General microbiome and science, July 8

Metabolic networks, CRISPR induced immunity, and influence of extraction methods and primers on microbiome analysis. Plus some smallpox in the Lost&Found, and a big citation scandal in SAGE journals.

Microbial ecology / metabolomics

Screen Shot 2014-07-08 at 10.07.56 PMIdentifying All Moiety Conservation Laws in Genome-Scale Metabolic Networks – Andrea De Martino – PLOS ONE

“ Our method is deployed for the analysis of moiety conservation relationships in two large-scale reconstructions of the metabolism of the bacterium E. coli, in six tissue-specific human metabolic networks, and, finally, in the human reactome as a whole, revealing that bacterial metabolism could be evolutionarily designed to cover broader production spectra than human metabolism.”

Emergent

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

“We specifically focus on detecting emergent biosynthetic capacity – instances in which a community growing on some medium produces and secretes metabolites that are not secreted by any member species when growing in isolation on that same medium. “

DIET ArchaeaDirect Interspecies Electron Transfer between Geobacter metallireducens and Methanosarcina barkeri – Amelia-Elena Rotaru – Applied and Environmental Microbiology

“M. barkeri is the second methanogen found to accept electrons via DIET and the first methanogen known to be capable of using either H2 or electrons derived from DIET for CO2 reduction. “

Optimal defenseOptimal Defense Strategies in an Idealized Microbial Food Web under Trade-Off between Competition and Defense – Selina Våge – PLOS ONE

“ Under coexistence with a competition specialist, a balance of competitive and defensive ability of the defense strategist was found to be evolutionarily stable, whereas stronger defense was optimal under increased nutrient levels in the absence of the pure competition specialist.”

Microbial detection

Screen Shot 2014-07-08 at 10.13.13 PMHuman Herpes Viruses Are Associated with Classic Fever of Unknown Origin (FUO) in Beijing Patients – Weimin Zhou – PLOS ONE

“HHVs are associated with Chinese patients (especially for children) with classic FUO. Our study adds perspective to the aetiological and clinical characteristics of classic FUO in beijing patients.”

Phages and viruses

Screen Shot 2014-07-08 at 10.13.31 PMCRISPR-Induced Distributed Immunity in Microbial Populations – Lauren M. Childs – PLOS ONE

“We analyze sequence diversity of experimentally coevolving populations of Streptococcus thermophilus and their viruses where CRISPR-Cas is active, and find the rapid emergence of distributed immunity in the host population, demonstrating the importance of this emergent phenomenon in evolving microbial communities.”

Techniques

Influence of DNA Extraction Method, 16S rRNA Targeted Hypervariable Regions, and Sample Origin on Microbial Diversity Detected by 454 Pyrosequencing in Marine Chemosynthetic Ecosystems – Perrine Cruaud – Applied and Environmental Microbiology

“Thanks to statistical and diversity analyses as well as inference of operational taxonomic unit (OTU) networks, we show that (i) while DNA extraction methods do not seem to affect the results for some samples, they can lead to dramatic changes for others; and (ii) the choice of amplification and sequencing primers also considerably affects the microbial community detected in the samples.”

Dengue

Sanofi’s dengue vaccine first to complete phase 3 – Gunjan Sinha – Nature Biotechnology

“Banking on approval, Sanofi has already started production, a move some have described as a “huge gamble” in light of the vaccine’s disappointing results from earlier studies, says Mark Clark, a pharmaceuticals analyst at Deutsche Bank in London.”

Microbes in the News

Found: Forgotten Vials of Smallpox – Maryn McKenna – Wired.com (also see CDC Media Statement)

“Workers clearing out an old storage room on the Bethesda, Md. campus of the National Institutes of Health have found a forgotten box of vials that contain smallpox.”

The Bacteria That Got Spread Throughout The US By Military Testing – Esther Inglis-Arkell – IO9

“Have you ever heard of serratia marcescens bacteria? Today they are a cause of hospital infections. In the 1960s, they were secretly sprayed across Washington, San Francisco, and New York.”

Manage Your Microbes – Laura Stec – Palo Alto Online

“I’ve been researching this wonderful advance in science for Manage Your Microbes, a cook class at Belmont Library on July 29th. “

Science, Publishing, and Career

SAGE Publications busts “peer review and citation ring,” 60 papers retracted – Retraction Watch

SAGE announces the retraction of 60 articles implicated in a peer review and citation ring at the Journal of Vibration and Control (JVC). “

13 Subtle Ways Women Are Treated Differently At Work – Jenna Goudreau – Business Insider

“Both men and women hold these views but often don’t even realize it. “It’s hard to fight this,” says Rivers, but awareness is key.

