection through detection microarray and next-generation sequencing – Nicholas A. Be – Journal of Clinical Microbiology

“We employed a microarray capable of detecting all sequenced pathogens for interrogation of 124 wound samples from extremity injuries in combat-injured U.S. service members. A subset of samples was also processed via next-generation sequencing and metagenomic analysis. “

Press coverage:

Screen Shot 2014-06-19 at 11.00.07 PMHealing warriors by making a census of combat wounds’ microbiota – Melissa Healy – LA Times

“New research suggests that physicians treating future U.S. troops (and perhaps those treating some of today’s wounded warriors) may be able to take a fast and thorough census of the microorganisms living in a combat wound and tailor their treatment accordingly.”

Human microbiome in the news

Screen Shot 2014-06-19 at 10.56.06 PM4 habits for a healthy gut – Martha Stewart – CNN

“Studies also suggest that diabetic and obese patients tend to lack a diversity of bacteria, and the Cleveland Clinic found that some bacteria metabolize components of egg and meat to produce a compound that aids in the clogging of arteries.”

Screen Shot 2014-06-19 at 10.44.58 PMWebinar: The Promise of the Microbiome: Function and Dysfunction in Humans and Beyond – Science Magazine, featuring David Relman, Rob Knight, and Jack Gilbert

“During this webinar, the speakers will:

  • Provide a brief introduction to microbiomes and how they may fundamentally impact our study of the natural world
  • Share their research data on human and nonhuman microbiota, including microbe-associated environmental impacts on human health
  • Discuss the role of microbiomes in obesity and malnutrition
  • Answer your questions live during the webinar!”

Bacterial detection in blood and other sites

Screen Shot 2014-06-19 at 10.58.32 PMMassive Parallel Sequencing Provides New Perspectives on Bacterial Brain Abscesses – Øyvind Kommedal – Journal of Clinical Microbiology

“Bacterial 16S rRNA genes were amplified directly from the specimens and sequenced using Ion Torrent technology, with an average of 500,000 reads per sample. The results were compared to those from culture- and Sanger sequencing-based diagnostics.”

Animal models of microbiota

Screen Shot 2014-06-19 at 10.59.25 PMDiet-Induced Alterations in Gut Microflora Contribute to Lethal Pulmonary Damage in TLR2/TLR4-Deficient Mice – Yewei Ji – Cell Reports

“Here, we show that chronic intake of a high-fat diet (HFD), not a low-fat diet, leads to severe pulmonary damage and mortality in mice deficient in Toll-like receptors 2 and 4 (DKO).”

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General microbiology and science, June 18

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Learn about dengue at the World Cup, a deadly lake, 3D structures of genomes, OTUs and tables, musical kids, and why your iPhone headphones are always in a knot.

Dengue

Evaluation of single-round infectious, chimeric dengue type 1 virus as an antigen for dengue functional antibody assays – Atsushi Yamanaka – Vaccine

“In the present study, SRIPs of DENV-1 (D1-SRIPs) were evaluated as an antigen for functional antibody assays.”

An inhibition model of BPTI to unlinked dengue virus NS2B-NS3 protease – Hua Li – FEBS Letters

“BPTI shows strong competitive inhibitory activity (Ki = 6.5 nM) against this unlinked protease, which adopts a closed conformation.”

The role of cell proteins in dengue virus infection – Ma. Isabel Salazar – Journal of Proteomics

“This review focuses on recent reports about cellular proteins involved along the dengue virus replication cycle, in prime cellular targets during the infection of both humans and mosquito hosts and also on the proteomics and other approaches that are being used to reveal the entire orchestration and most significant processes altered during infection.”

Dengue outlook for the World Cup in Brazil – Eduardo Massad – The Lancet Infectious Diseases

Correspondence on: Dengue outlook for the World Cup in Brazil: an early warning model framework driven by real-time seasonal climate forecasts

Arsenic metabolism

43,000 die annually in Bangladesh: Study – The Daily Star

“This rate is 25 percent all over Bangladesh, said Dr Kazi Matin Ahmed, geology professor of Dhaka University. He presented the paper at a seminar titled “Arsenic Activities, Research and Outcomes” organised by the Bangladesh Medical Research Council (BMRC) in its auditorium in the capital yesterday.”

