Category Archives: Human reproductive or urinary

Human microbiome digest, September 16, 2014

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Still catching up after my vacation, but almost there!

Some general microbiome reviews, using saliva to track human evolution, probiotics that actually change the microbiome, and several animal model studies.

 

General microbiome reviews

Which is more important for classifying microbial communities: who’s there or what they can do? – Zhenjiang Xu – ISME Journal

“… might we not instead expect that function would be substantially more important for classifying biologically meaningful groups of samples than who is providing those functions? “

Microbiome analysis – from technical advances to biological relevance – Michelle I. Smith – F1000Prime Reports

“Here, we introduce techniques that go beyond identifying the taxa present within a sample and examine the biological function of the microbiome or the host-microbiome interaction.”

From barcoding single individuals to metabarcoding biological communities: towards an integrative approach to the study of global biodiversity – Melania E. Cristescu – Trends in Ecology & Evolution

“DNA-based species identification, known as barcoding, transformed the traditional approach to the study of biodiversity science. “

Human oral microbiome

Global analysis of saliva as a source of bacterial genes for insights into human population structure and migration studies – Karsten Henne – BMC Evolutionary Biology

“By focussing on the house-keeping gene gdh .., on the virulence gene gtf .. of mitis-streptococci and on the 16S-23S rRNA internal transcribed spacer (ITS) region of the Fusobacterium nucleatum/periodonticum-group we here tested the hypothesis that bacterial genes from human saliva have the potential for distinguishing human populations.’

Microbial community in persistent apical periodontitis: a 16S rRNA gene clone library analysis – M. N. Zakaria – International Endodontic Journal

“Whilst a diverse bacterial species were observed in the persistent apical lesions, some characteristic patterns of bacterial community were found in the symptomatic lesions. “

The Adenoid Microbiome in Recurrent Acute Otitis Media and Obstructive Sleep Apnea – Carolyn P. Ojano-Dirain – Otolaryngology – Head and Neck Surgery

“Microbes are present on all adenoid specimens, however, the microbial profile differs between recurrent AOM and OSA.”

Human gut microbiome

Susceptibility to Campylobacter Infection Is Associated with the Species Composition of the Human Fecal Microbiota – Johan Dicksved – mBio

“Here we address this by prospectively studying the gut microbiota composition before, during, and after natural Campylobacter infection in exposed poultry abattoir workers.”

Eukaryote Culturomics of the Gut Reveals New Species – Nina Gouba, Didier Raoult, Michel Drancourt – PLOS ONE

“We further explored this repertoire using PCR-sequencing and culture in seven individuals living in four tropical countries. A total of 41 microeukaryotes including 38 different fungal species and three protists were detected. “

Review: Decade in review—gut microbiota: The gut microbiota era marches on – Francisco Guarner – Nature Reviews Gastroenterology & Hepatology

“Research on the gut microbial communities harboured in the human gut is progressing rapidly owing to the availability of novel and reliable tools for analysis.”

Modulation of Fecal Clostridiales Bacteria and Butyrate by Probiotic Intervention with Lactobacillus paracasei DG Varies among Healthy Adults – Chiara Ferrario – Journal of Nutrition

“High-throughput 16S ribosomal RNA gene sequencing was used to characterize the fecal microbiota in healthy adults (23–55 y old) of both sexes, before and after 4 wk of daily consumption of a capsule containing at least 24 billion viable Lactobacillus paracasei DG cells”

Review: The gut microbiota, bacterial metabolites and colorectal cancer – Petra Louis, Georgina L. Hold & Harry J. Flint – Nature Reviews Microbiology

“In this Review, we discuss the relationship between diet, microbial metabolism and CRC and argue that the cumulative effects of microbial metabolites should be considered in order to better predict and prevent cancer progression.”

Changes of the human gut microbiome induced by a fermented milk product – Patrick Veiga – Nature Scientific Reports

“Our data challenge the view that microbes ingested with food have little impact on the human GM functioning and rather provide support for beneficial health effects.”

Gut Microbiome and Multiple Sclerosis – Pavan Bhargava, Ellen M. Mowry – Current Neurology and Neuroscience Reports

“We examine the different sources of information linking the gut microbiota to multiple sclerosis and examine the future avenues for utilizing the knowledge of the gut microbiome to potentially treat and prevent multiple sclerosis.”

Microbial Modulation of Insulin Sensitivity – Muhammad Tanweer Khan, Max Nieuwdorp, Fredrik Bäckhed – Cell Metabolism

“The gut microbiota has emerged as an integral factor that impacts host metabolism and has been suggested to play a vital role in metabolic diseases such as obesity, insulin resistance, type 2 diabetes, and cardiovascular disease.”

Gut Microbial Community Structure and Complications After Kidney Transplantation: A Pilot Study – Lee, John R – Transplantation

“We characterized bacterial composition by polymerase chain reaction amplification of the 16S rRNA V4-V5 variable region and deep sequencing using the Illumina MiSeq platform.’

Human genital microbiome

Association between cigarette smoking and the vaginal microbiota: a pilot study – Rebecca M Brotman – BMC Infectious Diseases

“Smokers had a lower proportion of vaginal Lactobacillus spp. compared to non-smokers.”