Dr. Bik’s Picks

Combining colour and temperature: A blue object is more likely to be judged as warm than a red object – Hsin-Ni Ho – Nature Scientific Reports

“It is commonly believed that reddish colour induces warm feelings while bluish colour induces cold feelings. We, however, demonstrate an opposite effect when the temperature information is acquired by direct touch.”

MandarinSequencing of diverse mandarin, pummelo and orange genomes reveals complex history of admixture during citrus domestication – G Albert Wu – Nature Biotechnology

“Here we sequence and compare citrus genomes—a high-quality reference haploid clementine genome and mandarin, pummelo, sweet-orange and sour-orange genomes—and show that cultivated types derive from two progenitor species. “

[hr]

General microbiology and science, July 7

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. “

[hr]

General digest, July 3

CRISPRs, the yearly NAR Web Server issue, dengue, arsenic, and The Picks.

CRISPRs

Screen shot 2014-07-03 at 03.59PM, Jul 03 1Detection and characterization of spacer integration intermediates in type I-E CRISPR–Cas system – Zihni Arslan – Nucleic Acids Research

“We identified and characterized in Escherichia coli intermediate states of spacer integration and mapped the integration site at the chromosomal CRISPR array in vivo. “

Bioinformatics

Screen shot 2014-07-03 at 03.59PM, Jul 03Nucleic Acids Research published their yearly Web Server issue. The names of some tools alone are very entertaining (CHOPCHOP, Coffee, COGNAC, just to lists some C’s), but here are some resources that sound interesting:

Alignment-Annotator web server: rendering and annotating sequence alignments
Christoph Gille

Spaced words and kmacs: fast alignment-free sequence comparison based on inexact word matches – Sebastian Horwege

EvoCor: a platform for predicting functionally related genes using phylogenetic and expression profiles – W. James Dittmar

CFM-ID: a web server for annotation, spectrum prediction and metabolite identification from tandem mass spectra – Felicity Allen

PIQMIe: a web server for semi-quantitative proteomics data management and analysis – Arnold Kuzniar

PTHGRN: unraveling post-translational hierarchical gene regulatory networks using PPI, ChIP-seq and gene expression data – Daogang Guan

BioMet Toolbox 2.0: genome-wide analysis of metabolism and omics data – Manuel Garcia-Albornoz

deepTools: a flexible platform for exploring deep-sequencing data – Fidel Ramírez

PrecisePrimer: an easy-to-use web server for designing PCR primers for DNA library cloning and DNA shuffling – Cyrille Pauthenier

PubServer: literature searches by homology – Lukasz Jaroszewski

Arsenic metabolism

Arsenic color toolSediment color tool for targeting arsenic-safe aquifers for the installation of shallow drinking water tubewells – Mohammed Hossain – Science of the Total Environment

“Laboratory analysis of 521 groundwater samples collected from 144 wells during 2009 to 2011 indicate that As concentrations in groundwater were generally higher in the black colored sediments with an average of 239 μg/L.”

Screen shot 2014-07-03 at 03.55PM, Jul 03Arsenite stimulates glutathione export and glycolytic flux in viable primary rat brain astrocytes – Nimesha Tadepalle – Neurochemistry International

“The strong stimulation of GSH export by arsenite was prevented by MK571, an inhibitor of the multidrug resistance protein 1, suggesting that this transporter mediates the accelerated GSH export.”

Screen shot 2014-07-03 at 03.55PM, Jul 03 1Trichoderma spp. alleviate phytotoxicity in lettuce plants (Lactuca sativa L.) irrigated with arsenic-contaminated water – Antonio G. Caporale – Journal of Plant Physiology

“Plant Growth-Promoting Fungi (PGPF) of both Trichoderma species alleviated, at least in part, the phytotoxicity of As, essentially by decreasing its accumulation in the tissues and enhancing plant growth, P status and net photosynthesis rate.”

