Category Archives: Human gut

Human microbiome digest, August 19, 2014

Posted on by

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]

Microbiome digest, August 17, 2014

Posted on by

Childhood undernutrition and the gut microbiome, hibernating ground squirrels, Sphagnum, nematodes, and forensic discrimination of soils.

Human gut microbiome

An evolving perspective about the origins of childhood undernutrition and nutritional interventions that includes the gut microbiome – Tahmeed Ahmed – Annals of the New York Academy of Sciences

“This paper summarizes work on mechanisms underlying the varied manifestations of childhood undernutrition and discusses current gaps in knowledge and challenges to our understanding of undernutrition and infection/immunity throughout the human life cycle, focusing on early childhood growth. ”

Animal microbiome

Hibernation alters the diversity and composition of mucosa-associated bacteria while enhancing antimicrobial defense in the gut of 13-lined ground squirrels – Kimberly A. Dill-McFarland – Molecular Ecology

“We used 16S rRNA pyrosequencing and cecal tissue protein analysis to investigate the effects of hibernation on the mucosa-associated bacterial microbiota and host responses in 13-lined ground squirrels.”

Diversity of Bacteria Carried by Pinewood Nematode in USA and Phylogenetic Comparison with Isolates from Other Countries – Diogo Neves Proença – PLOS ONE

“The objective of this study was to evaluate the diversity of the bacterial community carried by B. xylophilus, isolated from different Pinus spp. with PWD in Nebraska, United States. “

Plant microbiome

The Sphagnum microbiome supports bog ecosystem functioning under extreme conditions – Anastasia Bragina – Molecular Ecology

“We identified a high functional diversity within the Sphagnum microbiome applying an Illumina-based metagenomic approach followed by de novo assembly and MG-RAST annotation.”

Soil microbiome

Random Whole Metagenomic Sequencing for Forensic Discrimination of Soils – Anastasia S. Khodakova – PLOS ONE

“Shotgun, whole genome amplification (WGA) and single arbitrarily primed DNA amplification (AP-PCR) based sequencing techniques were then used to generate soil metagenomic profiles”

Microbial Community Structure of Relict Niter-Beds Previously Used for Saltpeter Production – Takashi Narihiro – PLOS ONE

“In this study, the microbial community structures within nine relict niter-bed soils were investigated using 454 pyrotag analysis targeting the 16S rRNA gene and the bacterial and archaeal ammonia monooxygenase gene (amoA). “

How Does Conversion of Natural Tropical Rainforest Ecosystems Affect Soil Bacterial and Fungal Communities in the Nile River Watershed of Uganda? – Peter O Alele – PLOS ONE

“Overall, our results suggest that soil microbial communities are relatively resilient to forest conversion and despite a substantial and consistent change in the soil environment, the effects of conversion differed widely among sites. “

Soil-Borne Microbial Functional Structure across Different Land Uses – Eiko E. Kuramae – The Scientific World Journal

“In a multivariate regression tree analysis of soil physicochemical properties and genes detected by functional microarrays, the main factor that explained the different microbial community functional structures was C : N ratio.”

Water microbiome

Temperature response of denitrification and anammox rates and microbial community structure in Arctic fjord sediments – Andy Canion – Environmental Microbiology

“Community structure in intact sediments and slurry incubations was determined using Illumina MiSeq SSU rRNA gene sequencing.”

Complex communities of small protists and unexpected occurrence of typical marine lineages in shallow freshwater systems – Marianne Simon – Environmental Microbiology

“We carried out a comparative study based on massive pyrosequencing of amplified 18S rRNA gene fragments of protists in the 0.2-5 μm-size range in one brook and four shallow ponds located in the Natural Regional Park of the Chevreuse Valley, France.”

Metagenomics

Impact of single-cell genomics and metagenomics on the emerging view of extremophile “microbial dark matter” – Brian P. Hedlund- Extremophiles

“Unraveling the mysteries of these candidate phyla is a grand challenge in microbiology and is especially important in habitats where they are abundant, including some extreme environments and low-energy ecosystems.”

Metabolomics

Metabolic Modelling of Spatial Heterogeneity of Biofilms in Microbial Fuel Cells Reveals Substrate Limitations in Electrical Current Generation – Nadeera Jayasinghe – Biotechnology Journal

“The goal of this work is to develop a model that integrates genome-scale metabolic models with the model of biofilm environment. “

Bioinformatics

Rarefaction and extrapolation of phylogenetic diversity – Anne Chao – Methods in Ecology and Evolution

“We develop in this paper the “PD accumulation curve” (an extension of the species accumulation curve) to depict how PD increases with sampling size and sample completeness.”