Pregnancy and birth

Human Breast Milk – The Magic In The Microbiome – Science20

“Ma et al (2014 submitted manuscript) recently postulated that the opportunistic pathogen such as Staphylococcus aureus, which has been confirmed to exist in the human milk microbiome, is normally suppressed by a network of beneficial bacteria coexisted in the breast milk microbiome, but may become source of infectious mastitis when the host environment permits.”

Animal models of human microbiome research

Antibiotic Treatment of Pregnant Non-Obese Diabetic Mice Leads to Altered Gut Microbiota and Intestinal Immunological Changes in the Offspring – N. Tormo-Badia – Scandinavian Journal of Immunology

“we found a differential clustering of gut microbiota in the offspring from NOD mothers treated with antibiotics during gestation compared with offspring from control mothers.”

Shifts in microbiota species and fermentation products in a dietary model enriched in fat and sucrose – U. Etxeberria – Beneficial Microbes

“The aim of the present study was to identify gut microbiota dysbiosis and associated metabolic changes produced in male Wistar rats fed a HFS diet for 6 weeks and compare it with the basal microbial composition.”

The short chain fatty acids, butyrate and propionate, have differential effects on the motility of the guinea pig colon – Norm R. Hurst – Neurogastroenterology & Motility

“We hypothesized that the effect of SCFAs on colonic motility varies with chain length and aimed to determine the effects of SCFAs on propagating and non-propagating contractions of guinea pig proximal and distal colon.”

Small Bowel Resection Induces Long-Term Changes in the Enteric Microbiota of Mice – J. Sommovilla – Journal of Gastrointestinal Surgery

“Bowel resection induces long-term changes in the microbial community of the murine ileum, but not at more distal sites of the gastrointestinal tract. “

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Human microbiome digest, August 25, 2014

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Oral microbiome in the settings of periodontitis, smoking and antibiotic resistance, respiratory microbiome in Cystic Fibrosis, a decade of molecular papers on vaginal microbiome, and gut bacteria protecting against food allergies.

Oral microbiome

* Microbial Signature Profiles of Periodontally Healthy and Diseased Patients – Talita Gomes Baêta Lourenço – Journal of Clinical Periodontology

“Subgingival biofilm was obtained from patients with periodontal health (27), gingivitis (11), chronic periodontitis (35) and aggressive periodontitis (24), and analyzed for the presence of >250 species/phylotypes using HOMIM. “

Smoking decreases structural and functional resilience in the subgingival ecosystem – Vinayak Joshi – Journal of Clinical Periodontology

“16S cloning and sequencing was used for bacterial identification and multiplexed bead-based flow cytometry was used to quantify the levels of 27 immune mediators.”

Extended-spectrum beta-lactamase-producing bacteria are not detected in supragingival plaque samples from human fecal carriers of ESBL-producing Enterobacteriaceae – Arne Søraas – Journal of Oral Microbiology

“No ESBL-producing bacteria or ESBL genes were detected using culture-based and molecular methods. “

Clonality of bacterial consortia in root canals and subjacent gingival crevices – Nipuna B. Parahitiyawa – Journal of Investigative and Clinical Dentistry

“The four niches studied yielded 186 clones representing 54 phylotypes. Clone library comparisons using LIBSHUFF software indicated that each niche was inhabited by a unique flora. “

Respiratory microbiome

* Antimicrobial resistance in the respiratory microbiota of people with cystic fibrosis –
Laura J Sherrard – The Lancet

“Strategies to manage antimicrobial resistance consist of new antibiotics or localised delivery of antimicrobial agents, iron sequestration, inhibition of quorum-sensing, and resistome analysis.”

Evidence that Intraspecific Trait Variation among Nasal Bacteria Shapes the Distribution of Staphylococcus aureus – Ben Libberton – Infection and Immunity

“We characterized S. aureus growth inhibition by the culturable bacterial aerobe consortia of 60 nasal microbiomes, and this revealed intraspecific variation in growth inhibition and that inhibitory isolates clustered within communities that were culture negative for S. aureus. “

Gary Huffnagle: rewriting the rules on the lung microbiome – David Holmes – The Lancet

“The ideas being generated by Huffnagle at the moment are all about the lung microbiome and its role in the pathogenesis of everything from chronic obstructive pulmonary disease (COPD) to asthma, and they’re starting to make waves.”

Vaginal microbiome

* The Vaginal Microbiota: What Have We Learned after a Decade of Molecular Characterization? – Janneke H. H. M. van de Wijgert – PLOS ONE

“We conducted a systematic review of the Medline database … to determine if consistent molecular vaginal microbiota (VMB) composition patterns can be discerned after a decade of molecular testing, and to evaluate demographic, behavioral and clinical determinants of VMB compositions.”

