Monthly Archives: July 2014

Human microbiome, July 17

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Protozoa detection in fecal samples from children, airway microbiome, and Staphylococcus transmission between mother and child.

Oral microbiome

Oral Lihong GuoIntercellular communications in multispecies oral microbial communities – Lihong Guo – Frontiers in Microbiology

“This review will summarize the evidence that oral microbes participate in intercellular communications with co-inhabitants through cell contact-dependent physical interactions, metabolic interdependencies, as well as coordinative signaling systems to establish and maintain balanced microbial communities.”

Respiratory microbiome

Screen Shot 2014-07-17 at 4.58.37 PMAirway Microbiome Dynamics in Exacerbations of Chronic Obstructive Pulmonary Disease – Yvonne J. Huang – Journal of Clinical Microbiology

“In this study, temporal changes in the airway microbiome before, at the onset of, and after an acute exacerbation were examined in 60 sputum samples collected from subjects enrolled in a longitudinal study of bacterial infection in COPD.”

Screen Shot 2014-07-17 at 4.59.26 PMTime between Collection and Storage Significantly Influences Bacterial Sequence Composition in Sputum Samples from Cystic Fibrosis Respiratory Infections – Leah Cuthbertson – Journal of Clinical Microbiology

“Samples were treated with propidium monoazide to distinguish live from dead cells prior to DNA extraction, and 16S rRNA gene pyrosequencing was used to characterize their bacterial compositions.”

Gut microbiome

Screen Shot 2014-07-17 at 4.58.09 PMThe devil lies in the details: How variations in polysaccharide fine-structure impact the physiology and evolution of gut microbes – Eric C. Martens – Journal of Molecular Biology

“Here, we review the recent literature on this topic and posit that numerous, subtle variations in polysaccharides diversify the spectrum of available nutrient niches, each of which may be best filled by a subset of microorganisms that possess the corresponding proteins to recognize and degrade different carbohydrates”

Pregnancy and birth

Protozoa pediatricDetection of intestinal protozoa in paediatric patients with gastrointestinal symptoms by multiplex real-time PCR – L. Maas – Clinical Microbiology and Infection

“The performance of a multiplex real-time PCR for the detection of Blastocystis, Dientamoeba fragilis, Giardia lamblia, Cryptosporidium species and Entamoeba species in faecal samples was evaluated in an observational prospective study.”

Staph transmTransmission of Staphylococcus aureus between mothers and infants in an African setting – F. Schaumburg – Clinical Microbiology and Infection

“We aimed to investigate the transmission of S. aureus between mothers and their newborns during the first year after delivery in an African setting. In a longitudinal cohort study, colonization of Gabonese mother–infant pairs was assessed at delivery and after 1, 9 and 12 months.”

Commentary: Travelling within the fetal gut: simple rules for an arduous journey
Qiling Xu – BMC Microbiology

“A recent paper in BMC Biology addresses this issue with live imaging of gut explants from mouse embryos.”

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General microbiology and science, July 16

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Comparison of 1700 metagenomes,  $125,000 to study 100 trillion bacteria, arsenic speciation, and the Seinfeld “double dipping” videoclip.

General microbiome and metagenome

Metagenome exploringExploring Neighborhoods in the Metagenome Universe – Kathrin P. Aßhauer – International Journal of Molecular Sciences

“Our evaluation on more than 1700 publicly available metagenomes indicates that for a query metagenome from a particular habitat on average nine out of ten nearest neighbors represent the same habitat category independent of the utilized profiling method or distance measure. “

UMass Cancer Avatar Institute, Center for Microbiome Research backed by UMass president

“Beth McCormick, PhD, professor of microbiology & physiological systems, was also awarded $125,000 to develop the Center for Microbiome Research, envisioned as a center of research and education for the microbiome, the ecosystem of the 100 trillion bacteria in the human body.”

Dengue virus

Endothelial Cells in Dengue Hemorrhagic Fever – Anon Srikiatkhachorn – Antiviral Research

“In this review we summarize dengue viruses and the spectrum of human disease and highlight evidence of endothelial cell dysfunction in DHF based on studies in patients and mouse and tissue culture models. “

Dengue fever and bone marrow myelofibrosis – Xin Qing – Experimental and Molecular Pathology

“We report the first case to our knowledge of myelofibrosis associated with dengue fever. We briefly describe dengue infections and hypothesize the causes of myelofibrosis in this condition.”

African genetic ancestry is associated with a protective effect on Dengue severity in colombian populations – Juan C. Chacón-Duque – Infection, Genetics and Evolution

“We found that African ancestry has a protective effect against severe outcomes under several systems of clinical classification”

Conference abstract: Longitudinal Analysis Of Dengue Fever Infections Reported In The Uk Betwen 2002 – 2013 Using The Health Improvement Network (Thin) Primary Care Database – D Ansell – Value in Health

Polio virus

Comment: Infectious disease: Polio eradication hinges on child health in Pakistan – Zulfiqar Ahmed Bhutta – Nature

“Last year, only 406 cases were reported, with 160 of them in just a few areas of the three countries where polio remains endemic”

Microbes in the news

Gut feeling: How intestinal bacteria may influence our moods – Sharon Oosthoek – CBC News

“Dr. Emeran Mayer, a gastroenterologist at University of California, Los Angeles, is a self-described sceptic, but admits “there is enough there to make me think some of the findings from animal studies can be extrapolated to humans.””

