Category Archives: Human gut

Human microbiome, July 29

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Papillomaviruses in human skin, gastric mucosa in cancer patients, breast milk metabolome, microbiome of a human family, and more.

Skin microbiome

Deep sequencing extends the diversity of human papillomaviruses in human skin –
Davit Bzhalava – Nature Scientific Reports

“This deeper sequencing without prior PCR of a pool of 142 whole genome amplified skin lesions identified 23 known HPV types, 3 novel putative HPV types and 4 non-HPV viruses.”

Gastric microbiome

Differences in Gastric Mucosal Microbiota Profiling in Patients with Chronic Gastritis, Intestinal Metaplasia, and Gastric Cancer Using Pyrosequencing Methods – Chang Soo Eun – Helicobacter

“Gastric mucosal biopsy samples were collected from 31 patients during endoscopy. After the extraction of genomic DNA, variable region V5 of the 16S rRNA gene was amplified. PCR products were sequenced using 454 high-throughput sequencer. “

Pregnancy and Birth

Breast milk metabolome characterization in a single phase extraction, multiplatform analytical approach – Alma Villaseñor – Analytical Chemistry

“We conducted this single-phase extraction procedure on a representative pool of BM, and characterized the metabolic composition using LC-QTOF-MS and GC-Q-MS for polar and lipidic metabolites. “

Effects of Bifidobacterial Supplementation to Pregnant Women and Infants in the
Prevention of Allergy Development in Infants and on Fecal Microbiota [PDF]- Tadao Enomoto – Allergology International

“Effects of Bifidobacterial Supplementation to Pregnant Women and Infants in the Prevention of Allergy Development in Infants and on Fecal Microbiota”

Gut microbiome
The dynamics of a family’s gut microbiota reveal variations on a theme – Patrick D Schloss – Microbiome

“Here we study a chronosequence of the gut microbiota found in eight individuals from a family consisting of two parents and six children ranging in age from two months to ten years old.”

Identifying Keystone Species in the Human Gut Microbiome from Metagenomic Timeseries Using Sparse Linear Regression – Charles K. Fisher – PLOS ONE

“Here we introduce an approach, Learning Interactions from MIcrobial Time Series (LIMITS), that overcomes these obstacles. LIMITS uses sparse linear regression with boostrap aggregation to infer a discrete-time Lotka-Volterra model for microbial dynamics. “

Antivirulence Activity of the Human Gut Metabolome – L. Caetano M. Antunes – mBio

“We found that a secreted molecule produced by clostridia acts as a strong repressor of Salmonella virulence, obliterating expression of the Salmonella pathogenicity island 1 as well as host cell invasion.”

 Metagenomic Identification of a Novel Salt Tolerance Gene from the Human Gut Microbiome Which Encodes a Membrane Protein with Homology to a brp/blh-Family β-Carotene 15,15′-Monooxygenase – Eamonn P. Culligan – PLOS ONE

“Herein, we report the identification and characterisation of a novel stress tolerance gene from the human gut metagenome. The locus, assigned brpA, encodes a membrane protein with homology to a brp/blh-family β-carotene monooxygenase. “

Review: Archaea and the human gut: New beginning of an old story [DOC]- Gaci N – World Journal of Gastroenterology

“Here we provide an updated census of the archaeal diversity associated to human GIT and their possible role in the gut physiology and health.”

 

Animal models of human microbiome and disease

Maternal high protein or prebiotic fiber diets affect maternal milk composition and gut microbiota in rat dams and their offspring – Megan C. Hallam – Obesity

“Fecal microbiota was analyzed in dams at parturition and 2 weeks post-partum and in offspring at 5 and 22 weeks along with cecal digesta at termination.”

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Human microbiome, July 28

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Oral microbes balancing their budgets, bacteria see blue, why Obama likes to fist bump, Gardnerella, and oxygen gradients in the gut.