Gut microbiome

Modelling the Emergent Dynamics and Major Metabolites of the Human Colonic Microbiota – Helen Kettle – Environmental Microbiology

“We present here a first attempt at modelling microbial dynamics in the human colon incorporating both uncertainty and adaptation. “

Animal models of human microbiome

Commensal bacteria protect against food allergen sensitization – Andrew T. Stefka – PNAS USA

“By selectively colonizing gnotobiotic mice, we demonstrate that the allergy-protective capacity is conferred by a Clostridia-containing microbiota. “

Pregnancy and Birth

Researcher Granted $1 Million to Study Deadly Bacteria Passed to Babies From 25 Percent of Mothers – Infection Control Today

“Narayana Sthanam, PhD, professor of structural biology in the Department of Optometry, has been awarded a four-year, $1 million R01 grant from the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, to further Group B Streptococcus research.”

Microbiome News

* Satire: Study Reveals Microbiome To Be Master-Controller Of All Humanity – The Allium

“Science has already found out that your microbiome at birth decides your taste in clothes and music, whether you are going to be great footballer like David Beckham or a great political leader like Sarah Palin.”

9 questions you were too grossed out to ask about the bacteria living on you – Susannah Locke – Vox

“What researchers have discovered is that our bodies are essentially complex ecosystems of tiny living things. “

Interview with Prof. Yolanda Sanz, project coordinator of My New Gut – Kristina Campbell – Gut Microbiota For Health

“Professor Yolanda Sanz has been appointed MyNewGut’s project coordinator and leads the project’s human intervention trials on the gut microbiome’s ability to metaolise (sic) nutrients and influence energy balance. “

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Microbiome Digest, August 22, 2014

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The microbiome of the human eye,  chronic lung diseases, ticks, trout, the air in wineries, and Bik’s Picks. Have a good weekend!
Pregnancy and birth

The human microbiome and the great obstetrical syndromes, a new frontier in maternal fetal medicine – Ido Solt – Best Practice & Research Clinical Obstetrics & Gynaecology

“The transmission of maternal microbiomes to the neonate, according to vaginal delivery or cesarean section, is shown to affect health from birth to adulthood.”

Human skin microbiome

Considerations in Understanding the Ocular Surface Microbiome – Michael E. Zegans – American Journal of Ophthalmology

“In ophthalmology, the question naturally arises as to whether or not the ocular surface, like other mucous membrane surfaces, has a resident microbiota, and, if so, what role it plays in ocular surface physiology. This question has provoked much debate over many years. “

Human respiratory microbiome
* The role of the microbiome in exacerbations of chronic lung diseases – Robert P Dickson – The Lancet

“We propose that exacerbations are occasions of respiratory tract dysbiosis—a disorder of the respiratory tract microbial ecosystem with negative effects on host biology.”

Human gut microbiome

* Starving our Microbial Self: The Deleterious Consequences of a Diet Deficient in Microbiota-Accessible Carbohydrates – Erica D. Sonnenburg, Justin L. Sonnenburg – Cell Metabolism

“The low-MAC Western diet results in poor production of gut microbiota-generated short-chain fatty acids (SCFAs), which attenuate inflammation through a variety of mechanisms in mouse models. “

Human vaginal microbiome

Rectal Lactobacillus Species and Their Influence on the Vaginal Microflora: A Model of Male-to-Female Transsexual Women – Ljubomir Petricevic – The Journal of Sexual Medicine

“We undertook this observational study to characterize the Lactobacillus species present in the neovagina and rectum of male-to-female transsexual women and to determine the degree of neovaginal-rectal co-colonization in order to gain a better understanding of the potential role of the gut as a reservoir for genital lactobacilli.”

Animal models of microbiome research

Perinatal antibiotic-induced shifts in gut microbiota have differential effects on inflammatory lung diseases – Shannon L. Russell – Journal of Allergy and Clinical Immunology

“Disease severity was assessed by measuring lung inflammation, pathology, cytokine responses, and serum antibodies. Microbial community analyses were performed on stool samples via 16S ribosomal RNA pyrosequencing and correlations between disease severity and specific bacterial taxa were identified.”

Animal microbiome

The composition and transmission of microbiome in hard tick, Ixodes persulcatus, during blood meal – Xue-Chao Zhang – Ticks and Tick-borne Diseases

“By 16S rRNA Illumina sequencing, we investigated the microbiome of I. persulcatus and assessed the variation of the microbiome before and after blood feeding.”

Diet type dictates the gut microbiota and the immune response against Yersinia ruckeri in rainbow trout (Oncorhynchus mykiss) – Hans-Christian Ingerslev – Fish & Shellfish Immunology

“This study investigated the influence of the rainbow trout (Oncorhynchus mykiss) commensal intestinal microbiota in connection to an experimental Yersina ruckeri infection, the causative agent of enteric redmouth disease.”

Food microbiology

* Microbial communities in air and wine of a winery at two consecutive vintages – Fátima Pérez-Martín – International Journal of Food Microbiology

“The microbial composition was determined by using both a culture-dependent method and a culture-independent method, PCR-denaturing gradient gel electrophoresis (PCR-DGGE).”

Metabolomics

* Microbial catabolism of procyanidins by human gut microbiota – Keqin Ou – Molecular Nutrition & Food Research

“The objective of this study was to identify and quantify the microbial metabolites of procyanidins after anaerobic fermentation with human microbiota.”