#BacteriaHysteria: Double-dipping spreads bacteria. But does it get people sick? (with the famous Seinfeld clip) – Joseph Stromberg – Vox.com

“Many people believe that dipping a chip into a shared bowl of drip, taking a bite, and dipping again — termed “double-dipping” in a 1993 episode of Seinfeld — is an abhorrently unsanitary practice. Others, like George Costanza, think this aversion is unscientific, and there’s actually no harm in double-dipping at all.”

Sizing up bacteria – Peter Reuell – Harvard Gazette

“A new theoretical framework outlined by a Harvard scientist could help solve the mystery of how bacterial cells coordinate processes that are critical to cellular division, such as DNA replication, and how bacteria know when to divide.”

Chilling new details on cold-storage smallpox – Hoai-Tran Bui and Alison Young, USA TODAY

Arsenic metabolism

arsenicComplementary Arsenic Speciation Methods: A Review – Michelle M. Nearing – Spectrochimica Acta Part B: Atomic Spectroscopy

“The toxicity of arsenic greatly depends on its chemical form and oxidation state (speciation) and therefore accurate determination of arsenic speciation is a crucial step in understanding its chemistry and potential risk.”

Science, ethics and publishing

Should Research Fraud be a Crime? A Reader Poll – Ed Silverman – Wall Street Journal

“A researcher may lose a job or stature, but should there be more serious consequences, such as criminal liability? A debate between two academics in BMJ, the British Medical Journal, explores the yin and yang surrounding this question.“

Dr. Bik’s Picks

Great title! IgG walkingIgGs are made for walking on bacterial and viral surfaces – Johannes Preiner – Nature Communications

“Here we utilize high-speed atomic force microscopy to examine the dynamics of antibody recognition and uncover a principle; antibodies do not remain stationary on surfaces of regularly spaced epitopes; they rather exhibit ‘bipedal’ stochastic walking”

Human (and fish) microbiome, July 16

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Oral microbiome in children with leukemia, and effects of antibiotics on fish microbiota.

Human oral microbiome

Oral Microbiota Distinguishes Acute Lymphoblastic Leukemia Pediatric Hosts from Healthy Populations – Yan Wang – PLOS ONE

“The oral microbiota of leukemia patients had lower richness and less diversity compared to healthy controls.”

Human gut microbiome

Editorial: New bacteria associated with diarrhoea – Cláudio Nunes-Alves – Nature Reviews Microbiology

“Pop et al. used high throughput 16S rRNA sequencing to compare the faecal microbiota composition in 992 children from Gambia, Mali, Kenya and Bangladesh”

Pregnancy and birth

Yes, this one is not really microbiome-related, but it touched my heart:

Screen Shot 2014-07-16 at 11.49.15 PMStrangers help with photo in midst of tragedy – Dorrine Mendoza, CNN

“”My daughter recently passed away after a long battle in the children’s hospital. She was in the hospital her whole life and we were never able to get a photo without all her tubes. Can someone remove the tubes?””

Fish microbiome

Effects of antibiotic on the bacterial microflora in two commercially
important catfish species, Clarias batrachus and Heteropneustes fossilis in
Bangladesh – Md. Shahdat Hossain – Journal of Coastal Life Medicine

“During the experiment, bacterial loads were estimated as colony forming unit (CFU/g) by every alternate day in the aquarium water, gills, skin and intestine of fish.”

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General microbiology and science, July 15

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Dengue virus replication, poliovirus transmission, marine viral communities, primer choice, and CRISPRs systems and antibiotic resistance.

Dengue virus

Letter: Are viral small RNA regulating Dengue virus replication beyond serotype 2? – Esteban Finol – PNAS

Letter: Reply to Finol: Viral small RNA from Dengue virus and its egulatory role in different serotypes – Mazhar Hussain and Sassan Asgari – PNAS

Poliovirus

Screen shot 2014-07-15 at 06.00PM, Jul 15The role of older children and adults in wild poliovirus transmission – Isobel M. Blake – PNAS

“We fit a mathematical model of poliovirus transmission to time series data from two large outbreaks that affected adults (Tajikistan 2010, Republic of Congo 2010) using maximum-likelihood estimation based on iterated particle-filtering methods. “

Phages and viruses

Screen shot 2014-07-15 at 06.01PM, Jul 15Modeling ecological drivers in marine viral communities using comparative metagenomics and network analyses – Bonnie L. Hurwitz – PNAS

“Here we combine advances in bioinformatics (shared k-mer analyses) and social networking (regression modeling) to develop an annotation- and assembly-free visualization and analytical strategy for comparative metagenomics that uses all the data in a unified statistical framework. “

Screen shot 2014-07-15 at 06.02PM, Jul 15Contrasted coevolutionary dynamics between a bacterial pathogen and its bacteriophages – Alex Betts – PNAS

“We used experimental evolution between Pseudomonas aeruginosa and a panel of its lytic phages and found the full known range of coevolutionary dynamics.”

CRISPRs and antibiotic resistance

Screen shot 2014-07-15 at 06.03PM, Jul 15A CRISPR-Cas system enhances envelope integrity mediating antibiotic resistance and inflammasome evasion – Timothy R. Sampson – PNAS

“We demonstrate that components of a clustered, regularly interspaced, short palindromic repeats–CRISPR associated (CRISPR-Cas) system, a prokaryotic defense against viruses and foreign nucleic acid, act to regulate the permeability of the bacterial envelope, ultimately providing these cells with the capability to resist membrane damage caused by antibiotics. “

Extraction and amplification techniques

The Influence of DNA Extraction Procedure and Primer Set on the Bacterial Community Analysis by Pyrosequencing of Barcoded 16S rRNA Gene Amplicons – Ingo C. Starke – Molecular Biology International