Oral microbiome

Bioinformatic investigation of the cost management strategies of five oral microbes – Keith J. Cross – Molecular Oral Microbiology

“For Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Prevotella intermedia, and Streptococcus sanguinis, the outer membrane/extracellular proteins are made up of a much larger percentage of lower average mass amino acids whereas cytoplasmic proteins are made up of a larger proportion of higher average mass amino acid residues.”

Code blue: Acinetobacter baumannii, a nosocomial pathogen with a role in the oral cavity – Ashley M. Richards – Molecular Oral Microbiology

“A. baumannii can sense blue light through a blue-light sensing using flavin (BLUF) domain protein, BlsA. The resulting conformational change in BlsA leads to changes in gene expression, including virulence genes.”

Skin microbiome

Study: Fist bumps are less germy than handshakes – Kim Painter – USA Today

“Whitworth and a colleague systematically tested the three greetings for a study published Monday in the American Journal of Infection Control.” (article not available yet – MD).

Vaginal microbiome

Gardnerella vaginalis Outcompetes 29 Other Bacterial Species Isolated From Patients With Bacterial Vaginosis, Using in an In Vitro Biofilm Formation Model – Patrícia Alvesa – Journal of Infectious Diseases

“Here, we isolated 30 BV-associated species and characterized their virulence, using an in vitro biofilm formation model. “

Long-term Effect of Depot Medroxyprogesterone Acetate on Vaginal Microbiota, Epithelial Thickness and HIV Target Cells – Caroline M. Mitchell – Journal of Infectious Diseases

“Vaginal microbiota of women using DMPA for up to 2 years were cultured. Mucosal immune cell populations were measured by immunohistological staining.”

Gut microbiome

Correlation Between Intraluminal Oxygen Gradient and Radial Partitioning of Intestinal Microbiota in Humans and Mice – L. Albenberg – Gastroenterology

“In humans, 16S rRNA gene analyses revealed an increased proportion of oxygen-tolerant organisms of the Proteobacteria and Actinobacteria phyla associated with the rectal mucosa, compared with the feces, indicating an effect of oxygenation on the microbiota. “

Patients with cystic fibrosis have a high carriage rate of non-toxigenic Clostridium difficile – M. P. Bauer – Clinical Microbiology and Infection

“In this case-control study, we found more carriers among CF patients than controls (47% versus 11%), but most strains carried by CF patients were non-toxigenic (77% versus 17%). “

Animal models of human microbiome and disease

Obese-type Gut Microbiota Induce Neurobehavioral Changes in the Absence of Obesity
Annadora J. Bruce-Keller – Biological Phychiatry

“Sequencing-based phylogenetic analysis confirmed the presence of distinct core microbiota between groups, with alterations in α- and β-diversity, modulation in taxonomic distribution, and statistically significant alterations to metabolically active taxa. “

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Microbiome Digest, July 25

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A year worth of oral/stool samples shows relative stability, antibiotics and preterm infants, reagent contamination, and 42. Have a great weekend!

 

Oral and gut microbiome

Screen Shot 2014-07-25 at 9.45.01 PMHost lifestyle affects human microbiota on daily timescales – Lawrence A David – Genome Biology

“Here, we link over 10,000 longitudinal measurements of human wellness and action to the daily gut and salivary microbiota dynamics of two individuals over the course of one year. These time series show overall microbial communities to be stable for months. However, rare events in each subjects’ life rapidly and broadly impacted microbiota dynamics. “

Pregnancy and Birth

Screen Shot 2014-07-25 at 9.44.20 PMThe impact of postnatal antibiotics on the preterm intestinal microbiome – Majd Dardas – Pediatric Research

“Rectal (fecal) swabs were collected at 10 and 30 d and analyzed by 16S rRNA pyrosequencing. At both time points, we examined the rectal microbiome from infants who received only 2 d of antibiotics and those who received at least 7 d of antibiotics.”