Dengue

Kwissa DengueDengue Virus Infection Induces Expansion of a CD14+CD16+ Monocyte Population that Stimulates Plasmablast Differentiation – Marcin Kwissa – Cell Host & Microbe

“Transcriptomic analysis of whole blood revealed that genes encoding proinflammatory mediators and type I interferon-related proteins were associated with high DENV levels during initial symptomatic disease. “

dengue bidetG3BP1, G3BP2 and CAPRIN1 Are Required for Translation of Interferon Stimulated mRNAs and Are Targeted by a Dengue Virus Non-coding RNA – Katell Bidet – PLOS Pathogens

“We examined three conserved host RNA-binding proteins (RBPs) G3BP1, G3BP2 and CAPRIN1 in dengue virus (DENV-2) infection and found them to be novel regulators of the interferon (IFN) response against DENV-2. “

Dengue Virus Persists in Stored Platelets and Red Blood Cells – Michael R. Sutherland – Transfusion Medicine Reviews

“…we investigated the persistence of DENV (serotypes 1-4) in stored platelet (PC) and red blood cell concentrates (RCC) under standard blood bank conditions. “

2013: Rise of the deadly dengue fever in Pakistan – Anum Wasim – Journal of Infection and Public Health

“Last year saw more than 17000 dengue cases being reported from all over the country, the highest number ever in the country’s history.”

Women in Science 

Gender: Perception differences – Nature

“Female leaders underrate how their bosses and colleagues perceive their performance, find US researchers”

Screen shot 2014-07-03 at 03.57PM, Jul 03Leader self-awareness: An examination and implications of women’s under-prediction –
Rachel E. Sturm – Journal of Organizational Behavior

“…women under-predict their bosses’ ratings of their leadership compared with men, even though they self-rate the same and are rated by their bosses similarly to men”

 

10 Words Every Girl Should Learn – Soraya Chemaly – Huffington Post

Yes! This! “A woman, speaking clearly and out loud, can say something that no one appears to hear, only to have a man repeat it minutes, maybe seconds later, to accolades and group discussion.”

Science, Publishing, and Ethics

Science Editorial: Raising the bar – Marcia McNutt – Science

“For that reason, with much help from the American Statistical Association, Science has established, effective 1 July 2014, a Statistical Board of Reviewing Editors (SBoRE), consisting of experts in various aspects of statistics and data analysis, to provide better oversight of the interpretation of observational data.”

Science ethics: Young scientists speak – Shelly Benjaminy – Science

“What is the most challenging ethical question facing young investigators in your field? How should it be addressed? In April, we asked young scientists to tell us their thoughts.“

Science and Art

Screen shot 2014-07-03 at 03.57PM, Jul 03 1Can You Guess What These Cute Pink Tiles Are Made Of? – Francie Diep – Popular Science

“These images are from research into new techniques for medical diagnoses and biometrics.”

Dr. Bik’s Picks

Screen shot 2014-07-03 at 03.51PM, Jul 03Multiple evidence strands suggest that there may be as few as 19 000 human protein-coding genes – Iakes Ezkurdia – Human Molecular Genetics

“Here, we mapped peptides detected in seven large-scale proteomics studies to almost 60% of the protein-coding genes in the GENCODE annotation of the human genome. “

Screen shot 2014-07-03 at 03.50PM, Jul 03With Help From Extinct Humans, Tibetans Adapted To High Altitude – Rae Ellen Bichell – NPR

“According to Nielsen and a bunch of geneticists writing in the journal Nature, the Tibetans appear to have benefited from a genetic gift from the Denisovans, an extinct human ancestor known primarily from a little girl’s tooth and pinkie bone.”

Screen shot 2014-07-03 at 03.49PM, Jul 03NSF to decide all future grant proposals by penalty shoot-out – The Allium

“We feel that this will be a much less random way of giving out funding”, said Dr. France Cordóva, Director of the NSF.”

[hr]

General microbiome and science, June 30

Monday is always a busy day, so lots of papers today. Phages, CRISPRs, antibiotic resistance, probiotics, archaea, biofilms and a Goldilocks planet.

Antibiotics and resistance

Horizontal gene transfer in the human gastrointestinal tract: potential spread of antibiotic resistance genes – JR Huddleston – Infection and Drug Resistance

“This review aims to give an overview of the major horizontal transfer mechanisms and their evolution and then demonstrate the human lower gastrointestinal tract as an environment in which horizontal gene transfer of resistance determinants occurs.”

Screen shot 2014-06-30 at 06.47PM, Jun 30Bacterial persisters: formation, eradication, and experimental systems
Sophie Helaine, Elisabeth Kugelberg – Trends in Microbiology

“Toxin–antitoxin (TA) modules have an important role in the formation of persisters and several studies show that they can form in response to different triggers.”

Screen shot 2014-06-30 at 06.48PM, Jun 30Antibiotic Treatment Suppresses Rotavirus Infection and Enhances Specific Humoral Immunity – Robin Uchiyama – Journal of Infectious Diseases

“Microbiota ablation resulted in reduced rotavirus infection/diarrhea and a more durable rotavirus antibody response, suggesting that antibiotic administration before rotavirus vaccination could raise low seroconversion rates that correlate with the vaccine’s inefficacy in developing regions.”