“In this study, the effect of different DNA extraction procedures and primer sets on pyrosequencing results regarding the composition of bacterial communities in the ileum of piglets was investigated. “

Metagenomics general

Interpreting 16S metagenomic data without clustering to achieve sub-OTU resolution – Mikhail Tikhonov – ISME Journal

“We present a clustering-free approach to multi-sample Illumina data sets that can identify independent bacterial subpopulations regardless of the similarity of their 16S tag sequences. “

 

General Microbiology

Screen shot 2014-07-15 at 06.04PM, Jul 15Recovery of a Medieval Brucella melitensis Genome Using Shotgun Metagenomics – Gemma L. Kay – mBio

“We sequenced the metagenome of a calcified nodule from the skeleton of a 14th-century middle-aged male excavated from the medieval Sardinian settlement of Geridu. We obtained 6.5-fold coverage of a Brucella melitensis genome”

Screen shot 2014-07-15 at 06.05PM, Jul 15Review: The Ins and Outs of Bacterial Iron Metabolism – Elaine R. Frawley and Ferric C. Fang – Molecular Microbiology

“The recent discovery of putative iron efflux transporters in Salmonella enterica serovar Typhimurium is discussed in the context of cellular iron homeostasis.”

Screen shot 2014-07-15 at 06.05PM, Jul 15 1Genetic information transfer promotes cooperation in bacteria – Tatiana Dimitriu – PNAS

“Our experiments and models converge to show that when both cheating and cooperative genes are transferred, cooperators win against cheaters because transfer increases assortment among alleles, favoring cooperation.”

Challenges and Opportunities of Integrative Taxonomy for Research and Society – Taxonomic Research in the Era of OMICS Technologies (PDF)  (Herausforderungen und Chancen der integrativen Taxonomie für Forschung und Gesellschaft) – Deutsche Akademie der Naturforscher Leopoldina e.V.

Microbiomes and metagenomes in need of professional classification – Rudolf Amann
The intestinal microbiome and human health: a new challenge for taxonomy of metagenomic data – Bärbel Stecher
Characterizing species boundaries and species histories in closely related fungi using comparative population genomic approaches – Eva H. Stukenbrock

Coming of ageThe coming of age of microbial ecology – Ana E. Escalante and Silvia Pajares – Chapter in Open Access book: Frontiers in Ecology, Evolution and Complexity

“Despite major challenges, new technological advances in genomic sciences have prompted microbial ecology into a revolution in data generation that has allowed us to move beyond studies of single isolates to the study of entire microbial communities without reliance on culture-dependent methods.”

Review: The Dynamic Interactions between Salmonella and the Microbiota, within the Challenging Niche of the Gastrointestinal Tract – C. M. Anjam Khan – International Scholarly Research Notices

“This gastrointestinal pathogen not only faces the hostile defenses of the host’s immune system, but also faces fierce competition from the large and diverse community of microbiota for space and nutrients.”

 

Science and publishing

Screen shot 2014-07-15 at 05.59PM, Jul 15Is Social Media Saving Science? – Michael White – Pacific Standard

“Why do editors and expert reviewers, whose primary job is to vet manuscripts, miss major flaws that are so obvious to readers after the papers are published?”

Dr. Bik’s Picks

Screen shot 2014-07-15 at 06.07PM, Jul 15Effect of sleep deprivation on the human metabolome – Sarah K. Davies – PNAS

“Clear daily rhythms were observed in most metabolites, with 24 h wakefulness mainly reducing the amplitude of these rhythms.”

Screen shot 2014-07-15 at 06.06PM, Jul 15Comparison of five different RNA sources to examine the lactating bovine mammary gland transcriptome using RNA-Sequencing – Angela Cánovas – Nature Scientific Reports

“Our results provide a comparison between different sampling methods (invasive and non-invasive) to define the transcriptome of mammary gland tissue and milk cells.’

Screen shot 2014-07-15 at 06.07PM, Jul 15 1Superior time perception for lower musical pitch explains why bass-ranged instruments lay down musical rhythms – Michael J. Hove – PNAS

“Here, we show that, when two streams of tones are presented simultaneously, the brain better detects timing deviations in the lower-pitched than in the higher-pitched stream and that tapping synchronization to the tones is more influenced by the lower-pitched stream. “

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Non-human microbiome, July 15

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Murine skin commensals, nematodes, Bordeaux vines, polar soil, and water.

Mice microbiome

Adaptive immunity to murine skin commensals – Wei Shen – PNAS

“Here we report, for the first time, that commensal skin bacteria are recognized by major populations of T cells in skin-draining lymph nodes of mice.”

Nematode microbiome

Screen shot 2014-07-15 at 05.21PM, Jul 15NilD CRISPR RNA contributes to Xenorhabdus nematophila colonization of symbiotic host nematodes – Jeff L. Veesenmeyer – Molecular Microbiology

“Our data demonstrate that NilD RNA is conditionally necessary for mutualistic host colonization and suggest that it functions to regulate endogenous gene expression.”

Plant microbiome

Screen shot 2014-07-15 at 05.37PM, Jul 15Characterization of Pythium oligandrum populations that colonise the rhizosphere of vines from the Bordeaux region – Jonathan Gerbore – FEMS Microbiology Ecology

“The present study focused on one oomycete, Pythium oligandrum, well-known for its plant protection abilities, which thrives in microbial environment where bacteria and fungal communities are also present. “

Environmental microbial communities  (also see Human Gut digest)

Screen shot 2014-07-15 at 05.18PM, Jul 15Conditionally Rare Taxa Disproportionately Contribute to Temporal Changes in Microbial Diversity – Ashley Shade – mBio

“Using 16S rRNA amplicon sequencing of 3,237 samples from 42 time series of microbial communities from nine different ecosystems (air; marine; lake; stream; adult human skin, tongue, and gut; infant gut; and brewery wastewater treatment), we introduce a new method to detect typically rare microbial taxa that occasionally become very abundant (conditionally rare taxa [CRT]) and then quantify their contributions to temporal shifts in community structure.”