Arsenic speciation in rice-based food for adults with celiac disease – Sandra Munera-Picazo – Food Additives and Contaminants

“…the objective of this study was to analyze the occurrence of arsenic (As) in gluten-free products, basically those rice-based, intended for celiac adult consumers.”

Could This Acid Lake Hold the Elixir of Life for Cancer Patients? – Ryot.org

“The Berkeley Acid Pit is a giant hole filled with arsenic and sulfuric acid, and has a history of causing disturbing deaths… and it’s making its way into the city’s water supply, according to PitWatch.”

Chromosomal Organization

Targeted chromatin capture (T2C): a novel high resolution high throughput method to detect genomic interactions and regulatory elements – Petros Kolovos – Epigenetics &

“We applied T2C on well-known model regions, the mouse beta-globin locus and the human H19/IGF2 locus. In both cases we identified all known chromatin interactions”

A statistical approach for inferring the 3D structure of the genome – Nelle Varoquaux – Bioinformatics

“We propose a novel approach to infer a consensus 3D structure of a genome from Hi-C data. The method incorporates a statistical model of the contact counts, assuming that the counts between two loci follow a Poisson distribution whose intensity decreases with the physical distances between the loci.”

Spatial organization of interphase chromosomes and the role of chromatin fibril dynamics in the positioning of genome elements – E. S. Gushchanskaya – Molecular Biology

“In this review, we discuss the results of these projects, which allow us to explain the functional basis of nucleus multilevel compartmentalization and to identify the principles of high-level chromatin organization. “

Computational ecology

A fast and unbiased procedure to randomize ecological binary matrices with fixed row and column totals – Giovanni Strona – Nature Communications

“A well-known problem in numerical ecology is how to recombine presence-absence matrices without altering row and column totals. “

Consistent, comprehensive and computationally efficient OTU definitions – Jai Ram Rideout – PeerJ PrePrints

“We present a performance-optimized algorithm, subsampled open-reference OTU picking, for assigning marker gene (e.g., 16S rRNA) sequences generated on next-generation sequencing platforms to operational taxonomic units (OTUs) for microbial community analysis.”

 

Bacteria in blood and sterile sites

Rapid and direct MALDI-MS identification of pathogenic bacteria from blood using ionic liquid-modified magnetic nanoparticles (Fe3O4@SiO2) – Mukesh L. Bhaisare – Journal of Materials Chemistry B

“A novel method for pathogenic bacteria identification directly from blood samples using cationic ionic liquid-modified magnetic nanoparticles (CILMS) is reported.”

Metagenomics

GroopM: An automated tool for the recovery of population genomes from related metagenomes – Michael Imelfort – PeerJ PrePrints

“Here we introduce GroopM, an automated binning tool that primarily uses differential coverage to obtain high fidelity population genomes from related metagenomes. “

DNA-dependent RNA polymerase detects hidden giant viruses in published databanks – Vikas Sharma – Genome Biology and Evolution

“To explore the dark matter, we used viral RNAP2 and reconstructed putative ancestral RNAP2, which were significantly superior in detecting distant clades than current sequences, and we revealed two additional unknown mimiviruses, misclassified as an euryarchaeote and a oomycete plant pathogen, and detected unknown putative viral clades”

Metabolomics

Comparative Metabolomics and Structural Characterizations Illuminate Colibactin Pathway-Dependent Small Molecules – Maria I. Vizcaino – Journal of the American Chemical Society

“Here we implemented a comparative metabolomics and targeted structural network analyses approach to identify a catalog of small molecules dependent on the colibactin pathway from the meningitis isolate E. coli IHE3034 and the probiotic E. coli Nissle 1917.”

Scientific writing and publishing

Screen Shot 2014-06-18 at 11.01.34 PMColour blindness: Still too many red–green figures – S. Colby Allred – Nature

“People with red–green colour blindness cannot interpret figures in research papers that use these colours. We call for all journals to provide alternative versions of figures that are more accessible to such individuals.”

