Category Archives: Human oral

Human microbiome, August 14, 2014

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Culturing TM7, antibiotics early in life and obesity, preterm labor, breast milk, two articles by Carl Zimmer and one by Jop de Vrieze.

Pregnancy and Birth

Science has a special this week on Parenting, with a couple of relevant papers:

Preterm labor: One syndrome, many causes – Roberto Romero, Sudhansu K. Dey, Susan J. Fisher – Science

“We summarize the current understanding of the mechanisms of disease implicated in this condition and review advances relevant to intra-amniotic infection, decidual senescence, and breakdown of maternal-fetal tolerance.”

Nature’s first functional food – Trisha Gura – Science

“Building upon a century-old study that first indicated that milk nourished certain bacteria in infants, the new work has characterized the complexity of breast milk carbohydrates called oligosaccharides, or HMOs, that particularly nourish one species of beneficial bacteria.”

The taste of things to come – Emily Underwood – Science

“Indeed, studies in human infants and animals suggest that we may start to learn and love different flavors as early as in the womb.”

Human oral microbiome

Axenic Culture of a Candidate Division TM7 Bacterium from the Human Oral Cavity and Biofilm Interactions with Other Oral Bacteria – Valeria Soro – Applied and Environmental Microbiology

“Successive rounds of enrichment in laboratory media led to the isolation of a pure culture of one of these candidate division TM7 phylotypes.”

Human gut microbiome

Review: Host-microbial interactions in the metabolism of therapeutic and diet-derived xenobiotics – Rachel N. Carmody and Peter J. Turnbaugh – Journal of Clinical Investigation

“Here, we integrate results from classic and current studies of the direct and indirect impacts of the gut microbiome on the metabolism of therapeutic drugs and diet-derived bioactive compounds. “

Taking the Yuck Out of Microbiome Medicine – Carl Zimmer – National Geographic

“I can still remember the shock I felt when I heard about fecal microbiota transplants for the first time. It is not the sort of thing you forget.”

Our Microbiome May Be Looking Out for Itself – Carl Zimmer – New York Times

“But in the journal Bioessays, a team of scientists has raised a creepier possibility. Perhaps our menagerie of germs is also influencing our behavior in order to advance its own evolutionary success — giving us cravings for certain foods, for example.”

Animal models of microbiome research

Altering the Intestinal Microbiota during a Critical Developmental Window Has Lasting Metabolic Consequences – Laura M. Cox – Cell

Press coverage: Taking antibiotics early in life leaves mice prone to obesity – Jop de Vrieze

“A new study of mice shows that interrupting the development of gut microbial populations with low doses of antibiotics early in life disturbs their metabolism and boosts the risk of obesity later on.”

The Gut Microbiota and Developmental Programming of the Testis in Mice – Maha Al-Asmakh – PLOS ONE

“Interestingly, exposure of GF mice to Clostridium Tyrobutyricum (CBUT), which secrete high levels of butyrate, restored the integrity of the BTB and normalized the levels of cell adhesion proteins. “

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Human microbiome, August 12, 2014

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Oral microbiome in Aboriginals, gut microbiome and probiotics.

Human oral microbiome

Age-dependent changes in Porphyromonas gingivalis and Prevotella species/phylotypes in healthy gingiva and inflamed/diseased sub-gingival sites – Mangala A. Nadkarni – Clinical Oral Investigations

“The aims of the present study were to establish the age-dependent relationship between sub-gingival profiles of 22 Prevotella species/phylotypes in children, adolescents and adults from an isolated Aboriginal community and, further, to use this information to identify Prevotella species that could serve as microbial risk indicators.”

The effect of propidium monoazide treatment on the measured bacterial composition of clinical samples after the use of a mouthwash – R. A. M. Exterkate – Clinical Oral Investigations

“Propidium monoazide (PMA) has been used to overcome this problem, by preventing the amplification of DNA from membrane-damaged cells. The aim of this study was to evaluate the use of PMA when measuring compositional shifts in clinical samples after mouthwash use.”

Human gut microbiome

Is eating behavior manipulated by the gastrointestinal microbiota? Evolutionary pressures and potential mechanisms – Joe Alcock – BioEssays

“We review several potential mechanisms for microbial control over eating behavior including microbial influence on reward and satiety pathways, production of toxins that alter mood, changes to receptors including taste receptors, and hijacking of the vagus nerve, the neural axis between the gut and the brain”

Influence of the microbiota on vaccine effectiveness – Yanet Valdez – Trends in Immunology

“Recent findings suggest novel complex mechanisms by which the microbiome impacts immune cell development and differentiation.”