Microbes in the news

Can’t Stick to That Diet? Blame Your Gut Bacteria – Nolan Feeney – Time

“The gut microbiome, the collection of all the microbes in our digestive tracts, may influence our food choices and behavior, suggests a new study that recently appeared in the journal BioEssays.”

How Clean Is Your Produce? Testing Fruit For Bacteria – WFMyNews2.com

“Ellis took samples of the fruits one by one and placed the samples on a petri dish. She then washed some of the lettuce and repeated the testing procedure on both the head of lettuce and the pre-washed bag of lettuce, in 72-hours the results were in.”

Bik’s Picks

9/11 dust cloud may have caused widespread pregnancy issues – ScienceDaily

“Pregnant women living near the World Trade Center during the 9/11 attacks experienced negative birth outcomes, according to a new paper.”

Volunteers on the scent of science with whale carcass – Peter Fimrite – SF Gate

“If there’s anything as enjoyable to Dan Sudran as sawing through the stinking blubber of a whale carcass and extracting bones from the gooey tissues, it would be showing the results to children.”

Alaska’s Shrinking Glaciers Seen from Space – Kelly Dickerson – LiveScience

“Compared with a vintage satellite photo of the region, an image taken from space last year reveals just how much the glaciers have shrunk over the past 26 years.”

[hr]

Microbiome digest, August 15, 2014

Posted on by

Today we got donkey, goat, and camel milk, deodorants, kitten microbiomes, and coffee as a new mouth rinse.

Pregnancy and birth

Gut microbiota in preterm infants with gross blood in stools: A prospective, controlled study – Mohamed Ben Said – Early Human Development

“Each case was paired with two controls who were hospitalized in the same unit and were matched for gestational age and birth weight. The diversity of the gut microbiota was analyzed using 16S rRNA gene PCR and temporal temperature gel electrophoresis. “

Human oral microbiome

Antibacterial effect of coffee: calcium concentration in a culture containing teeth/biofilm exposed to Coffea Canephora aqueous extract – N. Meckelburg – Letters in Applied Microbiology

“This study revealed an inhibitory action of Coffea canephora against dental biofilm. This coffee species caused bacterial lysis and consequent release of calcium into the medium.”

Human gut microbiome

Review: Exploring gut microbes in Human health and disease: pushing the envelope
Jun Sun, Eugene B. Chang – Genes & Diseases

“In this review and commentary, we highlight recent progress in our understanding of the intestinal microbiome in the context of health and diseases, focusing on mechanistic concepts that underlie the complex relationships between host and microbes.”

Review: Emergence of fecal microbiota transplantation as an approach to repair disrupted microbial gut ecology – Alexander Khoruts, Alexa R. Weingarden – Immunology Letters

“Mechanistic understanding will be required in development of next generation microbiota therapeutics, which may include FMT or defined microbial consortia.”

Gut Bacteria May Play a Role in Autism – Melinda Wenner Moyer – Scientific American

“One open question is whether these microbial differences drive the development of the condition or are instead a consequence of it. “

Skin microbiome

Deodorants and antiperspirants affect the axillary bacterial community – Chris Callewaert — Archives of Dermatological Research

“The effect of deodorants and antiperspirants on the axillary bacterial community was examined on nine healthy subjects, who were restrained from using deodorant/antiperspirant for 1 month. Denaturing gradient gel electrophoresis was used to investigate the individual microbial dynamics.”

Goat and Ass Milk microbiome

Analysis of raw goat milk microbiota: Impact of stage of lactation and lysozyme on microbial diversity – Elizabeth A. McInnis – Food Microbiology

“Milk from transgenic goats containing lysozyme had a similar microbiota over time.”

Fasscinating stuff: Cleopatra took daily baths in assmilk to keep her skin wrinklefree. Maybe lactic acid bacteria were her secret?  Biotyping of cultivable lactic acid bacteria isolated from donkey milk – D. Carminati – Letters in Applied Microbiology

“The large amounts of antimicrobial components and defence factors present in donkey’s milk provide protection from microbial infections and distinguish donkey’s milk from the milks of other mammals”

The Kitten Microbiome Project

“Keeping track of the cutest, fluffiest microbiome project around”

Insect microbiome

Microbial impacts on insect evolutionary diversification: From patterns to mechanisms
Fabrice Vavre, Natacha Kremer – Current Opinion in Insect Science

“Symbiosis can favor rapid shifts in host phenotypic traits, particularly through the contribution of symbionts to the host’s physiology.”