And:  Antibiotics Help Control Rotavirus Infections and Enhance Antirotaviral Immunity: Are You Serious? – Luther A. Bartelt and Richard L. Guerrant – Journal of Infectious Diseases

“Yes, we must understand intriguing new findings; but no, we are far from serious about widespread use of antimicrobials with routine immunizations.”

Screen shot 2014-06-30 at 06.44PM, Jun 30Transferrin Iron Starvation Therapy for Lethal Bacterial and Fungal Infections – Lin Lin – Journal of Infectious Diseases

“These results provide proof of principle that bacterial infections can be treated in vivo by attacking host targets (ie, trace metal availability) rather than microbial targets.”

Bacterial detection in blood and other sites

Screen shot 2014-06-30 at 06.45PM, Jun 30Identification of pathogens from blood culture bottles in spiked and clinical samples using matrix-assisted laser desorption ionization time-of-flight mass-spectrometry analysis – Simone Konnerth – BMC Research Notes

“MALDI-TOF MS using the SARAMIS database was applied to 37 spiked blood culture samples. Identification rates of spiked samples were as follows: The species level was determined in 16 of 21 (76.2%) Gram negative bacteria and in 11 of 13 (84.6%) Gram positive bacteria. “

Infection and host response

Type I and III Interferon Production in Response to RNA Viruses – Elizabeth Reid and Bryan Charleston – Journal of Interferon & Cytokine Research

“There are now many examples of RNA viruses inducing type I and type III IFNs, and although these IFNs act through different receptors, in many systems studied, they induce a similar spectrum of genes. “

CRISPRs

Screen shot 2014-06-30 at 06.50PM, Jun 30Review: Adapting to new threats: the generation of memory by CRISPR-Cas immune systems – Robert Heler – Molecular Microbiology

“Recent studies have begun to elucidate the genetic requirements for adaptation and have demonstrated that rather than being a stochastic process, the selection of new spacers is influenced by several factors. We review here our current knowledge of the CRISPR adaptation mechanism”

Screen shot 2014-06-30 at 06.53PM, Jun 30The three major types of CRISPR-Cas systems function independently in CRISPR RNA biogenesis in Streptococcus thermophilus – Jason Carte – Molecular Microbiology

“Our findings indicate that multiple CRISPR-Cas systems can function independently in crRNA biogenesis within a given organism – an important consideration in engineering coexisting CRISPR-Cas pathways”

Viruses and phages

Screen shot 2014-06-30 at 06.53PM, Jun 30Exploiting gut bacteriophages for human health – Marion Dalmasso – Trends in Microbiology

“We emphasise the complexity and individuality of the phageome, and the link to the health state of the host. We highlight the practical applications of bacteriophages in medicine and in the food chain.”

Screen shot 2014-06-30 at 06.52PM, Jun 30Environmental bacteriophages : viruses of microbes in aquatic ecosystems – Télesphore Sime – Ngando – Frontiers in Microbiology

“The present chapter sought to review the literature on the diversity and functional roles of viruses of microbes in environmental microbiology, focusing primarily on prokaryotic viruses (i.e. phages) in aquatic ecosystems, which form the bulk of our knowledge in modern environmental viral ecology.”

Archaea

Screen shot 2014-06-30 at 06.55PM, Jun 30Taxonomic database and cut-off value for processing mcrA gene 454 pyrosequencing data by MOTHUR – Sizhong Yang – Journal of Microbiological Methods

“The functional mcrA gene of methanogens can generate phylogeny as congruent as the 16S rRNA gene phylogeny. “

Screen shot 2014-06-30 at 06.59PM, Jun 30Biofilm formation of mucosa-associated methanoarchaeal strains
Corinna Bang – Frontiers in Microbiology

“Here, the ability of three methanoarchaeal strains, Methanobrevibacter smithii and Methanosphaera stadtmanae, which form part of the human gut microbiota, and the Methanosarcina mazei strain Gö1 to grow on different surfaces and form biofilms was investigated.”

Biofilms (see also Archaea above and Probiotics below)

Screen shot 2014-06-30 at 07.02PM, Jun 30Development of an in vitro periodontal biofilm model for assessing antimicrobial and host modulatory effects of bioactive molecules
Emma Millhouse – BMC Oral Health

Multi-species biofilms were either treated with either molecule, or alternatively epithelial cells were treated with these prior to biofilm co-culture. Biofilm composition was evaluated and inflammatory responses quantified at a transcriptional and protein level.