Soil microbiome

Screen shot 2014-07-15 at 05.38PM, Jul 15Environmental drivers of soil microbial community distribution at the Koiliaris Critical Zone Observatory – Myrto Tsiknia – FEMS Microbiology Ecology

“This study investigates the distribution of archaea, bacteria and fungi as well as the dominant bacterial phyla (Acidobacteria, Actinobacteria, Bacteroidetes, Firmicutes), and classes of Proteobacteria (α- and β-Proteobacteria) across the Koiliaris watershed by qPCR and associate them with environmental variables. “

SicilianoSoil fertility is associated with fungal and bacterial richness, whereas pH is associated with community composition in polar soil microbial communities – Steven D. Siciliano – Soil Biology and Biochemistry

“We quantified richness, evenness and taxonomic composition of both fungi and bacteria in 223 Arctic and Antarctic soil samples across 8 locations to test the global applicability of hypotheses concerning edaphic drivers of soil microbial communities that have been primarily developed from studies of bacteria in temperate and tropical systems.”

TianThe effect of irrigation with oil-polluted water on microbial communities in estuarine reed rhizosphere soils – Weijun Tian – Ecological Engineering

“PCR-denaturing gradient gel electrophoresis profiles revealed that the structure of the bacterial community was generally less affected, but the dominant flora was changed.”

Metatranscriptomic analysis of Arctic peat soil microbiota – Alexander Tveit – Applied and Environmental Microbiology

“A comparative analysis of mRNA enriched and non-enriched metatranscriptomes showed that mRNA enrichment resulted in a two-fold increase in the relative abundance of mRNA, but biased the relative distribution of mRNA. “

Screen shot 2014-07-15 at 07.15PM, Jul 15Network analysis reveals that bacteria and fungi form modules that correlate independently with soil parameters – Alexandre B de Menezes – Environmental Microbiology

“Network and multivariate statistical analyses were performed to determine interactions between bacterial and fungal community T-RFLPs as well as soil properties in paired woodland and pasture sites.”

Screen shot 2014-07-15 at 07.12PM, Jul 15 1Dynamic Succession of Soil Bacterial Community during Continuous Cropping of Peanut (Arachis hypogaea L.) – Mingna Chen – PLOS ONE

“In this study, 16S rRNA gene clone library analyses were used to study the succession of soil bacterial communities under continuous peanut cultivation.”

Diversity of Bacterial Communities in a Profile of a Winter Wheat Field: Known and Unknown Members – Aurore Stroobants – Microbial Ecology

“In the present work, we have used bar-coded pyrosequencing analysis of the V3 region of the 16S rRNA gene to analyze bacterial diversity in a profile (depths 10, 25, and 45 cm) of a well-characterized field of winter wheat.”

Expression of copper-resistance genes in microbial communities under copper stress and oxic/anoxic conditions – Ludovic Besaury – Environmental Science and Pollution Research

“The abundance and expression of the copper-resistance genes cusA and copA, encoding respectively for a Resistance Cell Nodulation protein and for a P-type ATP-ase pump, was assessed along a gradient of copper concentration in microcosms prepared from Seine estuary mudflat sediment. “

Water microbiome

Screen shot 2014-07-15 at 05.40PM, Jul 15Distinct bacterial assemblages reside at different depths in Arctic multiyear sea ice – Ido Hatam – FEMS Microbiology Ecology

“Here, we determine whether bacterial communities: 1) differ with ice depth due to strong physical and chemical gradients, 2) are relatively homogenous within a layer, but differ between layers, or 3) do not vary with ice depth”

Screen shot 2014-07-15 at 05.41PM, Jul 15Microspatial gene expression patterns in the Amazon River Plume – Brandon M. Satinsky – PNAS

“The bacterial and archaeal communities associated with a phytoplankton bloom in Amazon River Plume waters at the outer continental shelf in June 2010 harbored ∼1.0 × 1013 genes and 4.7 × 1011 transcripts per liter that mapped to several thousand microbial genomes.”

Screen shot 2014-07-15 at 05.42PM, Jul 15Synchronous dynamics and correlations between bacteria and phytoplankton in a subtropical drinking water reservoir – Lemian Liu – FEMS Microbiology Ecology

“In this study, we evaluated the correlations between bacteria and phytoplankton communities, and determined the relative contribution of phytoplankton community succession to temporal variation of BCC in a subtropical drinking water reservoir (Tingxi Reservoir, southeast China).”

Screen shot 2014-07-15 at 07.12PM, Jul 15Metabolic and phylogenetic profile of bacterial community in Guishan coastal water (Pearl River Estuary), South China Sea – Xiaojuan Hu – Journal of Ocean University of China

“In the present study, the metabolic and phylogenetic profile of the bacterioplankton community in Guishan coastal water (Pearl River Estuary), South China Sea, at 12 sites (S1-S12) were explored by community-level physiological profiling (CLPP) with BIOLOG Eco-plate and denaturing gradient gel electrophoresis (DGGE).”