How resident microbes modulate ecologically-important traits of insects
Kerry M. Oliver, Adam J. Martinez – Current Opinion in Insect Science

“In addition to their better-known roles in nutrient provisioning and degrading plant polymers, there is emerging evidence that microorganisms also aid herbivores in countering plant defenses. “

Metabolomics

Building blocks for automated elucidation of metabolites: natural product-likeness for candidate ranking – Kalai Vanii Jayaseelan and Christoph Steinbeck – BMC Bioinformatics

“In this study, we investigated whether additional existing knowledge, such as the fact that the unknown compound is a natural product, can be used to improve the ranking of the correct structure in the result list after the structure elucidation process.”

Phages and viruses

Bacteriophage as effective decolonising agent for elimination of MRSA from anterior nares of BALB/c mice – Sanjay Chhibber – BMC Microbiology

“Phage MR-10, given along with mupirocin showed an additive effect and the combination was able to effectively eradicate the colonising MRSA population from the nares of mice by day 5.”

Crystal structure of a CRISPR RNA-guided surveillance complex bound to a ssDNA target – Sabin Mulepati, Annie Héroux, Scott Bailey – Science

“The structure reveals that the CRISPR RNA and target strands do not form a double helix but instead adopt an underwound ribbon-like structure. “

Bik’s Picks – weekend edition

15 Real-Life Scientists Share Their Favorite Science Fiction Books, Movies – Jacqueline Howard – Huffington Post

“There’s a big difference between science and science fiction, but there’s abundant evidence to suggest that sci-fi books and movies can spark a lifelong interest in science.”

After donkey and goat milk, this one was only appropriate: A Nice Tall Glass of Camel’s Milk – Olga Khazan – The Atlantic

“An oasis in the dromedary-dairy desert?”

Male Mathematicians Agree That Fields Medal Gender Balance Is Now OK – The Allium

“Now that a woman has won the fields medal, there is true and genuine equality and there is no need to worry any more about it.”

[hr]

Human microbiome, August 14, 2014

Posted on by

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. “

[hr]

Microbiome digest, August 13, 2014

Posted on by

Nose, glycan, butyrate, microbes on plastics, seawater microbial mats, and plants with microbes.

Respiratory microbiome

The nasal cavity microbiota of healthy adults – Christine M Bassis, Alice L Tang, Vincent B Young and Melissa A Pynnonen – Microbiome

“In our initial analysis, we compared the bacterial communities of the nasal cavity and the oral cavity from ten of these subjects.”

Gut microbiome

Glycan Degradation (GlyDeR) Analysis Predicts Mammalian Gut Microbiota Abundance and Host Diet-Specific Adaptations – Omer Eilam – mBio

“Based on GlyDeR, we found a clear connection between microbial glycan degradation and human diet, and we suggest a method for the rational design of novel prebiotics.”

Microbial-Derived Butyrate: An Oncometabolite or Tumor-Suppressive Metabolite? -Scott J. Bultman, Christian Jobin – Cell Host & Microbe

“Dietary factors, microbial composition, and metabolism are intimately intertwined into a complex network whose activities influence important intestinal functions”

Review: Collateral Damage: Microbiota-Derived Metabolites and Immune Function in the Antibiotic Era – Christopher A. Lopez – Cell Host & Microbe

“A disruption of gut-associated microbial communities by antibiotic treatment can result in a depletion of microbiota-derived metabolites, thereby enhancing pathogen susceptibility, impairing immune homeostasis, and contributing to the rise of certain chronic inflammatory diseases”

Animal model of microbiome

Differential Modulation by Akkermansia muciniphila and Faecalibacterium prausnitzii of Host Peripheral Lipid Metabolism and Histone Acetylation in Mouse Gut Organoids
Sabina Lukovac – mBio

“The aim of this study was to characterize effects of the microbiota on host epithelium using a novel ex vivo model based on mouse ileal organoids.”

Plant microbiome

Phyllosphere Microbiota Composition and Microbial Community Transplantation on Lettuce Plants Grown Indoors – Thomas R. Williams, Maria L. Marco – mBio

“We found that Romaine lettuce grown in the laboratory contained 10- to 100-fold lower numbers of bacteria than age-matched, field-grown lettuce.”

Fundamental Plant Chemicals Rooted in Bacteria – Jenna Iacurci – Nature World News

“A fundamental chemical pathway that all plants use to create the essential amino acid phenylalanine has now been traced to two groups of ancient bacteria, a new study reports.”