Bioinformatics

* Defining the Estimated Core Genome of Bacterial Populations Using a Bayesian Decision Model – Andries J. van Tonder – PLOS Computational Biology

“The aim of our study was to develop a model to estimate the bacterial core genome from next-generation whole genome sequencing data and use this model to identify novel genes associated with important biological functions. “

* Comparative Analysis of Functional Metagenomic Annotation and the Mappability of Short Reads – Rogan Carr, Elhanan Borenstein – PLOS ONE

“Overall, our findings provide a first comprehensive evaluation of the capabilities and limitations of functional metagenomic annotation, providing crucial goal-specific best-practice guidelines to inform future metagenomic research.”

ExaBayes: Massively Parallel Bayesian Tree Inference for the Whole-Genome Era
Andre J. Aberer – Molecular Biology and Evolution

“We introduce a novel, user-friendly software package engineered for conducting state-of-the-art Bayesian tree inferences on datasets of arbitrary size.”

Microbes in the news

Behold 50 shades of Gross: A guide to Germaphobia! – Katherine Dahlhausen – MicroBEnet

“So logically, I began researching germaphobic practices. Some of them are just too good not to share! “

California Trees Nailed As The Source Of Mystery Infections – Nancy Shute – NPR

“”We had a good idea that the fungus was going to be associated with trees,” says Deborah Springer, a postdoctoral fellow at Duke University who studies C. gatti. “

Bik’s Picks

Pulling teeth from history: DNA from ancient teeth can help to yield information about our ancestors’ health, diet and diseases – Philip Hunter – EMBO Reports

“Teeth have proven to be an excellence source of ancient DNA. New analytical tools are helping to exploit this treasure trove to address questions about the link between diet and health, and the impact of historical epidemics with clear relevance for human health today.”

Ten Simple Rules of Live Tweeting at Scientific Conferences – Sean Ekins, Ethan O. Perlstein – PLOS Computational Biology

“Increasingly, some scientists are using Twitter as a vehicle to summarize presentations and posters at conferences in real time, which is defined as “live tweeting.””

Why the World Smells Different After It Rains – Behold, the wonders of petrichor.
Megan Garber – The Atlantic

“In the video above, PBS’s Joe Hanson describes the biology that leads to petrichor.”

Scientist Mistakenly Does “Dry-Ice Bucket Challenge” – The Allium

“Sad news has come to us today at The Allium, when we learned that scientist Dr. Liv Good, has mistakenly carried out a Dry-Ice Bucket challenge.”

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Human microbiome digest, August 19, 2014

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Lots of oral and gut microbiome papers today – Alzheimer’s, probiotics, chemotherapy and radiation.

Oral microbiome

Review: The Microbiome and Disease: Reviewing the Links between the Oral Microbiome, Aging, and Alzheimer’s Disease – Deborah K. Shoemark – Journal of Alzheimer’s Disease

“Evidence linking oral bacteria to Alzheimer’s disease (AD) is discussed in the context of aging, drawing together data from epidemiological, experimental, genetic, and environmental studies. “

* Human oral viruses are personal, persistent and gender-consistent – Shira R Abeles – ISME Journal

“To improve our understanding of the DNA viruses that inhabit the human oral cavity, we examined saliva from a cohort of eight unrelated subjects over a 60-day period. “

* Predictive modeling of gingivitis severity and susceptibility via oral microbiota – Shi Huang – ISME Journal

“In diseased plaque microbiota, 27 bacterial genera changed in relative abundance and functional genes including 33 flagellar biosynthesis-related groups were enriched.”

Phylogenetic and functional gene structure shifts of the oral microbiomes in periodontitis patients – Yan Li – ISME Journal

“Here, we examined the phylogenetic and functional gene differences between periodontal and healthy individuals using MiSeq sequencing of 16S rRNA gene amplicons and a specific functional gene array”

Perspective: Fungal-bacterial interactions and their relevance to oral health: linking the clinic and the bench – Patricia I. Diaz – Frontiers in Cellular and Infection Microbiology

“We highlight the need to conduct longitudinal clinical studies to simultaneously characterize the bacterial and fungal components of the human oral microbiome in health and during disease progression.”

Effect of an oxygenating agent on oral bacteria in vitro and on dental plaque composition in healthy young adults – Mercedes Fernandez y Mostajo – Frontiers in Cellular and Infection Microbiology

“During the experiment individuals used AX mouthwash twice daily in absence of other oral hygiene measures. The microbiological composition of plaque was assessed by 16S rRNA gene amplicon sequencing.”

* Review: Advancements 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.”

Gut microbiome

* Xylan utilization in human gut commensal bacteria is orchestrated by unique modular organization of polysaccharide-degrading enzymes – Meiling Zhang – PNAS USA

“Here we demonstrate that two human gut commensal Bacteroides are equipped with unique enzymes that allow degradation of xylan, a common hemicellulose in human diets.”