Probiotics

Screen shot 2014-06-30 at 06.43PM, Jun 30Review: Enumeration of probiotic strains: Review of culture-dependent and alternative techniques to quantify viable bacteria – Catherine Davis – Journal of Microbiological Methods

“Consensus on an operational definition of viability and systematic efforts to validate these alternative techniques ultimately will strengthen the accuracy and reliability of probiotic strain enumeration.”

Inhibitory effect of Lactobacillus salivarius on Streptococcus mutans biofilm formation
Chien-Chen Wu – Molecular Oral Microbiology

“We analyzed 64 L. salivarius strains and found that two, K35 and K43, significantly inhibited S. mutans biofilm formation with inhibitory activities more pronounced than those of Lactobacillus rhamnosus GG (LGG), a prototypical probiotic that shows anti-caries activity.

General taxonomy and phylogeny

Screen shot 2014-06-30 at 07.04PM, Jun 30Considering external information to improve the phylogenetic comparison of microbial communities: a new approach based on constrained Double Principal Coordinates Analysis (cDPCoA) – S Dray – Molecular Ecology Resources

“In this work, we extend DPCoA to integrate the information of external variables measured on communities. The constrained Double Principal Coordinates Analysis (cDPCoA) is able to enforce a priori classifications to retrieve subtle differences and(or) remove the effect of confounding factors. “

Screen shot 2014-06-30 at 06.43PM, Jun 30Understanding molecular identification and polyphasic taxonomic approaches for genetic relatedness and phylogenetic relationships of microorganisms – Surajit Das – Journal of Microbiological Methods

“In this regard, a polyphasic taxonomic approach is advantageous because it exploits simultaneously both conventional as well as molecular identification techniques.”

Metabolomics

Screen shot 2014-06-30 at 07.01PM, Jun 30Nutrient sharing in the microbial world – Erica C. Seth and Michiko E. Taga – Frontiers in Microbiology

“Cofactor cross-feeding can contribute to both the health and nutrition of a host organism, the virulence and persistence of pathogens, and the composition and function of environmental communities. “

Metagenomics

Combination of Metagenomics and Culture Based Methods to Study the Interaction Between Ochratoxin A and Gut Microbiota – Mingzhang Guo – Toxicological Sciences

“Changes in functional genes of gut microbiota including signal transduction, carbohydrate transport, transposase, amino acid transport system and mismatch repair were observed.”

Chromosomal organization

NuChart-II: a graph-based approach for the analysis and interpretation of Hi-C data (PDF) – Fabio Tordini – Proceedings of the CIBB 2014

“NuChart-II is a highly optimized implementation of a previous prototype package developed in R, in which the graph-based representation of Hi-C data was tested, but that also showed inevitable problems of scalability while working genome-wide on large datasets.”

Science and education

Screen shot 2014-06-30 at 06.58PM, Jun 30Starting small: using microbiology to foster scientific literacy
Amy F. Savage, Brooke A. Jude – Trends in Microbiology

“In order to achieve scientific literacy for all students, Bard College recently implemented Citizen Science, a common January course for all first-year students. Structured around the question ‘how do we reduce the global burden of disease?’, this course uses microbiological tools to develop an understanding of potential answers.”

 

Dr. Bik’s Picks

Screen Shot 2014-07-01 at 12.06.17 AMBird brains: Public asked to look out for clever rooks – Victoria Gill – BBC News

“The British Trust for Ornithology (BTO) is asking the public to take part in a national survey of bird intelligence. From 1 July, the charity is asking people to submit video clips or descriptions of the behaviour or rooks – some of our cleverest garden birds.”

Screen Shot 2014-07-01 at 12.06.52 AMPotentially habitable Earth-like planet discovered; May have similar temperatures to our planet – Science Daily

“A potentially habitable Earth-like planet that is only 16 light years away has been discovered. The “super-Earth” planet, GJ 832 c, takes 16 days to orbit its red-dwarf star, GJ 832, and has a mass at least five times that of Earth.”

Screen Shot 2014-07-01 at 12.07.35 AMStudy Implicates Smog In Autism And Schizophrenia – Science 2.0

“A recent paper found that exposure to air pollution early in life produces harmful changes in the brains of mice, including an enlargement of part of the brain that is seen in humans who have autism and schizophrenia, and that led them to conclude that smog causes autism.”

[hr]

General microbiology and science, June 27

Viruses in primate genomes, viruses altering shrimp metabolome, transposable elements and repeats, dengue, other infectious diseases in developing countries and Dr. Bik’s Picks.