 

Bioreactor microbiomes

Screen shot 2014-07-15 at 05.39PM, Jul 15

Shifts in the Microbial Community, Nitrifiers and Denitrifiers in the Biofilm in a Full-scale Rotating Biological Contactor – Xingxing Peng – Environmental Science & Technology

“The microbial consortia were profiled using multiple approaches, including 454 high-throughput sequencing of the V3–V4 region of 16S rRNA gene, clone libraries, and quantitative polymerase chain reaction (qPCR). “

Enzymatic characterizationEnzymatic characterization of microbial isolates from lignocellulose waste composting: Chronological evolution – Juan Antonio López-González – Journal of Environmental Management

“Ammonification (72.04%), amylolysis (35.65%), hemicellulolyis (30.75%), and proteolysis (33.61%) were the more frequent activities among isolates, with mesophilic bacteria and fungi as the prevalent microbial communities.”

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Human microbiome, July 15

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Not-always-rare taxa in a wide range of ecosystems, microbiome in early life, focus on Lactobacillus and Bacteroides and microbiota and inflammation.

General microbiome

Science Webinar: The promise of the microbiome: Function and dysfunction in humans and beyond – David A. Relman, Jack A. Gilbert, Rob Knight

“Microbiomes–the distinct microbial populations that colonize an array of bodily and environmental niches–are rapidly gaining prominence in numerous fields of research. “

Gut microbiome

Screen shot 2014-07-15 at 05.18PM, Jul 15Conditionally Rare Taxa Disproportionately Contribute to Temporal Changes in Microbial Diversity – Ashley Shade – mBio

“Using 16S rRNA amplicon sequencing of 3,237 samples from 42 time series of microbial communities from nine different ecosystems (air; marine; lake; stream; adult human skin, tongue, and gut; infant gut; and brewery wastewater treatment), we introduce a new method to detect typically rare microbial taxa that occasionally become very abundant (conditionally rare taxa [CRT]) and then quantify their contributions to temporal shifts in community structure.”

Screen shot 2014-07-15 at 05.20PM, Jul 15Functional genomics of Lactobacillus casei establishment in the gut – Hélène Licandro-Seraut – PNAS

“By determining the relative quantity of each of the 1,110 mutants before and after the in vivo challenge, we identified a core of 47 L. casei genes necessary for its establishment in the gut. “

Screen shot 2014-07-15 at 05.21PM, Jul 15Tuning transcription of nutrient utilization genes to catabolic rate promotes growth in a gut bacterium – Varsha Raghavan – Molecular Microbiology

“We report that the regulator controlling utilization of chondroitin sulfate (CS) in the mammalian gut symbiont Bacteroides thetaiotaomicron is activated by an intermediate in CS breakdown rather than CS itself.”

Pregnancy and Birth

Screen shot 2014-07-15 at 06.38PM, Jul 15 1Review: The Microbiome in Early Life: Self-Completion and Microbiota Protection as Health Priorities – Rodney R. Dietert – Birth Defects Research Part B: Developmental and Reproductive Toxicology

“This minireview considers the benefits of refocusing attention away from treating the patient as a mammalian human to managing the complete patient: a majority microbial superorganism. “

Screen shot 2014-07-15 at 06.38PM, Jul 15Review: Anaerobes and Bacterial Vaginosis in Pregnancy: Virulence Factors Contributing to Vaginal Colonisation – Charlene W. J. Africa – Int. J. Environ. Res. Public Health

“This paper reviewed new available information regarding possible factors contributing to the establishment of the BV vaginal biofilm, examined the proposed role of anaerobic microbial species recently detected by new culture-independent methods and discusses developments related to the effects of BV on human pregnancy. “

Oral microbiome

Review: Acquisition and maturation of oral microbiome throughout childhood: An update – Benedita Sampaio-Maia – Dental Research Journal

“This revision presents an overview of this renewed knowledge on oral microbial community acquisition in the newborn and on the evolution of this microbiome to adulthood. “

 

Animal models of human microbiome and disease

Screen shot 2014-07-15 at 05.17PM, Jul 15Commensal microbes drive intestinal inflammation by IL-17–producing CD4+ T cells through ICOSL and OX40L costimulation in the absence of B7-1 and B7-2 – Lijun Xin – PNAS

“Here we show that B7 deprivation in mice overrides the necessity for Tregs in averting systemic autoimmunity and inflammation in extraintestinal tissues, whereas peripherally induced Tregs retained in the absence of B7 selectively mitigate intestinal inflammation caused by Th17 effector CD4+ T cells. “

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General microbiology and science, July 14

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Rectal swabs instead of stool samples, faster way of finding orthologs, and intelligence in bacteria.

Bioinformatics

Screen shot 2014-07-14 at 06.24PM, Jul 14Quickly Finding Orthologs as Reciprocal Best Hits with BLAT, LAST, and UBLAST: How Much Do We Miss? – Natalie Ward, Gabriel Moreno-Hagelsieb – PLOS ONE

“Since sequence comparison can be time consuming, we decided to compare the number and quality of RBHs detected using algorithms that run in a fraction of the time as BLAST. We tested BLAT, LAST and UBLAST.”

Sampling techniques

Screen shot 2014-07-14 at 06.24PM, Jul 14ectal Swabs for Analysis of the Intestinal Microbiota – Andries E. Budding – PLOS ONE

“In this study we investigated the characteristics and applicability of rectal swabs for gut microbiota profiling in a clinical routine setting in patients presenting with various gastro-intestinal disorders. We found that rectal swabs appeared to be a convenient means of sampling the human gut microbiota.”