Evaluation of bifidobacterial community composition in the human gut by means of a targeted amplicon sequencing (ITS) protocol – Christian Milani – FEMS Microbiology Ecology

“Here, we define the internal transcribed spacer (ITS) sequences of all currently known Bifidobacterium taxa, providing a Bifidobacterium-specific primer pair that targets a hyper-variable region within the ITS suitable for precise taxonomic identification of all 48 so far recognized members of the Bifidobacterium genus.”

* Multi-omics analysis of Inflammatory Bowel Diseases – Hu Huang – Immunology Letters

“There is strong evidence of interactions between host genotype, environment, and gut microbiome profile in IBD.”

The methylome of the gut microbiome: disparate Dam methylation patterns in intestinal Bacteroides dorei – Michael T. Leonard – Frontiers in Microbiology

“Here metagenomic sequencing using the Pacific Biosciences platform allowed for rapid identification of bacterial GATC methylation status of a bacterial species in human stool samples. “

Perspective: Imposition of encapsulated non-indigenous probiotics into intestine may disturb human core microbiome – Abolfazl Barzegari – Frontiers in Microbiology

“..we envision that multi-probiotic therapy and holistic personalized microbiome supplements may be scientifically justified and valued in individualized probiotic designs and even targeted therapy of life-threatening diseases such as cancers in the future. “

Editorial: gut microbiota and chemotherapy- or radiation-induced gastrointestinal mucositis – M. R. Ferreira and H. J. N. Andreyev – Alimentary Pharmacology & Therapeutics

“Studies in those undergoing cancer therapy will lead to a new era in the treatment and prevention of the currently dreadful GI toxicity suffered by so many patients, and what we learn will almost certainly bring important insights to many other GI disorders.”

Respiratory microbiome

Cell-associated bacteria in the human lung microbiome – Robert P Dickson – Microbiome

“We present a novel methodological and analytical approach to the localization of lung microbiota and show that the prominent members of the lung microbiome are cell-associated, potentially via biofilms, cell adhesion, or intracellularity.”

Vaginal microbiome

A Systems Biology Approach Investigating the Effect of Probiotics on the Vaginal Microbiome and Host Responses in a Double Blind, Placebo-Controlled Clinical Trial of Post-Menopausal Women – Jordan E. Bisanz – PLOS ONE

“Analysis using 16S rRNA sequencing and metabolomics profiling revealed that the relative abundance of Lactobacillus was increased following probiotic administration as compared to placebo, which was weakly associated with an increase in lactate levels. “

Lactobacillus-dominated cervicovaginal microbiota associated with reduced HIV/STI prevalence and genital HIV viral load in African women – Hanneke Borgdorff – ISME Journal

“In this study, cervical samples of 174 Rwandan female sex workers were analyzed cross-sectionally using a phylogenetic microarray. “

* also tweeted by @MicrobiomDigest (yup, that’s me).

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Human microbiome digest, August 5, 2014

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Lots of microbiome papers today, so I will split it up into three posts. Here you will find papers on human gut, respiratory, oral, and vaginal microbiomes, as well as animal models.

Pregnancy and Birth

Prevalence and Clinical Significance of Sterile Intra-amniotic Inflammation in Patients with Preterm Labor and Intact Membranes – Roberto Romero – American Journal of Reproductive Immunology

“The purpose of this study was to (i) determine the prevalence and clinical significance of sterile intra-amniotic inflammation and (ii) examine the relationship between amniotic fluid (AF) concentrations of high mobility group box-1 (HMGB1) and the interval from amniocentesis to delivery in patients with sterile intra-amniotic inflammation.”

A Holobiont Birth Narrative: The Epigenetic Transmission of the Human Microbiome –
Scott F. Gilbert – Frontiers in Genetics

“Birth is nothing less than the passage from one set of symbiotic relationships to another.”

Fecal Short Chain Fatty Acids of Very Low Birth Weight Preterm Infants Fed Expressed Breast Milk or Formula – Pourcyrous, M.; Nolan, V.G.; Goodwin, A.; Davis, S.L.; Buddington, R.K. – Journal of Pediatric Gastroenterology & Nutrition

“ Ion chromatography was used to measure fecal SCFAs (acetate, formate, propionate, butyrate, and isobutyrate), lactate, and chloride in fresh stool samples collected from 32 preterm infants”

Human mouth microbiome

Microbial community in persistent apical periodontitis: a 16S rRNA gene clone library analysis – M. N. Zakaria – International Endodontic Journal

“DNA was directly extracted from each sample and the microbial composition was comprehensively analyzed using clone library analysis of the 16S rRNA gene”

 Respiratory microbiome

A large genomic island allows Neisseria meningitidis to utilize propionic acid, with implications for colonization of the human nasopharynx – Maria Chiara E. Catenazzi, Helen Jones, Iain Wallace, Jacqueline Clifton, James P. J. Chong, Matthew A. Jackson, Sandy Macdonald, James Edwards andJames W. B. Moir – Molecular Microbiology

“Data from classical microbiological and sequence-based microbiome studies provide several lines of supporting evidence that N. meningitidis colonization is correlated with propionic acid generating bacteria, with a strong correlation between prp-containing Neisseria and propionic acid generating bacteria from the genus Porphyromonas, and that this may explain adolescent/adult colonization by N. meningitidis.”