Metagenomics / viruses

Screen Shot 2014-06-27 at 9.21.29 PMCute animal alert! A tarsier is a tiny primate with huge eyes.
The First Endogenous Herpesvirus, Identified in the Tarsier Genome, and Novel Sequences from Primate Rhadinoviruses and Lymphocryptoviruses – Amr Aswad, Aris Katzourakis – PLOS Genetics

“We describe the first endogenous herpesvirus from the genome of the Philippine tarsier, belonging to the Roseolovirus genus, and characterize its highly defective genome that is integrated and flanked by unambiguous host DNA. From a draft assembly of the aye-aye genome, we use bioinformatic tools to reveal over 100,000 bp of a novel rhadinovirus that is the first lemur gammaherpesvirus, closely related to Kaposi’s sarcoma-associated virus.”

 Metabolomics

Screen Shot 2014-06-27 at 9.32.37 PMAn Invertebrate Warburg Effect: A Shrimp Virus Achieves Successful Replication by Altering the Host Metabolome via the PI3K-Akt-mTOR Pathway – Mei-An Su – PLOS Pathogens

“We show that the PI3K-Akt-mTOR pathway was of central importance in triggering this WSSV-induced Warburg effect. Although dsRNA silencing of the mTORC1 activator Rheb had only a relatively minor impact on WSSV replication, in vivo chemical inhibition of Akt, mTORC1 and mTORC2 suppressed the WSSV-induced Warburg effect and reduced both WSSV gene expression and viral genome replication.”

Biofilms

Screen Shot 2014-06-27 at 9.33.21 PMFilaments in curved streamlines: rapid formation of Staphylococcus aureus biofilm streamers – Minyoung Kevin Kim – New Journal of Physics

“We discovered that S. aureus rapidly forms flow-induced, filamentous biofilm streamers, and furthermore if surfaces are coated with human blood plasma, streamers appear within minutes and clog the channels more rapidly than if the channels are uncoated. “

Chromosomal organization

Screen Shot 2014-06-27 at 9.34.04 PMDigital Genotyping of Macrosatellites and Multicopy Genes Reveals Novel Biological Functions Associated with Copy Number Variation of Large Tandem Repeats – Manisha Brahmachary – PLOS Genetics

“Here, we demonstrate the utility of Nanostring technology as a targeted approach to perform accurate measurement of tandem repeats even at extremely high copy number, and apply this technology to genotype 165 HapMap samples from three different populations and five species of non-human primates. “

Screen Shot 2014-06-27 at 9.34.37 PMLarge-Scale Genomic Analysis Suggests a Neutral Punctuated Dynamics of Transposable Elements in Bacterial Genomes – Jaime Iranzo – PLOS Computational Biology

“In this work, we take advantage of the large amount of genomic data currently available and study the abundance distributions of 33 IS families in 1811 bacterial chromosomes. This allows us to test simple models of IS dynamics and estimate their key parameters by means of a maximum likelihood approach. “

Microbial Ecology

Screen Shot 2014-06-27 at 9.35.00 PMEx Uno Plures: Clonal Reinforcement Drives Evolution of a Simple Microbial Community – Margie Kinnersley – PLOS Genetics

“We previously showed that a population of E. coli that originated from a single clone and was cultured in the presence of a single limiting resource, evolves into a stable, three-membered community, wherein one clone excretes metabolites that the others utilize as carbon sources. To discern the genetic factors at work in producing this outcome and to illuminate the community’s physiology, we sequenced the genomes of the ancestral and evolved clones.”

Infectious diseases in developing countries

Screen Shot 2014-06-27 at 9.35.43 PMExploring the Relationship between Access to Water, Sanitation and Hygiene and Soil-Transmitted Helminth Infection: A Demonstration of Two Recursive Partitioning Tools – Katherine Gass – PLOS Neglected Tropical Diseases

“Improvements to water, sanitation and hygiene (WASH) likely provide sustained benefit, but few rigorous studies have evaluated the specific WASH components most influential in reducing infection. “

Screen Shot 2014-06-27 at 9.36.14 PMSocial Sciences Research on Infectious Diseases of Poverty: Too Little and Too Late? – José Azoh Barry – PLOS Neglected Tropical Diseases

“Besides the vicious circle these diseases maintain with dire conditions of poverty, an increased microbial resistance to some therapeutic drugs adds to the complexity of health disparities and human suffering among the socially disadvantaged, marginalized, and prejudiced against.”

Dengue

Screen Shot 2014-06-27 at 9.36.37 PMVariability in Dengue Titer Estimates from Plaque Reduction Neutralization Tests Poses a Challenge to Epidemiological Studies and Vaccine Development – Henrik Salje – PLOS Neglected Tropical Diseases

“We used repeated assays on the same two pools of serum using five different viruses (2,319 assays) to characterize the variability in the technique under identical experimental conditions. We also assessed the performance of multiple statistical models to interpolate continuous values of neutralization titer from discrete measurements from serial dilutions.”