Screen shot 2014-07-14 at 06.25PM, Jul 14Some Are More Equal – A Comparative Study on Swab Uptake and Release of Bacterial Suspensions – Philipp Warnke – PLOS ONE

“Highest amount of CFU release was detected for the MWE Dryswab in the unrestricted setting for both S. aureus and S. epidermidis with 1544 CFU and 553 CFU, respectively, lowest release for the Sarstedt neutral swab with 32 CFU and 17 CFU, respectively (p<0.001).”

Antibiotics, resistance, biofilms

Screen shot 2014-07-14 at 06.26PM, Jul 14Beta-Lactam Antibiotics Stimulate Biofilm Formation in Non-Typeable Haemophilus influenzae by Up-Regulating Carbohydrate Metabolism – Siva Wu – PLOS ONE

“When exposed to sub-inhibitory concentrations of beta-lactam antibiotics NTHi strains produced tightly packed biofilms with decreased numbers of culturable bacteria but increased biomass.”

General microbiology

Screen shot 2014-07-14 at 12.23PM, Jul 14Macromolecular networks and intelligence in microorganisms – Hans V. Westerhoff – Frontiers in Microbiology

“Here, we explore how macromolecular networks in microbes confer intelligent characteristics, such as memory, anticipation, adaptation and reflection and we review current understanding of how network organization reflects the type of intelligence required for the environments in which they were selected.”

Screen shot 2014-07-14 at 06.26PM, Jul 14 1The syndemics of childhood diarrhoea: A biosocial perspective on efforts to combat global inequities in diarrhoea-related morbidity and mortality – Nicola Bulled – Global Public Health

“Drawing from available literature, this paper uses syndemic theory to explore the role of adverse biosocial interactions in increasing the total disease burden of enteric infections in low-resources populations and assesses the limitations of recent global calls to action.”

Bacteria in the news

Screen shot 2014-07-14 at 06.19PM, Jul 14We Are Our Bacteria – Jane E. Brody – New York Times (illustration by Ken Orvidas)

“We may think of ourselves as just human, but we’re really a mass of microorganisms housed in a human shell.”

Screen shot 2014-07-14 at 06.27PM, Jul 14#BacteriaHysteria : Gross! Lots of bacteria found on new swimsuits – Jane Weaver – Today Health

“The removable liner in women’s swimsuits that is meant to protect the fabric from our cooties isn’t really protective after all, according to a microbe researcher. “

Screen shot 2014-07-14 at 06.28PM, Jul 14Milford hospital enlists robots in war against infections – Mary MacDonald – Boston Globe

“The robots, made by Xenex Disinfection Services, use an intense flash of ultraviolet light to fight the bacteria, viruses, fungi, and other micro-organisms that traditional cleaning methods can miss, according to the hospital’s infection control staff.”

Screen shot 2014-07-14 at 06.29PM, Jul 14CDC Cracks Down on Labs After Anthrax, Bird Flu Scares – Jonel Aleccia – NBC News

“Dr. Tom Frieden, director of the Centers for Disease Control and Prevention, on Friday announced an immediate moratorium on all shipments of biological materials from CDC biosecurity level 3 and level 4 labs until problems are addressed.”

Marine Mammals

Screen shot 2014-07-14 at 06.29PM, Jul 14 1How Dolphins’ Genetics Could Help Find Answers Into Mysterious Animal Die-Off – Sascha Cordner – WFSU

“A discovery into dolphin genetics may have brought research scientists one step closer to finding out the source of a mysterious animal die-off last year in the troubled Indian River Lagoon.”

Science and publishing

Screen shot 2014-07-14 at 12.45PM, Jul 14Retractions are coming thick and fast: it’s time for publishers to act – Adam Marcus and Ivan Oransky – The Guardian

“Another encouraging development is the rise of post-publication peer review, which has been made possible in recent years by the availability of papers online. Contributors to PubPeer, for example, have found signs of flawed or falsified results, leading to papers being retracted.”

Dr. Bik’s Picks

Screen shot 2014-07-14 at 06.34PM, Jul 14Whole genome and exome sequencing of monozygotic twins discordant for Crohn’s disease – Britt-Sabina Petersen – BMC Genomics

“We present a thorough genetic characterization of the sequenced individuals but detected no consistent differences within the twin pairs. “

Screen shot 2014-07-14 at 06.32PM, Jul 14How much science is there in new Planet of the Apes film? – Paul Rincon – BBC Science

“The latest instalment in the Planet of the Apes film franchise opens in the US on Friday. The rubber masks of the 60s and 70s films have been discarded in favour of motion capture suits and CGI. But how much did science inform the new movie’s portrayal of our close relatives?”

Screen shot 2014-07-14 at 06.31PM, Jul 14Domestication syndrome: White patches, baby faces and tameness explained by mild neural crest deficits – Science Daily

“Compared to their wild ancestors, domestic species are more tame, and they also tend to display a suite of other characteristic features, including floppier ears, patches of white fur, and more juvenile faces with smaller jaws.”

 

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Non-human microbiome, July 2014

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Kittens! And squid, sponges, acid mine drainage in someone’s backyard, soils, and sediments.

Cat microbiome

KittensDeep Illumina-Based Shotgun Sequencing Reveals Dietary Effects on the Structure and Function of the Fecal Microbiome of Growing Kittens – Oliver Deusch – PLOS ONE

“The present study… applied deep Illumina shotgun sequencing to identify the diet-associated functional potential and analyze taxonomic changes of the feline fecal microbiome.”

Squid microbiome

Squid albaGene-Swapping Mediates Host Specificity among Symbiotic Bacteria in a Beneficial Symbiosis – Alba A. Chavez-Dozal – PLOS ONE

“Our results demonstrate that multiple bacterial genetic elements can determine V. fischeri strain specificity between two closely related squid hosts, indicating how important genetic variation is for regulating conspecific beneficial interactions that are acquired from the environment.”

