Microbiome digest, October 8, 2014

Blogging from our yearly retreat in Santa Cruz, California: Rethinking Enterotypes, Wolbachia phylogenomics,  hydrothermal vents, and the influence of salamanders on soil microbiome.

Human Microbiome General

Genes & cells: Body microbes make useful molecules: Human microbiome produces thousands of drug candidates – Tina Hesman Saey – Science News

Human Gut Microbiome

Rethinking “Enterotypes” – Dan Knights – Cell Host and Microbe

“However, as discussed here, several different methods of collapsing enterotype variation into a few discrete clusters suggest that enterotype distribution is continuous and can vary widely within an individual.”

Fecal Bacterial Community Changes Associated with Isoflavone Metabolites in Postmenopausal Women after Soy Bar Consumption – Cindy H. Nakatsu – PLOS ONE

“Using DGGE profiles of PCR amplified 16S rRNA genes (V3 region) to compare microbial communities in fecal samples collected one week before and one week during soy supplementation revealed significant differences (ANOSIM p<0.03) before and after soy supplementation in all subjects. “

Insect microbiome

Phylogenomic analyses uncover origin and spread of the Wolbachia pandemic – Michael Gerth  – Nature Communications

“Here we present the first comprehensive phylogenomic analysis of Wolbachia supergroup relationships based on new whole-genome-shotgun data.”

Coral microbiome

Comparing Bacterial Community Composition of Healthy and Dark Spot-Affected Siderastrea siderea in Florida and the Caribbean – Christina A. Kellogg – PLOS ONE

“Microbial-community DNA was extracted from coral samples (mucus, tissue, and skeleton), amplified using bacterial-specific primers, and applied to PhyloChip G3 microarrays to examine the bacterial diversity associated with this coral. “

Soil Microbiome

Summer temperature increase has distinct effects on the ectomycorrhizal fungal communities of moist tussock and dry tundra in Arctic Alaska – Luis N. Morgado – Global Change Biology

“We used Ion Torrent sequencing of the rDNA internal transcribed spacer 2 (ITS2) region to compare ECM fungal communities in plots with and without long-term experimental warming in both dry and moist tussock tundra.”

A metagenomics-based approach to the top-down effect on the detritivore food web: a salamanders influence on fungal communities within a deciduous forest – Donald M. Walker – Ecology and Evolution

“From each sample, DNA was extracted, fungal-specific amplification performed, and 454 pyrosequencing was used to sequence the nuclear ribosomal internal transcribed spacer (ITS2) region and partial ribosomal large subunit (LSU).”

Water microbiome

Evolutionary Strategies of Viruses, Bacteria and Archaea in Hydrothermal Vent Ecosystems Revealed through Metagenomics – Rika E Anderson – PLOS ONE

“Here, we explore the evolutionary strategies of both microorganisms and viruses in hydrothermal systems through comparative analysis of a cellular and viral metagenome, “

Metabolomics

Discovery and Characterization of Gut Microbiota Decarboxylases that Can Produce the Neurotransmitter Tryptamine – Brianna B. Williams – -Cell Host and Microbe

“Using a combination of genetics, biochemistry, and crystallography, we identify and characterize two phylogenetically distinct enzymes found in the human microbiome that decarboxylate tryptophan to form the β-arylamine neurotransmitter

Techniques

Selective Microbial Genomic DNA Isolation Using Restriction Endonucleases – Helen E. Barnes – PLOS ONE

“Using synthetic genome mixtures, we demonstrate 80% recovery of Escherichia coli genomic DNA even when only femtogram quantities are spiked into 10 µg of human DNA background.”

 More Microbiology

Pseudomonas aeruginosa eradicates Staphylococcus aureus by manipulating the host immunity – Erwan Pernet – Nature Communications

“Our results indicate that a bacterium can eradicate another bacterium by manipulating the host immunity.”