Techniques

Screen Shot 2014-07-25 at 9.45.50 PMReagent contamination can critically impact sequence-based microbiome analyses – Susannah Salter – BioRxiv (preprint)

“In this study we demonstrate that contaminating DNA is ubiquitous in commonly used DNA extraction kits, varies greatly in composition between different kits and kit batches, and that this contamination critically impacts results obtained from samples containing a low microbial biomass. “

Dengue

Speaking about “matter of timing”, seems like this paper came out a bit too late.
Screen Shot 2014-07-25 at 9.46.14 PMDengue and the World Football Cup: A Matter of Timing – Christovam Barcellos, Rachel Lowe – PLOS Neglected Tropical Diseases

“We provide a nationwide risk map, averaging June dengue incidence rates for 2001–2012. The areas along the Amazonian rivers and in the inner portions of southernmost states are actually low-risk areas, while elevated dengue risk is found in the central Brazilian plateau.”

Infection and host response

Don’t forget your towel! Even the issue number, 1004201, contains the “The Answer to the Ultimate Question of Life, the Universe, and Everything”. Perfection.
Screen Shot 2014-07-25 at 9.46.22 PMMicrobial Egress: A Hitchhiker’s Guide to Freedom – Ana Traven, Thomas Naderer – PLOS Pathogens

“The Restaurant at the End of the Infection — Macrophages as Host Cells”
“So Long and Thanks for All the Inflammatory Cell Death”

Dr. Bik’s Picks

crowSmarter than a first-grader? Crows can perform as well as 7- to 10-year-olds on cause-and-effect water displacement tasks

“New research conducted by UC Santa Barbara’s Corina Logan, with her collaborators at the University of Auckland in New Zealand, demonstrates the birds’ intellectual prowess may be more fact than fiction.”

JBC Journal of Biological ChemistryFour billion-year-old chemistry in cells today – Phys.org

“Parts of the primordial soup in which life arose have been maintained in our cells today according to scientists at the University of East Anglia.”

Screen Shot 2014-07-25 at 9.47.50 PMDustup Over Lionfish Science Fair Project – Bob Grant – The Scientist

A former graduate student says he feels slighted by a failure to attribute his contributions to a line of research regarding the salinity tolerances of an invasive species. “I’m not sure what happened, but my main issue is that the national media has presented a story that is sensationalized, and has left me out of the picture.”

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Microbiome digest, July 24

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Introducing the crAssphage, an 84 bp BLAST from the past, archaea in the Savannah, metabolomics of racehorse microbiome, and X-raying headphones.

Human oral microbiome

Proceedings RoyalMolecular analysis of ancient caries – Marc Simón – Proceedings of the Royal Society, Biological Sciences

“An 84 base pair sequence of the Streptococcus mutans virulence factor, known as dextranase, has been obtained from 10 individuals from the Bronze Age to the Modern Era in Europe and from before and after the colonization in America. “

Human gut microbiome

Nature CommunicationsA highly abundant bacteriophage discovered in the unknown sequences of human faecal metagenomes – Bas E. Dutilh – Nature Communications

“Here we describe the discovery of a previously unidentified bacteriophage present in the majority of published human faecal metagenomes, which we refer to as crAssphage.”

Gut family SchlossThe dynamics of a family’s gut microbiota reveal variations on a theme – Patrick D Schloss – Microbiome

“Using 16S rRNA gene and metagenomic shotgun sequence data, it was possible to distinguish the family from a cohort of normal individuals living in the same geographic region and to differentiate each family member”

Pregnancy and Birth

Screen Shot 2014-07-24 at 05.53PM, Jul 24An unnecessary cut? – Sky Dylan-Robbins – The New Yorker

“The most common operating-room procedure in the United States is the Cesarean section. “

Animal microbiome

Equine Vet JournalCharacterisation of the faecal metabolome and microbiome of Thoroughbred racehorses – C. J. Proudman – Equine Veterinary Journal

“Faecal metabolome was characterised using thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS), with spectral analysis performed using AMDIS and compared against the NIST database. Taxonomic description of the faecal microbiota was achieved using error-corrected 454 pyrosequencing data from 16S rRNA gene amplicons”