Open access: Sharing your data is easier than you think – Stephen Eglen – Nature

“Storing large volumes of raw data is costly, but many items destined for sharing are highly processed and relatively small. “

Dr. Bik’s Picks

The Irish potato famine pathogen Phytophthora infestans originated in central Mexico rather than the Andes – Erica M. Goss – PNAS

“We sequenced four nuclear genes in representative samples from Mexico and the South American Andes. An Andean origin of P. infestans does not receive support from detailed analyses of Andean and Mexican populations. “

Behavioral and Neural Correlates of Executive Functioning in Musicians and Non-Musicians – Jennifer Zuk – PLOS ONE

“Overall, musicians show enhanced performance on several constructs of EF, and musically trained children further show heightened brain activation in traditional EF regions during task-switching.”

There’s a scientific reason your iPhone headphones are always tangled – Fiona MacDonald – Science Alert

“But between 46 centimeters and 150 centimeters (about five feet), the probability of a knot forming rises dramatically.”

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General microbiology and science, June 17

Posted on by

How to freeze and preserve communities, host response, standardized metadata for pathogens, primers for fungal detection and more. Check out Dr. Bik’s Picks for coffee in space and sticky tongues.

Infection and host response

The effect of age on the systemic inflammatory response in patients with community-acquired pneumonia – Lonneke A. van Vught – Clinical Microbiology and Infection

“Serum concentrations of pro-inflammatory (interleukin (IL)-6 and IL-8) and anti-inflammatory cytokines (IL-10 and IL-1 receptor antagonist) did not differ between age groups, although admission IL-8 levels tended to be higher in old patients (p = 0.05). “

Clinical Disease Severity of Respiratory Viral Co-Infection versus Single Viral Infection: A Systematic Review and Meta-Analysis – Sandra A. Asner – PLOS ONE

“No differences in clinical disease severity between viral co-infections and single respiratory infections were documented.”

Standardized Metadata for Human Pathogen/Vector Genomic Sequences – Vivien G. Dugan – PLOS ONE

“The standard includes data fields about characteristics of the organism or environmental source of the specimen, spatial-temporal information about the specimen isolation event, phenotypic characteristics of the pathogen/vector isolated, and project leadership and support. “

Discovering Hidden Connections among Diseases, Genes and Drugs Based on Microarray Expression Profiles with Negative-Term Filtering – Jain-Shing Wu – PLOS ONE

“This study proposes a novel means of employing existing GEPs to reveal hidden relationships among diseases, genes, and drugs within a rich biomedical database, PubMed. Unlike the co-occurrence method, which considers only the appearance of keywords, the proposed method also takes into account negative relationships and non-relationships among keywords, the importance of which has been demonstrated in previous studies.”

MS spectrometry and microbiology

A simple, robust and rapid approach to detect carbapenemases in Gram negative isolates by MALDI-TOF mass spectrometry: validation with triple quadripole tandem mass spectrometry, microarray and PCR – Christelle Vogne – Clinical Microbiology and Infection

“Here, we developed a simple, easy and rapid MALDI-TOF-based assay to detect carbapenemases and compared this innovative test with 4 other diagnostic approaches on 47 clinical isolates. “

Source-Identifying Biomarker Ions between Environmental and Clinical Burkholderia pseudomallei Using Whole-Cell Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) – Suthamat Niyompanich – PLOS ONE

“In this present study, we employed a whole-cell MALDI-TOF MS approach for assessing its potency in clustering a total of 11 different B. pseudomallei isolates (consisting of 5 environmental and 6 clinical isolates) with respect to their origins and to further investigate the source-identifying biomarker ions belonging to each bacterial group.”

Phages and viruses

Effectiveness of bacteriophages in the sputum of cystic fibrosis patients – Emilie Saussereau – Clinical Microbiology and Infection

“The demonstration that bacteriophages infect their bacterial hosts in the sputum environment, regardless of the clinical characteristics of the patients, represents a major step towards the development of bacteriophage therapy to treat chronic lung infections.”