Preparation and evaluation of low-calorie functional ice cream containing inulin, lactulose and Bifidobacterium lactis  – Majid Hashemi- International Journal of Dairy Technology

“This study was aimed to investigate the effects of replacing 5% fat and sugar by inulin and lactulose, respectively, on the survival of Bifidobacterium lactis and physicochemical and sensorial characteristics of the ice cream. “

Microbes in the News

Second Genome, Mayo Clinic team up to explore the microbiome – Stephanie M. Lee – SF Gate

“Second Genome will identify up to eight conditions in which the microbiome potentially plays a role, and the Mayo Clinic will provide human clinical samples for patients with those diseases.”

 Oral health affects overall health – PhillyTrib

“The evidence shows that an infection from periodontitis, or gum disease, can put you at risk for other serious conditions like heart disease, stroke and more.”

Safety Bees: Bacteria From Bees Used To Fight Infections – The Ledger

 “A group of 13 lactic-acid bacteria found in fresh honey from the honey stomach of bees could be the key to bringing an old folk remedy into modern science”

Bik’s Picks  

How dinosaurs divided their meals at the Jurassic dinner table – Science Daily

“How the largest animals to have ever walked on Earth fed, and how this allowed them to live alongside one another in prehistoric ecosystems, is the subject of new research.”

Imitation, Genetic Lineages, and Time Influenced the Morphological Evolution of the Violin – Daniel H. Chitwood – PLOS ONE

“Here, I provide an analysis of morphological evolution in the violin family, sampling the body shapes of over 9,000 instruments over 400 years of history.”

Cat Watch 2014: What’s it like being a cat? – BBC

“Cats are at a crucial point in their evolutionary journey as they transform from solitary hunters to domestic pets, a study by the BBC and the Royal Veterinary College has revealed.”
[hr]

Human microbiome digest, September 29, 2014

[hr]

Smoking and the subgingival ecosystem, inflammatory bowel diseases, iron in the gut, and metabolism of acetaminophen.

Pregnancy and birth

External influence of early childhood establishment of gut microbiota and subsequent health implications – Peris M. Munyaka – Frontiers in Pediatrics

“Early exposures impacting the intestinal microbiota are associated with the development of childhood diseases that may persist to adulthood”

Human oral microbiome

* 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.”

Human gut microbiome

Functional Impacts of the Intestinal Microbiome in the Pathogenesis of Inflammatory Bowel Disease – Jennifer Li – Inflammatory Bowel Diseases

“We highlight functional roles of specific bacterial groups in the development and management of IBD. “

Nutritional iron turned inside out: intestinal stress from a gut microbial perspective – Guus A.M. Kortman – FEMS Microbiology Reviews

“This review covers the multifaceted aspects of nutritional iron stress with respect to growth, composition, metabolism and pathogenicity of the gut microbiota in relation to human health.”

Animal models of microbiome research

The role of intestinal microbiota in murine models of acetaminophen-induced hepatotoxicity – Lucia A Possamai – Liver International

“A urinary metabolic profile was obtained using 1H-NMR. Baseline hepatic glutathione content and CYP2E1 expression were quantified.”

Dietary Xylo-oligosaccharide stimulates intestinal bifidobacteria and lactobacilli but has limited effect on intestinal integrity in rats – Ellen Gerd Christensen – BMC Research Notes

“Changes in faecal and caecal bacterial composition determined by 16S rRNA gene sequencing and quantitative PCR for selected bacterial groups revealed that the overall bacterial composition did not differ markedly“

[hr]

Human microbiome digest, September 15, 2014

MicrobiomeDigest is back! Lots of new papers came out in my 2-week hiatus, so here we go (more tomorrow):

General (Human) Microbiota

Editorial for Special Issue: Insights into Molecular Mechanisms of Microbiota – Eric C. Martens, Justin L. Sonnenburg, David A. Relman – Journal of Molecular Biology

“Understanding the molecular mechanisms that underlie these processes has been a goal for decades, but while recent technological advances have greatly expanded our descriptive view of these ecosystems, our knowledge of underlying functions and mechanisms has lagged. “

A Systematic Analysis of Biosynthetic Gene Clusters in the Human Microbiome Reveals a Common Family of Antibiotics – Mohamed S. Donia – Cell

“we identified 3,118 small-molecule biosynthetic gene clusters (BGCs) in genomes of human-associated bacteria and studied their representation in 752 metagenomic samples from the NIH Human Microbiome Project.”