Journal of MicrobiologyPyrosequencing-based analysis of fecal microbial communities in three purebred pig lines – Edward Alain B. Pajarillo – Journal of Microbiology

“Taxon-dependent and -independent analyses were performed to evaluate differences in the fecal bacterial communities and to identify bacterial genera that can be used to discriminate breeds, following high-throughput pyrosequencing of 16S rRNA genes. “

Environmental microbiome

Screen Shot 2014-07-24 at 05.55PM, Jul 24Seasonal Effects in a Lake Sediment Archaeal Community of the Brazilian Savanna – Thiago Rodrigues – Archaea

“Here we describe for the first time the diversity of archaeal communities from freshwater lake sediments of the Cerrado in the dry season and in the transition period between the dry and rainy seasons, when the first rains occur. Gene libraries were constructed, using Archaea-specific primers for the 16S rRNA and amoA genes.”

Screen Shot 2014-07-24 at 05.56PM, Jul 24Spatial patterns and links between microbial community composition and function in cyanobacterial mats – Mohammad A. Al-Najjar – Frontiers in Microbiology

“Similar clustering was found when the community composition of the mats’ cyanobacterial layers were compared by automated ribosomal intergenic spacer analysis, indicating a significant link between the microbial community composition and function. “

MicrobeNetNew Joint Initiative from the Knight and Sogin Labs as a Follow-up to the MoBEDAC Initiative – Embriette Hyde

“By the end of the funded period, standard 16S rRNA and ITS (fungal) analysis pipelines will be developed and made available to the MoBe community, 16S rRNA and ITS databases will be markedly improved, QIIME and VAMPS will be tightly integrated into a new database engine called QiiTA to facilitate analysis by all MoBe researchers, and two major training workshops will be offered. “

Dr. Bik’s PicksDNA

DNA mostly ‘junk?’ Only 8.2 percent of human DNA is ‘functional’, study finds – Science Daily

“This figure is very different from one given in 2012, when some scientists involved in the ENCODE (Encyclopedia of DNA Elements) project stated that 80% of our genome has some biochemical function.”

Screen Shot 2014-07-24 at 05.58PM, Jul 24Sex differences in medicine – BeWell – Stanford University

“A man can be diagnosed with the same disease as a woman, and yet the course the disease takes in each could prove very different. And a treatment which works for one gender may prove ineffective for the other. “

corksIs Climate Change Ruining Wine Corks? – Kelly Dickerson – LiveScience

“Many people may only worry about corks when it’s time to pop the Champagne, but some experts are worried about wine cork quality, which has been mysteriously in decline for almost 20 years.“

Headphone x rayDoc X-Rays His Broken Headphones to Fix Them – Bahar Gholipour – LiveScience

“”Closed fracture of a speaker wire within its rubber/plastic sleeve is a rare headphone injury, usually due to a traction trauma,” Skalski wrote in his report of the case.”

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Microbiome digest, July 23

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Just one post today. Invading oral bacteria found in liver cirrhosis patients guts, obesity, biofilms and dispersal, motile and electric bacteria, dengue, and Weird Al Yankovic.

General microbiome

Screen Shot 2014-07-23 at 7.12.37 PMRadio show: City Visions: Exploring the Human Microbiome

“City Visions host David Onek explores these questions and more with Bay Area leading researchers Katie Pollard of the Gladstone Institutes, Susan Lynch of UCSF, and Peter diLaura of Second Genome.”

Human gut microbiome

Nan Qin Nature GutAlterations 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… Most (54%) of the patient-enriched, taxonomically assigned species are of buccal origin, suggesting an invasion of the gut from the mouth in liver cirrhosis. “

Lancet DiabetesObesity, inflammation, and the gut microbiota – Amanda J Cox – The Lancet Diabetes & Endocrinology

“In this Review, we provide evidence supporting perturbation of the intestinal microbiota and changes in intestinal permeability as potential triggers of inflammation in obesity.”