Science and career

PLOSTen Simple Rules for Approaching a New Job – Philip E. Bourne – PLOS Computational Biology

“Thinking both as a job applicant and a job interviewer about how I have approached job situations over the years before, during, and after the interview and how those situations have turned out, I can offer the following ten simple rules as you prepare.”

A New Online Computational Biology Curriculum – David B. Searls – PLOS Computational Biology

“A recent proliferation of Massive Open Online Courses (MOOCs) and other web-based educational resources has greatly increased the potential for effective self-study in many fields. This article introduces a catalog of several hundred free video courses of potential interest to those wishing to expand their knowledge of bioinformatics and computational biology. “

Arsenic metabolism

Screen Shot 2014-06-27 at 10.00.06 PMAssociations between Arsenic Species in Exfoliated Urothelial Cells and Prevalence of Diabetes among Residents of Chihuahua, Mexico – Jenna M. Currier – Environ Health Perspect

“We measured concentrations of trivalent and pentavalent iAs, methyl-As (MAs), and dimethyl-As (DMAs) species in EUC from 374 residents of Chihuahua, Mexico, who were exposed to iAs in drinking water.”

Dr. Bik’s Picks

Screen Shot 2014-06-27 at 10.09.01 PMWith pictures and videos: Duration of urination does not change with body size – Patricia J. Yang – PNAS

“In this study, we report a mathematical model that clarifies misconceptions in urology and unifies the results from 41 independent urological and anatomical studies. The theoretical framework presented may be extended to study fluid ejection from animals, a universal phenomenon that has received little attention.”

Screen Shot 2014-06-27 at 10.01.44 PMFrom Gemstones to Arsenic: How the Development of Pigment Colored Art – Allison Meier

“A new exhibition at London’s National Gallery — Making Colour — looks at the development of color in art, from the Middle Ages to 1900. “

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Human microbiome, June 26

Mass spectrometry on Neanderthal poop – how cool is that? Then, nice article about fecal transplants, the Bristol Stool Chart Mug, role of bacteria in colon cancer, and Mycobacterium tuberculosis as a possible human symbiont.

Gut microbiome

Screen Shot 2014-06-26 at 10.22.55 PMThe Neanderthal Meal: A New Perspective Using Faecal Biomarkers – Ainara Sistiaga – PLOS ONE

“Our gas chromatography-mass spectrometry results from El Salt (Spain), a Middle Palaeolithic site dating to ca. 50,000 yr. BP, represents the oldest positive identification of human faecal matter.”

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I enjoyed reading this article. And not just because they mentioned one of our studies.
Getting to the Bottom of Fecal Transplants – Ricki Lewis – PLOS.org

“(…) babies’ bacteria were quite different at the outset, but by the end of the year, their communities resembled those in the adult digestive tract. And it was published right here at PLOS.”

41C8qjeUK2LWhich led me to the awesome The Bristol Stool Chart Mug – Amazon
Which I then ordered.

 

CRCFusobacterium and Enterobacteriaceae: Important players for CRC? – Emma Allen-Vercoea, Christian Jobin – Immunology Letters

“Not surprisingly, microbial dysbiosis is associated with numerous intestinal disorders including inflammatory bowel diseases (IBD) and colorectal cancer (CRC). In this piece, we will review recent evidence that gut microbial dysbiosis can influence intestinal disease, including colitis and CRC.”

Screen Shot 2014-06-26 at 9.45.42 PMPrevalence and Duration of Asymptomatic Clostridium difficile Carriage among Healthy Subjects in Pittsburgh, Pennsylvania – Alison L. Galdys – Journal of Clinical Microbiology

“The prevalence of C. difficile carriage in this healthy cohort is concordant with prior estimates. C. difficile-colonized individuals may be important reservoirs for C. difficile and may falsely test positive for infections due to C. difficile when evaluated for community-acquired diarrhea caused by other enteric pathogens.”

Blood sugar improves with first gastrointestinal microbiome modulator, NM504 – Science Daily

“The not-yet-named therapeutic, NM504, is the first in a new class of therapies known as GI microbiome modulators. “

Role of humanRole of human gut microbiota metabolism in the anti-inflammatory effect of traditionally used ellagitannin-rich plant materials – Jakub P. Piwowarski – Journal of Ethnopharmacology

“The formation of urolithins was determined by ex vivo incubation of human faecal samples with aqueous extracts from selected plant materials.”

