Human microbiome digest, September 16, 2014

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, June 16

A guide to your poop and more serious papers about oral, vaginal microbiomes and bacteria detection in joint fluids.

Oral microbiome

Screen Shot 2014-06-16 at 11.19.50 PMBacteria choose to fight and flee (commentary on a recent PNAS paper by Stacy et al. )- Christina Tobin Kåhrström – Nature Reviews Microbiology

“Together, these data suggest an elegant mechanism by which A. actinomycetemcomitans uses catalase to enzymatically ‘fight’ H2O2 and dispersin B to ‘flee’ from the close vicinity of S. gordonii, where H2O2 levels are highest, to a location where access to L-lactate is still possible. “

Oral challengesFornitersChallenges in the culture-independent analysis of oral and respiratory samples from intubated patients – Vladimir Lazarevic – Front. Cell. Infect. Microbiol.

“We explored the bacterial community diversity of the microbiota from oral and respiratory samples of intubated patients hospitalized in the intensive care unit and we discuss the technical challenges that may arise while using culture-independent approaches to study these types of samples.”

Vaginal microbiome

Ashok VagInfluence of the tryptophan-indole-IFNγ axis on human genital Chlamydia trachomatis infection: role of vaginal co-infections – Ashok Aiyar – Front. Cell. Infect. Microbiol.

“In this review, we discuss the natural history of genital chlamydial infections, morphological and molecular changes imposed by IFNγ on Chlamydia, and finally, the microenvironmental conditions associated with vaginal co-infections that can ameliorate the effects of IFNγ on C. trachomatis.”

Gut microbiome

ToiletThe Not-So-Gross Guide to Your Poop – Laura Barcella – Refinery29

“So, what is your excrement trying to tell you? Read on for clues about how to decipher your bowel movements.”

Bacteria detection in otherwise sterile sites

Screen Shot 2014-06-16 at 11.24.38 PMRapid isolation and diagnosis of live bacteria from human joint fluids by using an integrated microfluidic system – Wen-Hsin Chang – Lab on a Chip

 

“…an integrated microfluidic system capable of detecting live bacteria from clinical PJI samples within 55 minutes is developed in this study. This system employs an ethidium monoazide (EMA)-based assay and a PCR with universal bacterial primers and probes to isolate and detect only the live bacteria that commonly cause PJI. “

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Human microbiomes, June 5

Today we have some commentaries on recent papers about microbiotas in malnutrition or on placentas, and new papers about oral bacteria in the bloodstream, helminths, and coincidental killers.

Oral microbiome

Screen Shot 2014-06-05 at 7.59.36 PMDissemination of Periodontal Pathogens in the Bloodstream after Periodontal Procedures: A Systematic Review – Anna Carolina Ratto Tempestini Horliana – PLOS ONE

“MEDLINE, EMBASE and LILACS databases were searched in duplicate through August, 2013 without language restriction. Observational studies were included if blood samples were collected before, during or after periodontal procedures of patients with periodontitis”

Screen Shot 2014-06-05 at 7.56.12 PMThe Emerging Landscape of Salivary Diagnostics – Yong Zhang- OHDM – Omics Online

“Here we review recent developments in salivary diagnostics that have been accomplished using salivaomics, the mechanisms of saliva diagnostics, as well as the translational and clinical application of saliva biomarkers”

Gut microbiome

Screen Shot 2014-06-05 at 7.57.14 PMInfection and Co-infection with Helminths and Plasmodium among School Children in Côte d’Ivoire: Results from a National Cross-Sectional Survey – Richard B. Yapi – PLOS Neglected Tropical Diseases

“We carried out the first national survey on parasitic worm and Plasmodium infection among children in 92 schools all over Côte d’Ivoire. Questionnaires were administered to determine the children’s socioeconomic status and infection-related risk factors. We found an overall prevalence of Plasmodium infection of 63.3%.”

ColonSome Antibiotics May Slightly Increase Colon Cancer Risk – Bahar Gholipour – LiveScience

“The researchers compared the amount of antibiotics the patients had taken at least six months before being diagnosed with cancer, to the amount of antibiotics taken by a group of about 86,000 healthy people.”

Screen Shot 2014-06-05 at 10.07.58 AMWhy Can’t Once-Malnourished Children “Catch Up”? Answer May Lie in Gut – Karen Weintraub – National Geographic

“There’s something lacking in our current approach to treatment,” said Gordon, who suspects the children may need to eat therapeutic foods for longer and/or get supplements of probiotics, or beneficial microorganisms, to catch up. “We need to think of food as interacting with this microbial organ.”

Screen Shot 2014-06-05 at 8.03.26 PMSevere hunger can have lasting effects for gut health, study finds – MedicalXPress

“Nutrition therapy has saved the lives of millions of malnourished infants, but may not restore an imbalance in gut bacteria that is key to long-term health and vitality, researchers said Wednesday.”

Pregnancy and birth

Screen Shot 2014-06-05 at 8.05.15 PMGearing up for a closer look at the human placenta – Jocelyn Kaiser – Science

“A placenta sustained you and every person ever born for 9 months, serving as your lungs and kidneys and pumping out hormones while you developed in the womb. Problems with this disk-shaped mass of tissue can contribute to everything from preterm births to diseases of middle age. Yet when a baby is born, hospitals usually throw the placenta away.”

Screen Shot 2014-06-05 at 9.57.32 AMMicrobirth: Why ‘Seeding Baby’s Microbiome’ Needs to Be on Every Birth Plan – Toni Harman – HuffingtonPost

“The latest scientific research is now starting to indicate that if the baby is not properly seeded with the mother’s own bacteria at birth, then the baby’s microbiome, in the words of Rodney R Dietert, Professor of Immunotoxicology at Cornell University, is left “incomplete”.”