Sponge microbiome 

Review: Diversity and biotechnological potential of microorganisms associated with marine sponges – Fuerst JA – Applied Microbiol Biotechnol (Direct link not working)

“Here, we review recent progress in our understanding of this genetic diversity, its retrieval via culture and genomic approaches, and its implications for chemical diversity and other biotechnology applications of sponge microorganisms and their genes.”

Soils and sediments

StroudMetal(loid) bioaccessibility dictates microbial community composition in acid sulfate soil horizons and sulfidic drain sediments – Jackie Stroud – Environmental Science & Technology

“Microbial community compositions were determined for three soil horizons and drain sediments within an anthropogenically-disturbed coastal acid sulfate landscape using 16S rRNA gene tagged 454 pyrosequencing.”

Screen shot 2014-07-14 at 12.34PM, Jul 14Geochemical and microbiological response to oxidant introduction into reduced subsurface sediment from the Hanford 300 Area, WA – Elizabeth M Percak-Dennett and Eric E. Roden – Environmental Science & Technology

“Together these results indicate the potential for heterotrophic carbon metabolism in the reduced sediments, consistent with the proliferation of known heterotrophic taxa (e.g. Pseudomonadaceae, Burkholderiaceae, Clostridiaceae) inferred from 16S rRNA gene pyrosequencing.”

Brantner AMDResponse 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.”

Screen shot 2014-07-14 at 12.36PM, Jul 14New carbohydrate-active enzymes identified by screening two metagenomic libraries derived from the soil of a winter wheat field – A. Stroobants – Journal of Applied Microbiology

“The aim of this work was to discover new β-glucosidases by constructing two metagenomic DNA libraries from soil samples collected in winter and spring from a field of winter wheat.”

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Human microbiome, July 14

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Ethnic variation in vaginal microbiomes, effect of chemotherapy on human milk, response of (murine) microbiota to infection.

Oral microbiome

Screen shot 2014-07-14 at 12.23PM, Jul 14Advancements toward a Systems Level Understanding of the Human Oral Microbiome – Jeffrey S. Mclean – Frontiers in Cellular and Infection Microbiology

“This review will discuss some of the recent insights into the oral microbiome at a fundamental level, existing knowledge gaps, as well as challenges that have surfaced and the approaches to address them.”

Vaginal microbiome

Screen shot 2014-07-14 at 12.24PM, Jul 14Ethnic Variations in Cervical Cytokine Concentrations and Vaginal Flora During Pregnancy – Riana Dutt – American Journal of Reproductive Immunology

“Semi-quantitative vaginal cultures and concentrations of cervical cytokines were compared between Caucasian and non-Caucasian women.”

Gut microbiome

Screen shot 2014-07-14 at 12.25PM, Jul 14A functional metabolic map of Faecalibacterium prausnitzii, a beneficial human gut microbe – Almut Heinken – Journal of Bacteriology

“In this study, we present an integrated, iterative approach of computational modeling, in vitro experiments, metabolomics and genomic analysis to accelerate the identification of metabolic capabilities for poorly characterized (anaerobic) microorganisms.”

Pregnancy and birth

Screen shot 2014-07-14 at 12.26PM, Jul 14Effect of chemotherapy on the microbiota and metabolome of human milk, a case report – Camilla Urbaniak – Microbiome

“Mature milk was collected every two weeks over a four month period from a lactating woman undergoing chemotherapy for Hodgkin’s lymphoma. Mature milk was also collected from healthy lactating women for comparison. Microbial profiles were analyzed by 16S sequencing and the metabolome by gas chromatography-mass spectrometry.”

Animal models

Clara Belzer miceDynamics of the Microbiota in Response to Host Infection – Clara Belzer – PLOS ONE

“Employing a murine model of infectious colitis with the pathogen Citrobacter rodentium, we generated a 2-month time-series of 16S rDNA gene profiles, and quantitatively cultured commensals, from multiple intestinal sites in infected and uninfected mice. “

Prune juice animal modelCarbohydrate-Free Peach (Prunus persica) and Plum (Prunus domestica) Juice Affects Fecal Microbial Ecology in an Obese Animal Model – Giuliana D. Noratto – PLOS ONE

“Fecal samples were obtained after 11 weeks of fruit or control juice administration. Real-time PCR and 454-pyrosequencing were used to evaluate changes in fecal microbiota. Over 1,500 different Operational Taxonomic Units at 97% similarity were detected in all rats.”

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Microbiome and general science digest, July 11

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Most recent results from American gut, a metagenomics pipeline, arsenic toxicity, polio and dengue vaccines, and pregnancy urine metabolomics to predict preterm birth.

Human gut microbiome

American GutAmerican Gut releases latest results and pipeline – Jeff Leach – American Gut

“The latest American Gut results are out and we’re very excited to share them with the American Gut community. We now have sequencing and analysis data from 3,238 participants, and as of today, this data equates to 101 million DNA sequences and 27 gigabytes of sequencing information.”

Screen shot 2014-07-11 at 04.27PM, Jul 11Place of upbringing in early childhood as related to inflammatory bowel diseases in adulthood: a population-based cohort study in Northern Europe – Signe Timm – European Journal of Epidemiology

“This study suggests a protective effect from livestock farm living in early childhood on the occurrence of IBD in adulthood, however only among subjects born after 1952. We speculate that lower microbial diversity is an explanation for the findings.”