Me and my microbiome – New Scientist

“Now there are claims that a truly villainous bacterium – Mycobacterium tuberculosis, which causes TB – is actually symbiotic and helped us evolve our large brains (see “ Eat meat TB brainy”). “

Eat meat TB brainy – Adrian Williams, Robin Dunbar – New Scientist

“The tuberculosis bacterium co-evolved with humans at least 70,000 years ago, and possibly a great deal earlier. Could chronic TB infections have originally been beneficial to human life? Did the pathogen act as a symbiont, supplying nicotinamide at times of meat deficiency?”

Animal models of human microbiota and disease

Screen Shot 2014-06-26 at 9.47.30 PMIncorporation of therapeutically modified bacteria into gut microbiota inhibits obesity – Zhongyi Chen – Journal of Clinical Investigation

“Here, we demonstrated that administration of engineered NAPE-expressing E. coli Nissle 1917 bacteria in drinking water for 8 weeks reduced the levels of obesity in mice fed a high-fat diet. “

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General microbiology and science, June 25

Arsenic profiling in rats, Bacillus in space, and antibiotic resistance in populations. And Dr. Bik’s Picks featuring butterflies, mummies and unfeelability cloaks.

Microbes in space

Screen Shot 2014-06-25 at 10.31.28 PMBacillus anthracis-Like Bacteria and Other B. cereus Group Members in a Microbial Community Within the International Space Station: A Challenge for Rapid and Easy Molecular Detection of Virulent B. anthracis – Sandra P. van Tongeren – PLOS ONE

“In this study we show the presence of B. anthracis-like bacteria and other members of the B. cereus group in a microbial community within the human environment of the International Space Station and their preliminary identification by using conventional culturing as well as molecular techniques including 16S rDNA sequencing, PCR and real-time PCR. “

Metagenomics

Screen Shot 2014-06-25 at 10.31.54 PMElucidation of Operon Structures across Closely Related Bacterial Genomes – Chuan Zhou – PLOS ONE

“Here we developed a graph-based model to elucidate the diversity of operon structures across a set of closely related bacterial genomes.”

Antibiotic resistance

Screen Shot 2014-06-25 at 10.32.23 PMOptimization of lag time underlies antibiotic tolerance in evolved bacterial populations – Ofer Fridman – Nature

“Here we followed the evolution of bacterial populations under intermittent exposure to the high concentrations of antibiotics used in the clinic and characterized the evolved strains in terms of both resistance and tolerance. “

Arsenic metabolism

Screen Shot 2014-06-25 at 10.32.54 PMThe metabolomic profiling of serum in rats exposed to arsenic using UPLC/Q-TOF MS – Cheng Wang – Toxicology Letters

“The aim of this study is to determine the impact of chronic arsenic exposure on the metabolism of organism, and find the metabolites changes by using metabolomic techniques. “

Screen Shot 2014-06-25 at 10.33.15 PMInvestigation of arsenic species stability by HPLC-ICP-MS in plants stored under different conditions for 12 months – Clarice D.B. Amaral – Microchemical Journal

“For the As species here studied it can be concluded that lyophilization and cryogenic grinding strategies were the most suitable sample pretreatments for As speciation in plant tissue.”

Science and careers

Screen Shot 2014-06-25 at 10.33.54 PMLove in the lab: Close collaborators – Kerri Smith – Nature

“Romance often sparks between colleagues, and scientists are no different. Nature profiles four super-couples who have combined love and the lab.”

Dr. Bik’s Picks

Screen Shot 2014-06-25 at 10.35.06 PMMetagenomic Analysis Reveals Presence of Treponema denticola in a Tissue Biopsy of the Iceman – Frank Maixner – PLOS ONE

“Initially, the metagenomic data of the Iceman’s genomic survey was screened for bacterial ribosomal RNA (rRNA) specific reads. Through ranking the reads by abundance a relatively high number of rRNA reads most similar to T. denticola was detected. “

Screen Shot 2014-06-25 at 10.35.42 PMA magnetic compass aids monarch butterfly migration – Patrick A Guerra – Nature Communications

“Here we use flight simulator studies to show that migrants indeed possess an inclination magnetic compass to help direct their flight equatorward in the fall. “

Screen Shot 2014-06-25 at 10.36.07 PMAn elasto-mechanical unfeelability cloak made of pentamode metamaterials
T. Bückmann – Nature Communications

“Here, inspired by invisible core-shell nanoparticles in optics, we design an approximate elasto-mechanical core-shell ‘unfeelability’ cloak based on pentamode metamaterials. “

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General microbiology and science, June 24

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

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

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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