General human microbiome

Screen Shot 2014-06-05 at 8.07.51 PMCoincidental killers – We assume that microbes evolved to attack humans when actually we are just civilian casualties in a much older war – Ed Yong – Aeon Magazine

“And some supposedly pathogenic bacteria were often common parts of the environment. ‘These organisms become accidental pathogens,’ says the microbiologist Arturo Casadevall from Yeshiva University in New York. ‘They’ll still be there even if you remove all the animals from the planet. And yet, evolution selected for just the right combination of traits to cause disease in humans.’”

Screen Shot 2014-06-05 at 8.12.08 PMSilicon Valley’s Top Ten Tech Trends – Jacqueline Vanacek – Forbes
Trend #7: Data-driven healthcare (from your gut).

The combination of personal health and fitness data, genomics, and even microbiomics will drive healthcare choices from real outcomes and individual probabilities. And since the bacteria in our digestive tracks has greater influence on our health than previously known, we really are what we eat!

Microbiome and Bioinformatics

Screen Shot 2014-06-05 at 8.11.20 PMBOTUX: Bayesian–like operational taxonomic unit examiner – Vishal N. Koparde – International Journal of Computational Biology and Drug Design

“Bayesian–like operational taxonomic unit examiner (BOTUX) is a new tool for the classification of 16S rRNA gene sequences into operational taxonomic units (OTUs) that addresses the problem of overestimation caused by errors introduced during PCR amplification and DNA sequencing steps”

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Human microbiome digest, June 3, 2014

Antimicrobial proteins in saliva, Lactobacillus spp and preterm birth, and probiotics. It’s been a long day, so no pictures today.

Oral microbiome

Salivary antimicrobial proteins associate with age related changes in streptococcal composition in dental plaque – Jennifer Malcolm – Molecular Oral Microbiology

“Dental plaque and saliva were collected from 57 children aged 12-24 months at baseline, of whom 23 children were followed-up at three-years of age. At each time, saliva was assessed for LL37, HNPs 1-3, calprotectin, lactoferrin, salivary IgA, total plaque bacteria and Streptococcus mutans.”

Pregnancy and birth

Characterisation of the vaginal Lactobacillus microbiota associated with preterm delivery – Ljubomir Petricevic – Nature Scientific Reports

“This study suggests that dominating L. iners alone detected in vaginal smears of healthy women in early pregnancy might be associated with preterm delivery”

Development of the preterm gut microbiota in infants at risk of necrotising enterocolitis and sepsis – Christopher Stewart – Doctoral thesis, Northumbria University

Intestinal Microbial Community Profiles of a Newborn Preterm Infant Using Pyrosequencing Analysis: Pilot Study (in Korean)- Jong-Geol Kim – Neonatal Medicine

“The bacterial community in the newborn’s meconium was quite similar to that in the AF, which was dominated by Sphingomonas (45.2%). “

Gut microbiome

Relating the metatranscriptome and metagenome of the human gut – Eric A. Franzosa with Curtis Huttenhower – PNAS

“Measurements of microbial species, gene, and gene transcript composition within self-collected samples were consistent across sampling methods.”

Defining the diversity of microbial eukaryotic communities in the mammalian gut within the context of environmental eukaryotic diversity – Laura W. Parfrey – Frontiers in Microbiology

“We show that adults from non-western populations harbor a diverse community of protists, and diversity in the human gut is comparable to that in other mammals. “

General human microbiome

Culturing For Cures – UCSF Scientists Explore the Bacterial Communities that Live In and On Our Bodies to Find Treatments for Disease – Claire Conway – UCSF News

“Scientists are hard at work trying to leverage the extraordinary healing powers of the microbiome, mining it for treatments of a variety of conditions, including asthma, irritable bowel syndrome and obesity.”

Probiotics

Autoinducer-2 Plays a Crucial Role in Gut Colonization and Probiotic Functionality of Bifidobacterium breve UCC2003 – Steven E. A. Christiaen – PLOS ONE

“we conclude that bifidobacteria operate a LuxS-mediated system for gut colonization and pathogen protection that is correlated with iron acquisition”

Urinary metabolomic fingerprinting after consumption of a probiotic strain in women with mastitis – Rosa Vázquez-Fresno – Pharmacological Research

“The application of NMR-based metabolomics enabled the identification of the overall effects of probiotic consumption among women suffering from mastitis and highlighted the potential of this approach in evaluating the outcomes of probiotics consumption.”

Animal models of gut microbiota

Effects of subchronic exposure of silver nanoparticles on intestinal microbiota and gut-associated immune responses in the ileum of Sprague-Dawley rats – Katherine Williams – Nanotoxicology

“This study evaluated changes in the populations of intestinal-microbiota and intestinal-mucosal gene expression in Sprague-Dawley rats (both male and female) that were gavaged orally with discrete sizes of AgNP (10, 75 and 110 nm) and silver acetate.”

Metabolomics

Oral Abstract: The high colon cancer risk in African Americans can be reduced by dietary modification – Stephen O’Keefe – Cancer & Metabolism

“dietary switch between these two populations produces reciprocal changes in the microbiome, metabolome, and mucosal biomarkers of risk within 2 weeks”

Strategies in Discovery Metabolomics – Kate Marusina – GenEngNews

Microbiome conferences

2nd World Congress on Targeting Microbiota – Institut Pasteur, Paris, France – October 16-17, 2014

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More microbiology and science, June 2, 2014

Dengue and humidity, bacteria from Mars, sequencing, and aspartame.

Dengue

Microbes in Space

Sequencing and bioinformatics

Chromosome organization

Arsenic metabolism

Dr. Bik’s Picks

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