Standards for Sequencing Viral Genomes in the Era of High-Throughput Sequencing –
Jason T. Ladner – mBio

“Here, we propose five “standard” categories that encompass all stages of viral genome finishing, and we define them using simple criteria that are agnostic to the technology used for sequencing.”

Dengue

Dengue Serosurvey in Sint Eustatius – Teresa Leslie – PLOS ONE

“ Few studies have investigated dengue on Sint Eustatius. Blood samples were collected to determine the prevalence of antibodies against dengue in the Sint Eustatius population.”

General microbiology

Invited Editorial: Bioterrorism: myth or reality? – Gilbert Greub and Martin P. Grobusch – Clinical Microbiology and Infection

“Interestingly, while there are no doubt many features which tell those topics apart from each other, bioterrorism, in its broad sense, in its perception by the public, strikingly shares some features with the human interest in viral hemorrhagic fevers as witnessed during the recent Zaire ebolavirus disease outbreak “

Invited Editorial: New epidemiology of Staphylococcus aureus infections – Jean-Philippe Rasigade – Clinical Microbiology and Infection

“The clinical and molecular epidemiology of S. aureus infections has changed dramatically over the past two decades with the emergence of community-associated methicillin-resistant S. aureus (CA-MRSA).”

Sequencing and data analysis

Summarizing Specific Profiles in Illumina Sequencing from Whole-Genome Amplified DNA – Isheng J. Tsai – DNA Research

“To utilize the full potential of WGA to reveal the real biological interest, this article highlights the importance of recognizing additional sources of errors from amplified sequence reads and discusses the potential implications in downstream analyses.”

The Bias Associated with Amplicon Sequencing Does Not Affect the Quantitative Assessment of Bacterial Community Dynamics – Federico M. Ibarbalz – PLOS ONE

“The performance of two sets of primers targeting variable regions of the 16S rRNA gene V1–V3 and V4 was compared in their ability to describe changes of bacterial diversity and temporal turnover in full-scale activated sludge.”

HIVE-Hexagon: High-Performance, Parallelized Sequence Alignment for Next-Generation Sequencing Data Analysis – Luis Santana-Quintero – PLOS ONE

“High-performance Integrated Virtual Environment (HIVE), a cloud-based environment optimized for storage and analysis of extra-large data, presents an algorithmic solution: the HIVE-hexagon DNA sequence aligner. “

Sample preparation, primers, PCR

Optimized Cryopreservation of Mixed Microbial Communities for Conserved Functionality and Diversity – Frederiek-Maarten Kerckhof – PLOS ONE

“ In summary, we have evaluated a cryopreservation protocol that succeeded in preserving both community structure and functionality of value-added microbiomes. ”

Comparison and Validation of Some ITS Primer Pairs Useful for Fungal Metabarcoding Studies – Michiel Op De Beeck – PLOS ONE

“In the current study, three selected primer pairs were tested for their suitability as fungal metabarcoding primers.”

Chromosome organization

Assessing Diversity of DNA Structure-Related Sequence Features in Prokaryotic Genomes – Yongjie Huang and Jan Mrázek – DNA Research

“Our results show that simple sequence repeats and Z-DNA-promoting patterns are generally suppressed in prokaryotic genomes, whereas palindromes and inverted repeats are over-represented.”

Dr. Bik’s Picks

Tongue adhesion in the horned frog Ceratophrys sp. – Thomas Kleinteich & Stanislav N. Gorb- Scientific Reports

“Here we measured for the first time adhesive forces and tongue contact areas in living individuals of a horned frog (Ceratophrys sp.) against glass. We found that Ceratophrys sp. generates adhesive forces well beyond its own body weight.”

Good news: Espresso machine in SPAAAACE. Bad news: Fuelled by URINE – Simon Sharwood – The Register

“A critical issue standing between humanity and long-term residence in space has been solved after boffins invented an espresso machine they plan to send up to the International Space Station (ISS), groan-inducingly dubbed the ISSpresso.”

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