See also:

Mining for Antibiotics, Right Under Our Noses – Carl Zimmer – New York Times

The Integrative Human Microbiome Project: Dynamic Analysis of Microbiome-Host Omics Profiles during Periods of Human Health and Disease – iHMP Consortium – Cell Host & Microbe

“Here we describe the three models of microbiome-associated human conditions, on the dynamics of preterm birth, inflammatory bowel disease, and type 2 diabetes”

Microbiome in pregnancy and birth
Review: Diet and host–microbial crosstalk in postnatal intestinal immune homeostasis – Nitya Jain & W. Allan Walker – Nature Reviews Gastroenterology & Hepatology

“In this Review, we discuss the current state of knowledge regarding early-life nutrition, its effects on the microbiota and the consequences of diet-induced perturbation of the structure of the microbial community on mucosal immunity and disease susceptibility.”

The early use of appropriate prophylactic antibiotics in susceptible women for the prevention of preterm birth of infectious etiology – Jan Stener Joergensen – Expert Opinion on Pharmacotherapy

“a focused systematic review/meta-analysis, which targeted the use of clindamycin before 22 weeks gestation, in women with objective evidence of abnormal genital tract flora, demonstrated that clindamycin produced a significant decrease in late miscarriage and preterm birth.”

Mucosa-Associated Bacterial Diversity in Necrotizing Enterocolitis – Rachel Brower-Sinning – PLOS ONE

26 intestinal samples were resected from 19 infants, including 16 NEC samples and 10 non-NEC samples. Bacterial 16S rRNA gene sequences were amplified and sequenced. “

Oral human microbiome

The presence of cariogenic and periodontal pathogens in the oral cavity of one-year-old
infants delivered pre-term with very low birthweights: a case control study – Vlasta Merglova – BMC Oral Health

“At 12 months of age, both groups of infants were examined, and unstimulated saliva samples from the dorsum of the tongue and dental plaque samples were collected.”

Frequent detection of Streptococcus tigurinus in the human oral microbial flora by a specific 16S rRNA gene real-time TaqMan PCR – Andrea Zbinden – BMC Microbiology

“Although S. tigurinus was a frequently detected species of the human oral microbial flora, it was not associated with periodontal disease. “

Oral Microbiome Link to Neurodegeneration in Glaucoma – Konstantin Astafurov – PLOS ONE

“Mouthwash specimens from patients with glaucoma and control subjects were analyzed for the amount of bacteria”

Bacterial community composition of chronic periodontitis and novel oral sampling sites for detecting disease indicators  – Vaia Galimanas – Microbiome

“Using SubG, SupG, and tongue plaque DNA from 11 healthy and 13 diseased subjects, we sequenced V3 regions (approximately 200 bases) of the 16S rRNA gene using Illumina sequencing.”

Human gut microbiome

TLR5-Mediated Sensing of Gut Microbiota Is Necessary for Antibody Responses to Seasonal Influenza Vaccination – Jason Z. Oh – Immunity

“TLR5-mediated sensing of the microbiota also impacted antibody responses to the inactivated polio vaccine, but not to adjuvanted vaccines or the live-attenuated yellow fever vaccine.”

Review: Nutritional iron turned inside out: intestinal stress from a gut microbial
perspective – Guus A.M. Kortman – FEMS Microbiology Reviews

“This review covers the multifaceted aspects of nutritional iron stress with respect to growth, composition, metabolism and pathogenicity of the gut microbiota in relation to human health.”

Review: Host–microbe interactions shaping the gastrointestinal environment – Gerard E. Kaiko, Thaddeus S. Stappenbeck – Trends in Immunology

“Here we review emerging concepts of how microbial metabolic processes control commensal composition, invading pathogens, immune activation, and intestinal barrier function. “

The microbial eukaryote Blastocystis is a prevalent and diverse member of the healthy human gut microbiota – Pauline D. Scanlan – FEMS Microbiology Ecology

“Here, we survey the prevalence, genetic diversity and temporal stability of Blastocystis in a group of healthy adults (n = 105) using a sensitive PCR assay.”