Analysis of Culture-Dependent vs. Culture-Independent Techniques for the Identification of Bacteria in Clinically-Obtained Bronchoalveolar Lavage Fluid – Robert P. Dickson – Journal of Clinical Microbiology

“We analyzed forty six clinically-obtained bronchoalveolar lavage (BAL) specimens from symptomatic and asymptomatic lung transplant recipients both by culture (using a clinical microbiology laboratory protocol) and by bacterial 16S rRNA gene pyrosequencing. “

Vaginal microbiome

Differences in vaginal microbiome in African American women versus women of European ancestry – Jennifer M. Fettweis – Microbiology

“we performed 16S rRNA gene survey to compare the microbiomes of vaginal samples from 1,268 African American women and 416 women of European ancestry. Our results confirmed significant differences in the vaginal microbiomes of the two groups and identified several taxa relevant to these differences.”

Human gut microbiome

Unraveling the mechanisms underlying associations between the microbiome and gastrointestinal malignancies – Tiffany L. Weir – Translational Gastrointestinal Cancer

“While many reviews have focused on research identifying microbial signatures associated with malignancies, including changes in diversity or evenness of GI microbial communities and depletion or overrepresentation of particular bacterial groups; this comprehensive review emphasizes research that explores the cause rather than effects of microbe-malignancy relationships.”

Animal models of human microbiome

Transfer of gut microbiota from lean and obese mice to antibiotic-treated mice – Merete Ellekilde, Ellika Selfjord, Christian S. Larsen, Maja Jakesevic, Ida Rune, Britt Tranberg, Finn K. Vogensen, Dennis S. Nielsen, Martin I. Bahl, Tine R. Licht, Axel K. Hansen & Camilla H. F. Hansen – Nature Scientific Reports

“To date, most studies of gut microbiota transfer are performed in germ-free mice. In the studies presented, it was tested whether an antibiotic treatment approach could be used instead. “

Postnatal Prebiotic Fiber Intake in Offspring Exposed to Gestational Protein Restriction Has Sex-Specific Effects on Insulin Resistance and Intestinal Permeability in Rats – Megan C. Hallam and Raylene A. Reimer – Journal of Nutrition

“At 24 wk of age, glucose tolerance, body composition, satiety hormones, gut microbiota, and markers of intestinal permeability were measured in the offspring. “

A polyphenol-rich cranberry extract protects from diet-induced obesity, insulin resistance and intestinal inflammation in association with increased Akkermansia spp. population in the gut microbiota of mice – Fernando F Anhê – Gut

“CE exerts beneficial metabolic effects through improving HFHS diet-induced features of the metabolic syndrome, which is associated with a proportional increase in Akkermansia spp. population.”

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Human microbiome, July 22

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Transcriptome in periodontitis, metabolomic analysis of breath in IBD patients, cystic fibrosis microbiome, and Clostridium difficile.

Human microbiome general

Review: Deciphering the tête-à-tête between the microbiota and the immune system – Neeraj K. Surana and Dennis L. Kasper – Journal of Clinical Investigation

“In this Review, we discuss the current state of knowledge regarding the role of the intestinal microbiota in immunologic development, highlighting mechanistic principles that can guide future work.”

Meeting report: Human microbiome science: vision for the future, Bethesda, MD, July 24 to 26, 2013 – Jacques Ravel and many others – Microbiome

“This report summarizes the presentations but also describes what is needed for human microbiome research to move forward and deliver medical translational applications.”

Metabolomics

Metabolomic analysis of breath volatile organic compounds reveals unique breathprints in children with inflammatory bowel disease: a pilot study – N. Patel – Alimentary Pharmacology & Therapeutics

“Exhaled breath was collected and analysed using a selective ion flow tube mass spectroscopy (SIFT-MS) to identify new markers or patterns of IBD.”

Metabolites related to gut bacterial metabolism, peroxisome proliferator-activated receptor-alpha activation, and insulin sensitivity are associated with physical function in functionally-limited older adults – Michael S. Lustgarten – Aging Cell

“Collectively, these data suggest that gut microbial metabolism, PPAR-α activation, and insulin sensitivity may be involved in mechanisms that underlie physical function in functionally-limited older adults.”

Oral microbiome

Community-wide transcriptome of the oral microbiome in subjects with and without periodontitis – Ana E Duran-Pinedo – ISME J

“We report here the in situ genome-wide transcriptome of the subgingival microbiome in six periodontally healthy individuals and seven individuals with periodontitis.”

Respiratory microbiome

Predominant pathogen competition and core microbiota divergence in chronic airway infection – Geraint B Rogers – ISME Journal

“..we analysed 16S rRNA gene pyrosequencing data generated previously from 60 adult bronchiectasis patients, whose airway microbiota was dominated by either P. aeruginosa or H. influenzae.”

Pyrosequencing reveals transient cystic fibrosis lung microbiome changes with intravenous antibiotics – Daniel J. Smith – European Respiratory Journal

“Microbial community profiles were derived through analysis of bacterial-derived 16S ribosomal RNA by pyrosequencing and changes over time were compared.”