Water microbiome

Spatial and seasonal variation in diversity and structure of microbial biofilms on marine plastics in Northern European waters – Sonja Oberbeckmann – FEMS Microbial Ecology

“Denaturing Gradient Gel Electrophoresis (DGGE) and sequencing analysis revealed that plastisphere microbial communities on PET fragments varied both with season and location, and comprised of bacteria belonging to Bacteroidetes, Proteobacteria, Cyanobacteria and members of the eukaryotes Bacillariophyceae and Phaeophyceae. “

Molecular Ecology of Microbial Mats – Henk Bolhuis – FEMS Microbial Ecology

“Here, we summarize some of the latest developments in metagenomic analysis of three representative phototrophic microbial mat types (coastal, hot spring and hypersaline).”

Microbes in the news

Wearable structure of bacteria references antique animal bone corsets

“in terms of the material, it is grown from acetobacter xylinum, a strain of bacteria that produces a microbial cellulose textile as it consumes glucose.”

Bik’s Picks

Google Maps Dives Underwater – Scientific American

“Google has taken its ‘street view’ maps to a whole new level—namely, the ocean’s depths. “

[hr]

Human microbiome, August 12, 2014

Posted on by

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. “

[hr]

 

Human microbiome, August 11, 2014

Posted on by

Microbiome of Hadza Hunter, the premature infant gut, neonatal sepsis, skin and respiratory microbiome.

Microbiome general

BacterioFiles 178 – Hadza Hunters Have Heterogeneous Helpers (14 min) – Jesse Noar – BacterioFiles

“This episode: Modern hunter-gatherers have very different gut microbes from people from agricultural societies! “

“What is the FDA Going to Think?” – Negotiating Values through Reflective and Strategic Category Work in Microbiome Science – Katherine W. Darling – Science, Technology & Human Values

“Here, we describe how values are conceptualized and negotiated within microbiome research.”

Pregnancy and Birth microbiome

Patterned progression of bacterial populations in the premature infant gut – Patricio S. La Rosa – PNAS USA

“We demonstrate via 16S rRNA gene pyrosequencing of 922 specimens from 58 subjects that the gut microbiota of premature infants residing in a tightly controlled microbial environment progresses through a choreographed succession of bacterial classes“

Development of a multiplex real-time PCR assay for the rapid diagnosis of neonatal late onset sepsis – Marre van den Brand – Journal of Microbiological Methods

“we developed a real-time multiplex PCR assay tailored to LOS diagnosis which is easy-to-use, is applicable on small blood volumes and provides species-specific results within 4 h.”

Respiratory microbiome

Uncovering the hidden villain within the human respiratory microbiome – Chun Kiat Lee, Stephen James Bent – Diagnosis

“The review herein presents the current status of human airway microbiome research and highlights potential gaps which can be translated into research possibilities for future work on respiratory tract infection diagnosis”

Skin microbiome

The skin microbiome: potential for novel diagnostic and therapeutic approaches to cutaneous disease – Elizabeth A. Grice – Skin and Allergy News

“It is increasingly apparent that this collective set of microorganisms and their genetic material, the “microbiome”, contributes genetic diversity, modulates disease, influences metabolic processes, and is essential for immunity.”

Animal models of human microbiome

Citrobacter rodentium: infection, inflammation and the microbiota – James W. Collins – Nature Reviews Microbiology

“In this Review, we discuss recent studies in which C. rodentium has been used to study mucosal immunology, including the deregulation of intestinal inflammatory responses during bacteria-induced colitis and the role of the intestinal microbiota in mediating resistance to colonization by enteric pathogens. “

[hr]

Microbiome digest, August 7, 2014

Posted on by

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.”

[hr]

 

Human microbiome digest, August 5, 2014

Posted on by

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.”

[hr]

Microbiome digest, August 4, 2014

Posted on by

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

Human gut microbiome

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

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

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

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

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

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

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

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

Skin and wounds microbiome

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

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

Human respiratory microbiome

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

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

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

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

Fish microbiome

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

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

Soil microbiome

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

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

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

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

Water microbiome

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

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

Microbial Ecology

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

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

Probiotics

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

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

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

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

Microbes in the News

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

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

Truth about your toothbrush – Anne Agbaje – Bussiness Day Online

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

Metabolomics

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

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

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

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

Techniques

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

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

 

Bik’s Picks

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

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

 

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

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

[hr]