Pregnancy and birth

Urinary pretermUrinary metabolic profiles in early pregnancy are associated with preterm birth and fetal growth restriction in the Rhea mother–child cohort study – Léa Maitre – BMC Medicine

“Here we used an exploratory metabolic profiling approach (metabolomics) to investigate the association between birth outcomes and metabolites in maternal urine collected early in pregnancy as part of the prospective mother–child cohort Rhea study. “

Metagenomics

MedusaMetagenomic Data Utilization and Analysis (MEDUSA) and Construction of a Global Gut Microbial Gene Catalogue – Fredrik H. Karlsson, Intawat Nookaew, Jens Nielsen – PLOS Computational Biology

“Here we present the bioinformatics pipeline MEDUSA that facilitates analysis of metagenomic reads at the gene and taxonomic level. We also constructed a global human gut microbial gene catalogue by combining data from 4 studies spanning 3 continents. “

Proteomics

Proteomics Staph aureusGenomics and Proteomics Provide New Insight into the Commensal and Pathogenic Lifestyles of Bovine and Human-associated Staphylococcus epidermidis strains – Kirsi Savijoki – Journal of Proteome Research

“Pilot experimental infection studies indicated that while ATCC12228 was able to infect bovine host, the PM221 strain caused more severe clinical signs. “

Dengue

Demanou DengueEvidence of Dengue Virus Transmission and Factors Associated with the Presence of Anti-Dengue Virus Antibodies in Humans in Three Major Towns in Cameroon – Maurice Demanou – PLOS Neglected Tropical Diseases

“Sera were screened for anti-dengue virus IgG and IgM antibodies. Risk factors of seropositivity were tested using logistic regression methods with random effects.”

Carrasco DenguePredictive Tools for Severe Dengue Conforming to World Health Organization 2009 Criteria – Luis R. Carrasco – PLOS Neglected Tropical Diseases

“Higher risk of severe dengue (SD) was associated with female gender, lower than normal hematocrit level, abdominal distension, vomiting and fever on admission. “

Infection and host response

Screen shot 2014-07-11 at 03.35PM, Jul 11Development of Fatal Intestinal Inflammation in MyD88 Deficient Mice Co-infected with Helminth and Bacterial Enteropathogens – Libo Su – PLOS Neglected Tropical Diseases

“We found that MyD88 knockout mice co-infected with H. polygyrus and C. rodentium developed more severe intestinal inflammation and elevated mortality compared to the wild-type mice.”‘

Screen shot 2014-07-11 at 04.28PM, Jul 11Distinct Lipid A Moieties Contribute to Pathogen-Induced Site-Specific Vascular Inflammation – Connie Slocum – PLOS Pathogens

“our results point to a pivotal role for activation of the non-canonical inflammasome in P. gingivalis infection and demonstrate that P. gingivalis evades immune detection at TLR4 facilitating chronic inflammation in the vasculature. “

Dengue

Dengue vaccine lancetClinical efficacy and safety of a novel tetravalent dengue vaccine in healthy children in Asia: a phase 3, randomised, observer-masked, placebo-controlled trial – Maria Rosario Capeding – The Lancet

“Our findings show that dengue vaccine is efficacious when given as three injections at months 0, 6, and 12 to children aged 2–14 years in endemic areas in Asia, and has a good safety profile. “

Also see comment: Dengue vaccines: dawning at last? – Annelies Wilder-Smith – The Lancet

Poliovirus

Jacob John polioEffect of a single inactivated poliovirus vaccine dose on intestinal immunity against poliovirus in children previously given oral vaccine: an open-label, randomised controlled trial – Jacob John – The Lancet

“The substantial boost in intestinal immunity conferred by a supplementary dose of IPV given to children younger than 5 years who had previously received OPV shows a potential role for this vaccine in immunisation activities to accelerate eradication and prevent outbreaks of poliomyelitis.”

Also see comment: Polio endgame management: focusing on performance with or without inactivated poliovirus vaccine – Kimberly M Thompson – The Lancet

Microbes in the News

Screen shot 2014-07-11 at 04.28PM, Jul 11 1How Gross Is Your Phone? A Motherboard Science Experiment – Jason Koebler – Motherboard

“All I wanted to do was recreate a relatively simple study I had just written about. Instead, I ended up creating something vaguely dangerous, which mortified the director of a local DIY biology lab. Here’s what happens when you perform experiments on your coworkers.”

Arsenic metabolism

Screen shot 2014-07-11 at 04.29PM, Jul 11Lung tumors in mice induced by “whole-life” inorganic arsenic exposure at human-relevant doses – Michael P. Waalkes – Archives of Toxicology

“Breeder male and female CD1 mice were exposed to 0, 50, 500 or 5,000 ppb arsenic (as sodium arsenite) in the drinking water for 3 weeks prior to breeding, during pregnancy and lactation, and after weaning (at week 3) groups of male and female offspring (initial n = 40) were exposed for up to 2 years.”

Dr. Bik’s Picks

Scorpions are master architects, according to new research – Science Daily

“The burrows made by scorpions follow a very sophisticated design, beginning with a short, vertical entrance shaft that flattened out a few centimeters below the surface into a horizontal platform, new research has found.”

Beach Sand Used To Make A Battery That Lasts Three Times Longer – Douglas Main – Popular Science

“Sink your toes into this: Beach sand can be used to make lithium-ion batteries that last three times longer than current models, according to a study published in the journal Scientific Reports.”

World Now “A Safer Place”, thanks to creation of Potential Pandemic Virus – The Allium

“Yes, I get your point that they could potentially kill millions of people and hospitalise millions more, causing untold human suffering and extraordinary economic damage, but think of all the advantages to the creation of these bugs”.

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