Microbiome digest, August 4, 2014

Relief in a pressing problem, microbes at high altitude, and microbiome in cystic fibrosis.

Human gut microbiome

So glad this one finally came out!  Structural changes in the gut microbiome of constipated patients – Lixin Zhu – Physiological Genomics

“A cross-sectional pilot study was performed to compare stool microbial composition of 8 constipated patients and 14 non-constipated controls using 16S rRNA gene pyrosequencing.”

Microbiota and diabetes: an evolving relationship – Herbert Tilg, Alexander R Moschen – Gut

“A further hint towards an association between microbiota and T2D has been derived from studies in pregnancy showing that major gut microbial shifts occurring during pregnancy affect host metabolism.”

Harnessing the Intestinal Microbiome for Optimal Therapeutic Immunomodulation – S. Viaud – Cancer Research

“gut commensals, through lipopolysaccharide and other bacterial components, switch the tumor microenvironment, in particular the redox equilibrium and the TNF production of intratumoral myeloid cells during therapies with platinum salts or intratumoral TLR9 agonists combined with systemic anti-IL10R Ab respectively.”

Specific genetic and microbial signature associated with paediatric ileal Crohn’s disease -Isobel Leake – Nature Reviews Gastroenterology & Hepatology

“An increase in DUOX2 expression was associated with an expansion of Proteobacteria across all forms of IBD, whereas downregulation of APOA1 expression in association with depletion of certain Firmicutes and Bacteroidetes taxa was found to be specific for Crohn’s disease.”

Skin and wounds microbiome

Next-Generation Sequencing: A Review of Technologies and Tools for Wound Microbiome Research – Brendan Hodkinson and Elizabeth Grice – Advances in Wound Care

“The purpose of this review is to outline the current platforms, their applications, and the steps necessary to undertake microbiome studies using next-generation sequencing.”

Human respiratory microbiome

Directly Sampling the Lung of a Young Child with Cystic Fibrosis Reveals Diverse Microbiota – Perry S Brown – Annals ATS

“After pathologic examination verified that this child’s lung tissue reflected CF lung disease, we used bacterial rRNA gene pyrosequencing and computational phylogenetic analysis to identify the microbiota in serial sections of the tissue.”

Respiratory Viruses and Bacteria among Pilgrims during the 2013 Hajj – Samir Benkouiten – Emerging Infectious Diseases

“One third (36.3%) of the participants had acquired S. pneumoniae during their stay. Our results confirm high acquisition rates of rhinovirus and S. pneumoniae in pilgrims and highlight the acquisition of coronavirus E229.”

Fish microbiome

The Colonization Dynamics of the Gut Microbiota in Tilapia Larvae – Christos Giatsis – PLOS ONE

“Our results showed that variation in gut microbiota between replicate tanks was not significantly higher than within tank variation, suggesting that there is no tank effect on water and gut microbiota. “

Soil microbiome

FEMS Microbiology Ecology has a special issue on Polar and Alpine Microbiology with many papers on microbiomes of ice and soil. Here is the Editorial:
Polar and alpine microbiology in a changing world – John C. Priscu – FEMS Microbiology Ecology

“By virtue of their relatively rapid growth rates and metabolic diversity, we can expect microorganisms to be the first responders to fluctuating climatic conditions.”

Altitudinal Distribution Patterns of Soil Bacterial and Archaeal Communities Along Mt. Shegyla on the Tibetan Plateau – Jun-Tao Wang – Microbial Ecology

“Our results found that the ratio of bacterial to archaeal 16S rRNA gene abundance was negatively related with elevation.”

Water microbiome

Satellite remote sensing data can be used to model marine microbial metabolite turnover – Peter E Larsen – ISME Journal

“We extrapolated marine surface microbial community structure and metabolic potential from 72 16S rRNA amplicon and 8 metagenomic observations using remotely sensed environmental parameters”

Microbial Ecology

Changes in community assembly may shift the relationship between biodiversity and ecosystem function – Joseph E. Knelman and Diana R. Nemergut – Frontiers Microbiology

“Can differences in community assembly alter the relationship between biodiversity and ecosystem function?”

Probiotics

Lactobacillus rhamnosus GG suspected infection in a newborn with intrauterine growth restriction – I. Sadowska-Krawczenko – Beneficial Microbes

“Genotyping with the rep-PCR and AFLP methods confirmed the 100% genetic similarity for both the strain isolated from patient blood and the probiotic product.”

Can Eating Probiotic Yogurt Help Lower Your High Blood Pressure? – Susmita Baral – Wall St Cheat Sheet

“Now, a new study (published Monday in the journal Hypertension) has found another added benefit of probiotics — it may reduce high blood pressure.”

Microbes in the News

Your garden hose: a potential health risk due to Legionella spp. growth facilitated by free-living amoebae – Jacqueline Marie Thomas – Environmental Science & Technology

“Here we present data on FLA and Legionella spp. detected in water and biofilm of two garden hose types over 18 months. “

Truth about your toothbrush – Anne Agbaje – Bussiness Day Online

“You don’t store your plates and glasses by the toilet, so why would you want to place your toothbrush there?” McCombs says. “It’s just common sense to store your toothbrush as far away from the toilet as possible.”

Metabolomics

Fecal volatile organic compounds: a novel, cheaper method of diagnosing inflammatory bowel disease? – Chris SJ Probert – Expert Review of Clinical Immunology

“…this article will focus specifically on the fecal VOC metabolome and its potential role in identifying a novel diagnostic method for IBD.”

Review: Emerging mass spectrometry techniques for the direct analysis of microbial colonies – Jinshu Fang, Pieter C Dorrestein – Current Opinion in Microbiology

“In this review/perspective, we illustrate the emerging mass spectrometry methodologies that enable the interrogation of specialized metabolites directly from microbial colonies.”

Techniques

Improved performance of the PacBio SMRT technology for 16S rDNA sequencing – Jennifer J. Mosher – Journal of Microbiological Methods

“With accurate read lengths of > 1400 base pairs, the PacBio system opens up the possibility of identifying microorganisms to the species level in environmental samples.”

 

Bik’s Picks

The Secret to a Tattoo’s Permanence: The Immune System – Olga Khazan – The Atlantic

“We rarely stop and think about the science of tattoos. In fact, some people don’t even stop and think before getting tattooed.”

 

Mathematical equation to predict happiness: Doesn’t depend on how well things go, but on whether things are better than expected – Science Daily

The happiness of over 18,000 people worldwide has been predicted by a mathematical equation, with results showing that moment-to-moment happiness reflects not just how well things are going, but whether things are going better than expected.”

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Human microbiome, June 19

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

Oral microbiome

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

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

Gut microbiome

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

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

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

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

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

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

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

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

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

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

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

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

Respiratory microbiome

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

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

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

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

Skin and wounds microbiology

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

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

Press coverage:

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

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

Human microbiome in the news

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

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

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

“During this webinar, the speakers will:

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

Bacterial detection in blood and other sites

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

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

Animal models of microbiota

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

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

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