ParasitesOpinion: (Self-) infections with parasites: re-interpretations for the present
Julius Lukeš – Trends in Parasitology

“Here, we critically review cases in which humans were deliberately infected with parasites. Moreover, we summarize the contribution of (self-) infections and propose protist and helminth candidates, chosen on the basis of several criteria, to test as possible therapy for selected human diseases.”

General Microbiology

Screen Shot 2014-07-23 at 7.14.29 PMDispersed cells represent a distinct stage in the transition from bacterial biofilm to planktonic lifestyles – Song Lin Chua – Nature Communications

“Here we use single-nucleotide resolution transcriptomic analysis to show that the physiology of dispersed cells from Pseudomonas aeruginosa biofilms is highly different from those of planktonic and biofilm cells. “

Screen Shot 2014-07-23 at 7.15.00 PMBrownian motion? – Bacteria swim with bodies and flagella – Kevin Stacey – Brown University

“Using a new technique to track the swimming motion of a single bacterium, researchers have discovered that the movement of the bacterium’s body — not just thrust from the flagellum — allow movement through fluids.”

NewScientistBacteria that don’t need to eat: Meet the electric life forms that live on pure energy – Catherine Brahic – New Scientist

“Unlike any other living thing on Earth, electric bacteria use energy in its purest form – naked electricity in the shape of electrons harvested from rocks and metals. “

NatureCell communication: Stop the microbial chatter – Vivien Marx – Nature

“Bacteria can coat everything from thermal springs to teeth. Researchers are looking for antibiotics that can subvert the signalling that the microbes use to carve their niche.”

Dengue

Screen Shot 2014-07-23 at 7.19.32 PMSafety, immunogenicity and efficacy of a recombinant tetravalent dengue vaccine: A meta-analysis of randomized trials – Vivaldo G. da Costa – Vaccine

“..we conducted a meta-analysis to determine a more precise estimate of the overall parameters of safety, immunogenicity and efficacy of CYD-TDV. A data search was conducted in the PubMed, Medline, Cochrane Central Register of Controlled Trials and SciELO databases with defined selection criteria.”

Screen Shot 2014-07-23 at 7.19.57 PMKinome siRNA screen identifies novel cell-type specific dengue host target genes – Yong-Jun Kwon – Antiviral Research

“To identify novel human host cell targets important for dengue virus infection and replication, an image-based high-throughput siRNA assay screening of a human kinome siRNA library was conducted using human hepatocyte cell line Huh7 infected with a recent dengue serotype 2 virus isolate BR DEN2 01-01.”

Dr. Bik’s Picks

Bat polarizationA functional role of the sky’s polarization pattern for orientation in the greater mouse-eared bat – Stefan Greif – Nature Communications

“Here we demonstrate that the female greater mouse-eared bat (Myotis myotis) uses polarization cues at sunset to calibrate a magnetic compass, which is subsequently used for orientation during a homing experiment. “

Screen Shot 2014-07-23 at 7.20.54 PMScience and politics: Hello, Governor – Virginia Gewin – Nature

“When California’s governor enlisted the aid of two palaeoecologists, their careers took an unusual turn.”

Screen Shot 2014-07-23 at 7.21.49 PMYouTube distraction: Foil – Weird Al Yankovic music video

“fungal rot, bacterial formation, microbes, enzymes, mould and oxidation”

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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 digest, July 21

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Today we have articles on two microbiome pioneers: Rob Knight and Jeffrey Gordon, as well as papers on periodontitis, eczema, Crohn’s disease, and Helicobacter.

General microbiome

The effects of the microbiota on the host immune system – Jacek Karczewski – Autoimmunity

“This review is focused on host–microbiota interactions, specifically on influence of bacterial-derived signals on immune cell function and the mechanisms by which these signals modulate the development and progression of inflammatory and autoimmune diseases.”

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

“We envision that the lack of survivability of some of the probiotic candidates within such hostile milieu of GIT may negatively affect the coevolving process of bacteria in human host and hence impact the endpoint health promotion goals.”