Current Status and Prospects of Intestinal Microbiome Studies – Dong Soo Han – Intest Res

“Evidences have implicated gut microbes in the development of IBD, but no causative microorganisms have been identified.”

Synbiotic Lactobacillus acidophilus NCFM and cellobiose does not affect human gut bacterial diversity but increases abundance of lactobacilli, bifidobacteria and branched-chain fatty acids: a randomized, double-blinded cross-over trial – Gabriella C. van Zanten – FEMS Microbiology Ecology

“Furthermore, 454 tag encoded amplicon pyrosequencing was used to monitor the effect of synbiotic on the composition of the microbiota. “

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Microbiome digest, August 7, 2014

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Microbiome and caries, colorectal cancer, and inflammatory bowel diseases. Microbiomes of fish, dogs, and mosses, microscopic life in an asphalt lake, and the Picks.

Human mouth microbiome

Identification of the Microbiota in Carious Dentin Lesions Using 16S rRNA Gene Sequencing – Junko Obata – PLOS ONE

“In the present study, the bacterial communities in the carious dentin of Japanese subjects were analyzed comprehensively with molecular approaches using the 16S rRNA gene.”

Human gut microbiome

The Human Gut Microbiome as a Screening Tool for Colorectal Cancer – Joseph P. Zackular, Mary A.M. Rogers, Mack T. Ruffin IV, and Patrick D. Schloss – Cancer Prevention Research

“Analysis of the gut microbiome from stool samples revealed both an enrichment and depletion of several bacterial populations associated with adenomas and carcinomas.”

Manipulation of Microbiome, a Promising Therapy for Inflammatory Bowel Diseases – Dapeng Jin, Hongyu Zhang, and Jun Sun – Clinical & Cellular Immunology

“In this review, we summarize the current knowledge of how changes in microbiota may affect the pathogenesis of IBD. “

A perspective on the complexity of dietary fiber structures and their potential effect on the gut microbiota – Bruce R. Hamaker, Yunus E. Tuncil – Journal of Molecular Biology

“the article encourages the building of a framework of information to manipulate the colon microbiota in a predicted way for improved health”

 

Human microbiome after death

Distinctive thanatomicrobiome signatures found in the blood and internal organs of humans – Ismail Can – Journal of Microbiological Methods

“We compared the effectiveness of two methods by amplifying the 16S rRNA genes and sequencing the amplicons from four cadavers”

Animal models of human microbiome

Disturbance of the gut microbiota in early-life selectively affects visceral pain in adulthood without impacting cognitive or anxiety-related behaviors in male rats
S.M. O’Mahony – Neuroscience

“Neonatal antibiotic treatment leads to an increase in visceral sensitivity in adulthood in rats.”

Dog microbiome

The Unculturables: targeted isolation of bacterial species associated with canine periodontal health or disease from dental plaque – Ian J Davis, Christopher Bull, Alexander Horsfall, Ian Morley and Stephen Harris – BMC Microbiology

“Using a quantitative polymerase chain reaction (qPCR) directed approach a range of microbiological media were screened and optimized to enrich for previously uncultivated target species. A systematic screening methodology was then employed to isolate the species of interest. ‘

Fish microbiome

Characterization of Microbiota Composition and Presence of Selected Antibiotic Resistance Genes in Carriage Water of Ornamental Fish – Lenka Gerzova – PLOS ONE

“In this study we therefore characterized the prevalence of selected antibiotic resistance genes in the microbiota found in the carriage water of ornamental fish originating from 3 different continents.”

Insect microbiome

The mosquito microbiota influences vector competence for human pathogens – Nathan J Dennison, Natapong Jupatanakul, George Dimopoulos – Current Opinion in Insect Science

“Understanding the interaction between the vector, its microbiota and transmitted pathogens will provide novel opportunities to limit disease transmission.”

Plant microbiome

Bacterial-biota dynamics of eight bryophyte species from different ecosystems
Faisal Hammad Mekky Koua – Saudi Journal of Biological Sciences

“..we utilized the 16S rRNA gene PCR-DGGE and subsequent phylogenetic analyses to investigate the bacterial community of eight bryophyte species collected from three distinct ecosystems from western Japan.”

Soil and water microbiome

Two Neumann U students discover new types of viruses – CatholicPhilly.com

“They collected arthrobacter (a bacteria present in soil) from under trees and near lakes, found and filtered out the phages that were present, and then studied phage anatomy and life cycles.”