Review: Respiratory microbiota: addressing clinical questions, informing clinical practice – Geraint B Rogers – Thorax

“In this article, we set out the key principles underpinning microbiota research in respiratory contexts and provide practical guidance on how best such studies can be designed, executed and interpreted. “

Propionibacterium-Produced Coproporphyrin III Induces Staphylococcus aureus Aggregation and Biofilm Formation – Michael S. Wollenberg – mBio

“We observed that crude extracts of cell-free conditioned medium from Propionibacterium spp. induce S. aureus aggregation in culture. “

Gut microbiome

Reset of a critically disturbed microbial ecosystem: faecal transplant in recurrent Clostridium difficile infection – Susana Fuentes – ISME Journal

“Global composition and network analysis of the microbiota was performed in faecal samples from nine patients with recurrent CDI. Analyses were performed before and after duodenal donor faeces infusion, and during a follow-up of 10 weeks. The microbiota data were compared with that of the healthy donors. “

Review: Clostridium difficile and the microbiota – Anna M. Seekatz and Vincent B. Young – Journal of Clinical Investigation

“Both human and animal models have demonstrated the importance of the gut microbiota’s capability of providing colonization resistance against C. difficile.”

Vaginal microbiome

Primate vaginal microbiomes exhibit species specificity without universal Lactobacillus dominance – Suleyman Yildirim – ISME Journal

“We conducted comparative analyses of the primate vaginal microbiome using pyrosequencing of the 16S rRNA genes of a phylogenetically broad range of primates to test for factors affecting the diversity of primate vaginal ecosystems. … humans were distinct from other primates in both microbiome composition and diversity.“

Semen microbiome

The Semen Microbiome and Its Relationship with Local Immunology and Viral Load in HIV Infection – Cindy M. Liu – PLOS Pathogens

“HIV infection was associated with decreased semen microbiome diversity and richness, which were restored after six months of ART.”

Antibiotic perturbation and microbiome

Bacteria, phages and pigs: the effects of in-feed antibiotics on the microbiome at different gut locations – Torey Looft – ISME Journal

“In this study, we defined the lumenal and mucosal bacterial communities from the small intestine (ileum) and large intestine (cecum and colon) plus feces, and characterized the effects of in-feed antibiotics (chlortetracycline, sulfamethazine and penicillin (ASP250)) on these communities. “

Impact of Antibiotics on the Intestinal Microbiota and on the Treatment of Shiga-toxin-Producing Escherichia coli and Salmonella Infections – Szych, Jolanta – Current Pharmaceutical Design

“This review evaluates the current literature based on the impact of antibiotics on the intestinal microbiota and the critical role of intestinal bacteria in controlling infection and subsequent clinical disease caused by STEC and Salmonella, and the transmissibility of these important pathogens”

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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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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 10

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Hi all, just one post today, with everything combined. Bacterial vaginosis, daily rhythms  of marine bacteria, food microbiology, and The Picks.

Human vaginal microbiome

Role of Gardnerella vaginalis in the Pathogenesis of Bacterial Vaginosis: A Conceptual Model – Jane R. Schwebke – Journal of Infectious Diseases

“Our model suggests that BV is initiated by the sexual transmission of Gardnerella vaginalis, which has the appropriate virulence factors to adhere to host epithelium, create a biofilm community, and successfully compete with lactobacilli for dominance in the vaginal environment. “

Seawater microbiome

Multispecies dielMultispecies diel transcriptional oscillations in open ocean heterotrophic bacterial assemblages – Elizabeth A. Ottesen – Science, with an Editorial by E. Virginia Armbrust: “Taking the pulse of ocean microbes”

“As anticipated, the cyanobacterial transcriptome exhibited pronounced diel periodicity. Unexpectedly, several different heterotrophic bacterioplankton groups also displayed diel cycling in many of their gene transcripts. “

Screen Shot 2014-07-10 at 11.53.04 PMReview: Bacterial diversity and antibiotic resistance in water habitats: searching the links with the human microbiome – Ivone Vaz-Moreira – FEMS Microbiology Reviews

“In this review, the hypothesis that some bacteria may share different water compartments and be also hosted by humans is discussed based on the comparison of the bacterial diversity in different types of water and with the human-associated microbiome. “

Food microbiology

Cassava beerLocal domestication of lactic acid bacteria via cassava beer fermentation – Alese M. Colehour – PeerJ

“Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chicha batches using Illumina high-throughput sequencing. “

LobsterCharacterization of the dominant bacterial communities during storage of Norway lobster and Norway lobster tails (Nephrops norvegicus) based on 16S rDNA analysis by PCR-DGGE – Bekaert Karen – Food Microbiology

“To characterize as many bacterial species present as possible, we performed advanced molecular identification techniques (PCR-DGGE). The initial TVC of fresh Norway lobster meat was high (3.0 log cfu/g) as compared to fish.”

charquiEffect of autochthonous bacteriocin-producing Lactococcus lactis on bacterial population dynamics and growth of halotolerant bacteria in Brazilian charqui – Vanessa Biscola – Food Microbiology