40 under 40: Rob Knight – Cell

“Some dead scientists who I would have loved to have had the opportunity to work with include Carl Woese, Richard Feynman, Francis Crick, Erwin Chargaff, Sewall Wright, Benjamin Franklin, Antonie van Leeuwenhoek, Robert Boyle, Eratosthenes, and Lucretius. These lists are intended to be illustrative rather than exhaustive; according to my NSF Conflict of Interest form I have written grants or papers with about 750 people, all of whom I admire.”

Jeffrey I. Gordon, M.D., Will Receive Pitt’s Dickson Prize at Science 2014—Sustain It! – University of Pittsburgh

“A scientist who has explored how the tens of trillions of microbes that live in the gastrointestinal tract and their genes influence human physiology, metabolism and nutritional status will receive the University of Pittsburgh’s 2014 Dickson Prize in Medicine.”

Oral microbiome

Quantitative analysis of classical and new putative periodontal pathogens in subgingival biofilm: a case–control study – N. N. Al-hebshi – Journal of Periodontal Research

“Pooled subgingival biofilm samples were obtained from 40 patients with chronic periodontitis and 40 healthy controls. Taqman q-PCR assays were used to determine the absolute and relative counts of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Parvimonas micra, Filifactor alocis, oral Synergistetes and oral TM7s. “

Skin microbiome

Review: Microbiota in Healthy Skin and in Atopic Eczema – Giuseppe Baviera – BioMed Research International

“This review also highlights recent observations on the importance of innate immune systems and the relationship with normal skin microflora for the maintenance of healthy skin.”

Gastric microbiome

Microbial Profile of the Stomach: Comparison between Normal Mucosa and Cancer Tissue in the Same Patient – Incheol Seo – Journal of Bacteriology and Virology

“In this study, we identified differences in the microbial communities between gastric cancer and normal gastric mucosa by comparing the microbiomes of tissues from the same patients. The clustering analysis results showed different bacterial communities between normal gastric mucosa and gastric cancer.”

Motility and Chemotaxis Mediate the Preferential Colonization of Gastric Injury Sites by Helicobacter pylori – Eitaro Aihara – PLOS Pathogens

“Using anesthetized mice in which we have induced microscopic damage to the stomach surface, we find that H. pylori is able to rapidly detect and navigate towards this damage site. Within minutes, bacterial accumulation slows repair of the damage.”

Gut microbiome

Metabolic Modeling of Common Escherichia coli Strains in Human Gut Microbiome
Yue-Dong Gao – BioMed Research International

“we investigated the E. coli strains in human gut microbiome using deep sequencing data and reconstructed genome-wide metabolic networks for the three most common E. coli strains, including E. coli HS, UTI89, and CFT073. “

Analysis of Gut Microbiome and Diet Modification in Patients with Crohn’s Disease [PDF] – Sumathi Sankaran Walters – Symbiosis

“Fecal samples were obtained from patients with Crohn’s disease in a pilot diet crossover trial comparing the effects of a specific carbohydrate diet (SCD) versus a low residue diet (LRD) on the composition and complexity of the gut microbiota and resolution of IBD symptoms. The gut microbiota composition was assessed using a high-density DNA microarray PhyloChip “

Review: Managing the manager: Gut microbes, stem cells and metabolism –
M. Serino – Diabetes & Metabolism

“The LPS-sensitive cell types can be seen within bone marrow-derived cells (BMC), which are involved in the development of inflammation in the adipose tissue of obese and type 2 diabetic mice. “

 

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Human microbiome, July 17

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

Oral microbiome

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

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

Respiratory microbiome

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

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

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

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

Gut microbiome

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

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

Pregnancy and birth

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

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

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

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

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

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

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Human (and fish) microbiome, July 16

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

Human oral microbiome

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

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

Human gut microbiome

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

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

Pregnancy and birth

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

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

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

Fish microbiome

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

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

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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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