Water droplets in oil are microhabitats for microbial life – Rainer U. Meckenstock – Science

“In Pitch Lake, Trinidad and Tobago—the world’s largest asphalt lake—we found that microorganisms are metabolically active in minuscule water droplets (1 to 3 microliters) entrapped in oil. “

Microbiome of the built environment

Halophilic Microorganisms Are Responsible for the Rosy Discolouration of Saline Environments in Three Historical Buildings with Mural Paintings – Jörg D. Ettenauer – PLOS ONE

“In order to get a complete overview of this biodeterioration process, we investigated the microbial communities in saline environments causing the rosy discolouration of mural paintings in three Austrian historical buildings using a combination of culture-dependent and -independent techniques as well as microscopic techniques.”

Metagenomics

High-resolution metagenomics – Eran Mick & Rotem Sorek – Nature Biotechnology

In this issue, Nielsen et al. present a powerful method for interpreting metagenomic data at the level of individual genomes without relying on reference sequences of cultured isolates, which can be generated for only a small fraction of microbial life.

Microbes in the News

The Quantified Microbiome Self – Carl Zimmer – National Geographic

“But as I read the journal Genome Biology today, I decided that someday I might surrender to the Quantified Self movement. I’ll just have to wait till I can track my trillions of microbes from one day to the next.”

Science and Career

Ph.D.’s, come out of the closet! – Lina Nilsson – Science

“If you promise not to tell Fisher’s Ph.D. adviser (or mine), I’ll let you in on this well-hidden truth: Fisher isn’t planning to pursue an academic career.”

Bik’s Picks

Stress during pregnancy can be passed down through generations, rat study shows – Science Daily

“Scientists investigating pregnancies in four generations of rats show that inherited epigenetic effects of stress could affect pregnancies for generations.”

This Is Your Brain on Fish – James Hamblin – The Atlantic

“Thicker, stronger, and more resilient. Once a week is all it takes, new research says.”

10 Great Novels That Will Make You More Passionate About Science – Charlie Jane Anders – io9

“A lot of the best science fiction features scientists who solve problems and make breakthroughs.”

Scientist looking forward to weekend of binge-experimenting – The Allium

“Imperial college Scientist Dr. Lou Pole announced earlier today that he was going to spend the entirety of this weekend binge-experimenting.”

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Human microbiome digest, August 5, 2014

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

Pregnancy and Birth

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

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

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

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

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

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

Human mouth microbiome

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

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

 Respiratory microbiome

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

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

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

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

Vaginal microbiome

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

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

Human gut microbiome

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

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

Animal models of human microbiome

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

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

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

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

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

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

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Human microbiome, July 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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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 and bioreactor microbiome, July 18

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An upcoming radio show on the human microbiome that looks interesting, dental calculus from prehistoric skeletons (without bacterial analysis unfortunately), and animals models of microbiome research.

General microbiome

City Visions: Exploring the Human Microbiome – KALW public radio – Monday July 21 at 7 pm at 91.7 FM in San Francisco

“Join host David Onek as we explore these questions and more with Bay Area researchers who are leading the new field of microbiome exploration and discovery.”

Oral microbiome

Dental Calculus Reveals Unique Insights into Food Items, Cooking and Plant Processing in Prehistoric Central Sudan – Stephen Buckley – PLOS ONE

“Here we present a suite of results from the multi-period Central Sudanese site of Al Khiday. We demonstrate the ingestion in both pre-agricultural and agricultural periods of Cyperus rotundus tubers. “

Animal models of gut microbiota and disease

Gut Microbial Metabolism Drives Transformation of Msh2-Deficient Colon Epithelial Cells – Antoaneta Belcheva – Cell

“We report that altering the microbiota composition reduces CRC in APCMin/+MSH2−/− mice, and that a diet reduced in carbohydrates phenocopies this effect. “

Exposure to a social stressor disrupts the community structure of the colonic mucosa-associated microbiota – Jeffrey D Galley – BMC Microbiology

“..we used high throughput pyrosequencing to assess the effects of a single 2-hour exposure to a social stressor, called social disruption (SDR), on colonic mucosa-associated microbial profiles of C57BL/6 mice.”

Bioreactor microbiome

Ethyl tert-Butyl Ether (ETBE)-degrading microbial communities in enrichments from polluted environments – Yoann Le Digabel – Journal of Hazardous Materials

“Clone libraries of the 16S rRNA gene were prepared from each enrichment. The analyses of the DNA sequences obtained showed different taxonomic compositions with a majority of Proteobacteria in three cases.”

Microbial community structure of wastewater treatment subjected to high mortality rate due to ozonation of return activated sludge – S. Isazadeh – Journal of Applied Microbiology

“The bacterial community structures were investigated by 16S rRNA gene amplicon high-throughput pyrosequencing and fluorescence in situ hybridization (FISH). The structures remained highly similar throughout the experiment despite the ozone treatment.”

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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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