“Charqui is a fermented, salted and sun-dried meat product, widely consumed in Brazil and exported to several countries. “

Microbes in the news

Using the gut microbiome to improve health – Mary MacVean – LA Times

“The “bistable” groups, the authors wrote, represent “tipping elements,” or components of the gut microbes that “exhibit alternative stable states linked to the overall ecosystem state and our physiology.” “

Science, Ethics and Publishing

Crack Down on Scientific Fraudsters – Adam Marcus and Ivan Oransky – New York Times

“Criminal charges against scientists who commit fraud are even more uncommon. In fact, according to a study published last year, “most investigators who engage in wrongdoing, even serious wrongdoing, continue to conduct research at their institutions.””

Dr. Bik’s Picks

Microplastics in the seas – Kara Lavender Law, Richard C. Thompson – Science

“Microplastics are likely the most numerically abundant items of plastic debris in the ocean today, and quantities will inevitably increase, in part because large, single plastic items ultimately degrade into millions of microplastic pieces. “

Uncontacted tribe in Brazil emerges from isolation – Heather Pringle – Science

“The meeting was Brazil’s first official contact with an isolated Amazonian tribe in 20 years. Anthropologists remain deeply concerned about the tribe’s future as it encounters novel diseases and resource-hungry outsiders. “

Polar BearsPolar Bears from Space: Assessing Satellite Imagery as a Tool to Track Arctic Wildlife – Seth Stapleton – PLOS ONE

“We examined satellite images of a small island in Foxe Basin, Canada, occupied by a high density of bears during the summer ice-free season. Bears were distinguished from other light-colored spots by comparing images collected on different dates. “

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Human microbiome, July 8

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Female urinary microbiome, stool microbiome and vaccine responses, and gut microbiome in ulcerative colitis patients.

Urinary tract

The Female Urinary Microbiome: a Comparison of Women with and without Urgency Urinary Incontinence – Meghan M. Pearce – mBio

“In this study, we used 16S rRNA gene sequencing to classify bacterial DNA and expanded quantitative urine culture (EQUC) techniques to isolate live bacteria in urine collected by using a transurethral catheter from women with UUI and, in comparison, a cohort without UUI. “

Gut microbiome

Stool Microbiota and Vaccine Responses of Infants – M. Nazmul Huda – Pediatrics

“Bifidobacterium predominance may enhance thymic development and responses to both oral and parenteral vaccines early in infancy”

Novel Gut-Based Pharmacology of Metformin in Patients with Type 2 Diabetes Mellitus – Antonella Napolitano – PLOS ONE

“Microbiota abundance of the phylum Firmicutes was positively correlated with changes in cholic acid and conjugates, while Bacteroidetes abundance was negatively correlated.”

This one was already published online in September 2013 but it came out in print this week : Commentary: Roseburia hominis: a novel guilty player in ulcerative colitis pathogenesis – Herbert Tilg – Gut

“In recent years evidence was accumulating that the gut microbiota and its manipulation might constitute one of those relevant ‘environmental’ factors. “

A decrease of the butyrate-producing species Roseburia hominis and Faecalibacterium prausnitzii defines dysbiosis in patients with ulcerative colitis – Kathleen Machiels – Gut

“The composition of the fecal microbiota of UC patients differs from that of healthy individuals: we found a reduction in R hominis and F prausnitzii, both well-known butyrate-producing bacteria of the Firmicutes phylum. “

Pregnancy and birth

Direct Evidence for the Presence of Human Milk Oligosaccharides in the Circulation of Breastfed Infants – Karen C. Goehring – PLOS ONE

“At least some ingested HMOs are absorbed intact into the circulation and excreted in the urine and their concentrations in these fluids correlate with levels of the corresponding mother’s milk”

Commentary: More than a gut feeling: predicting surgical necrotising enterocolitis – Jörn-Hendrik Weitkamp – Gut

“The paper by Sylvester et al 8 describes a new non-invasive approach of combining clinical data and selected urine peptide biomarkers to develop an algorithm to predict progression of suspected medical NEC to surgical disease. “

refers to: A novel urine peptide biomarker-based algorithm for the prognosis of necrotising enterocolitis in human infants – Karl G Sylvester – Gut

“Ensemble modelling combining clinical parameters with biomarker analysis dramatically improves our ability to identify the population at risk for developing progressive NEC.”

Animal models

Host Responses to the Pathogen Mycobacterium avium subsp. paratuberculosis and Beneficial Microbes Exhibit Host Sex Specificity – Enusha Karunasena – Applied and Environmental Microbiology

“The differences observed suggest that male and female gut tissues and microbiota respond to newly introduced microorganisms differently and that gut-associated microorganisms with host immune system responses and metabolic activity are supported by biology distinct to the host sex.”

General human microbiome

Phylogenetics and the human microbiome – Frederick A Matsen IV – Submitted to Systematic Biology

“In this paper I review the field and its methods from the perspective of a phylogeneticist, as well as describing current challenges for phylogenetics coming from this type of work.”

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