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 hypervariable region within the ITS suitable for precise taxonomic identification of all 48 so far recognized members of the Bifidobacterium genus.”

Alzheimer’s disease and the microbiome – James M. Hill – Alzheimer’s & Dementia

“In these preliminary studies we evaluated the effects of the anti-amyloid, anti-oxidant, anti-inflammatory flavonoid quercetin on growth inhibition of the HM-representative Bacteroides galacturonicus (ATCC 43244).”

Complete Suppression of the Gut Microbiome Prevents Acute Graft-Versus-Host Disease following Allogeneic Bone Marrow Transplantation  – Jaak M. Vossen – PLOS ONE

“All patients received T-cell replete marrow from human leukocyte antigens (HLA) matched sibling donors under identical transplantation conditions.”

Associations of the Fecal Microbiome With Urinary Estrogens and Estrogen Metabolites in Postmenopausal Women – Barbara J. Fuhrman – Journal of Clinical Endocrinology & Metabolism

“Our data suggest that women with a more diverse gut microbiome exhibit an elevated urinary ratio of hydroxylated estrogen metabolites to parent estrogen. “

Alterations of the human gut microbiome in liver cirrhosis – Nan Qin – Nature

“Here we characterize the gut microbiome in liver cirrhosis by comparing 98 patients and 83 healthy control individuals. “

Altered intestinal microbiota and blood T cell phenotype are shared by patients with Crohn’s disease and their unaffected siblings – Charlotte R Hedin – Gut

“Faecal microbiology was analysed by quantitative PCR targeting 16S ribosomal RNA, FC by ELISA, blood T cell phenotype by flow cytometry and IP by differential lactulose-rhamnose absorption in 22 patients with inactive CD, 21 of their healthy siblings and 25 controls.”

Detection of bacterial DNA in lymph nodes of Crohn’s disease patients using high throughput sequencing – Claire L O’Brien – Gut

“Universal primers targeting V1–V3 regions of bacterial 16S rRNA genes were used to amplify bacterial DNA and amplicons sequenced using high throughput sequencing. “

Cultivation-based multiplex phenotyping of human gut microbiota allows targeted recovery of previously uncultured bacteria – Elizabeth A. Rettedal – Nature Communications

“Here, we show that carefully designed conditions enable cultivation of a representative proportion of human gut bacteria, enabling rapid multiplex phenotypic profiling. “

Animal models of human microbiome research

Innate lymphoid cells regulate intestinal epithelial cell glycosylation – Yoshiyuki Goto – Science

“Here, we show that type 3 innate lymphoid cells (ILC3) induced intestinal epithelial Fut2 expression and fucosylation in mice. “

Effect of Metformin on Metabolic Improvement and Gut Microbiota – Heetae Lee and GwangPyo Ko – Applied and Environmental Microbiology

“In this study, the composition of the gut microbiota was investigated using a mouse model of high-fat-diet (HFD)-induced obesity with and without metformin treatment. “

Microbiota modulate transcription in the intestinal epithelium without remodeling the accessible chromatin landscape – J. Gray Camp – Genome Research

“We profiled transcriptome and accessible chromatin landscapes in intestinal epithelial cells (IECs) from mice reared in the presence or absence of microbiota.”

Host adaptive immunity alters gut microbiota – Husen Zhang – ISME Journal

“Here we investigated the role of adaptive immunity on the mouse distal gut microbial composition by sequencing 16 S rRNA genes from microbiota of immunodeficient Rag1−/− mice, versus wild-type mice, under the same housing environment.”

[hr]

Human microbiome digest, August 19, 2014

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).

[hr]

Bifidobacterium longum and Bifidobacterium breve isolates from preterm and full term neonates: Comparison of cell surface properties

Screen Shot 2014-07-18 at 2.31.12 PMBifidobacterium longum and Bifidobacterium breve isolates from preterm and full term neonates: Comparison of cell surface properties
Valérie Andriantsoanirina – Anaerobe

“Our results suggest the existence of variations in bifidobacteria membrane structure and/or composition that may reflect adaptation of these bacteria to the intestinal environment of either preterm or full term neonates. “