American Gut | Microbiome Digest

Phages and CRISPRs in human mouth, new metagenomes from MetaHit, and vaginal microbiota.

General microbiome

Review: An Overview of the Microbiome and the Effects of Antibiotics – Hillary Taggart – The Journal for Nurse Practitioners

“This review provides a basic introduction of what the microbiome is and how it plays a role in obesity, gastrointestinal, immune, and mental health, including a brief mention of implications for the pediatric population.”

Oral microbiome

Characterization of bacteriophage communities and CRISPR profiles from dental plaque – Mayuri Naidu (with David Pride) – BMC Microbiology

“We sampled the saliva and dental plaque from 4 healthy human subjects to determine whether plaque was populated by viral communities, and whether there were differences in viral communities specific to subject or sample type.”

Gut microbiome

An integrated catalog of reference genes in the human gut microbiome – Junhua Li – Nature Biotechnology

“Here we combined 249 newly sequenced samples of the Metagenomics of the Human Intestinal Tract (MetaHit) project with 1,018 previously sequenced samples to create a cohort from three continents that is at least threefold larger than cohorts used for previous gene catalogs. “

Identification and assembly of genomes and genetic elements in complex metagenomic samples without using reference genomes – H Bjørn Nielsen (and 142 other authors) – Nature Biotechnology

“Here we present a method, based on binning co-abundant genes across a series of metagenomic samples, that enables comprehensive discovery of new microbial organisms, viruses and co-inherited genetic entities and aids assembly of microbial genomes without the need for reference sequences.”

Commensal microbial regulation of natural killer T cells at the frontiers of the mucosal immune system – Sebastian Zeissig, Richard S. Blumberg – FEBS Letters

“Here, we outline the mechanisms of bidirectional cross-talk between the microbiota and CD1d-restricted NKT cells and discuss how a perturbation of these processes can contribute to the pathogenesis of immune-mediated disorders at mucosal surfaces.”

Review/Book chapter Gastrointestinal microbiota – Katherine Stephens – Advanced Nutrition and Dietetics in Gastroenterology

“This chapter summarizes the functions of the human gastrointestinal tract. A main function of the GI microbiota is modulation of the immune system. The chapter focues on the factors influencing composition of the microbiota.”

Perturbation of the Human Microbiome as a Contributor to Inflammatory Bowel Disease – Bayan Missaghi – Pathogens

“This review presents an outline of the loss of a normal microbiome as an etiology of immune dysregulation and IBD pathogenesis initiation. “

37 People Want to Peer Inside Your Poop…You Know, for Science – Angus Chen – Discover Magazine

“Rob Knight, a microbiologist at the University of Colorado, Boulder, and his colleagues want poop from every person in America.”

Mediterranean Diet and Health: Food Effects on Gut Microbiota and Disease Control
Federica Del Chierico – International Journal of Molecular Sciences

“For this purpose, we present a study proposal relying on the generation of individual gut microbiota maps from MD-aware children/adolescents. “

Respiratory microbiome

Evidence that intraspecific trait variation among nasal bacteria shapes the distribution of Staphylococcus aureus – Ben Libberton – Infection and Immunity

“We characterised S. aureus growth inhibition by the culturable bacterial aerobe consortia of 60 nasal microbiomes, revealing intraspecific variation in growth inhibition and that inhibitory isolates clustered within communities that were culture-negative for S. aureus. “

Vaginal microbiome

Characterization of the vaginal microbiota of healthy Canadian women through the menstrual cycle – Bonnie Chaban – Microbiome

“Polymerase chain reaction (PCR) was performed to amplify the universal target region of the cpn60 gene and generate amplicons representative of the microbial community. Amplicons were pyrosequenced, assembled into operational taxonomic units, and analyzed. “

Pregnancy

The effects of designation and volume of neonatal care on mortality and morbidity outcomes of very preterm infants in England: retrospective population-based cohort study – SI Watson – BMJ Open

“High-volume neonatal care provided at the hospital of birth may protect against in-hospital mortality in very preterm infants. “

Understanding the Complexity of the Immune System during Pregnancy – Karen Racicot – American Journal of Reproductive Immunology

“In this review, we discuss our present understanding of the ‘immunity of pregnancy’ in the context of the response to cervical and placental infections and how these responses affect both the mother and the fetus.”

Animal models of human microbiota or disease

Galacto‐oligosaccharides attenuate renal injury with microbiota modification – Satoshi U. Furuse – Physiological Reports

“The microbiota analysis indicated that GOS significantly increased three bacterial families and decreased five families in the Nx rats. “

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Today we “Hover or Cover” the toilet seat, compare uBiome and American Gut results, and learn about bacterial diversity and stem cell transplants, breast milk microbiota, and culturomics.

Microbiome in the news

Here’s the poop on getting your gut microbiome analyzed – Tina Hesman Saey – ScienceNews

“When the second set of gut results came in, I was shocked. The results didn’t match at all with µBiome. “

WATCH: Is it OK to sit on a public toilet seat? – ScienceAlert

“It’s a dilemma we’ve all faced at some point: should you ever let your bum touch a public toilet seat? Thankfully Mitch and Greg from AsapSCIENCE have examined the evidence and come up with the (somewhat surprising) answer in their latest episode.”

Gut Reactions – Claudia Wallis – Scientific American

“Intestinal bacteria may help determine whether we are lean or obese”

10 Things You Need To Know About Your Microbiome – Raphael Kellman – MindBodyGreen

Pregnancy and Birth

Gut and Breast Milk Microbiota and Their Role in the Development of the Immune Function – Maria Elisabetta Baldassarre – Current Pediatrics Reports

“In newborns, the maternal gut microbiota may either come across into the amniotic fluid or secrete factors that enter the amniotic fluid and affect the development of oral tolerance in utero.”

Oral microbiome

Acquiring and maintaining a normal oral microbiome: current perspective
Egija Zaura – Frontiers in Cellular and Infection Microbiology

“In this review we present our hypothesis on how a healthy oral microbiome is acquired and maintained.”

Gut microbiome

The effects of intestinal tract bacterial diversity on mortality following allogeneic hematopoietic stem cell transplantation – Ying Taur – Blood

“Fecal specimens were collected from 80 recipients of allo-HSCT at the time of stem cell engraftment. Bacterial 16S rRNA gene sequences were characterized, and microbial diversity was estimated using the inverse Simpson index. “

Culturomics and pyrosequencing evidence of the reduction in gut microbiota diversity in patients with broad-spectrum antibiotics – Grégory Dubourg – International Journal of Antimicrobial Agents

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

Characterization of bacterial community shift in human Ulcerative Colitis
patients revealed by Illumina based 16S rRNA gene amplicon sequencing – Sandeep A Walujkar – Gut Pathogens

“Mucosal microbiota was analyzed by means of 16S rRNA gene-based Illumina high throughput sequencing. Quantitative real-time PCR (qPCR) was performed to determine total bacterial abundances.”

Keeping peace with the microbiome: acetate dampens inflammatory cytokine production in intestinal epithelial cells – Nicholas Arpaia – Immunology & Cell Biology

“In this issue, Ishiguro et al.2 show that the short-chain fatty acid (SCFA), acetate, produced during carbohydrate fermentation by commensal microorganisms in the cecum, is capable of dampening responses within intestinal epithelial cells (IEC), and functions by targeting the downstream signaling proteins that are activated on recognition of bacterial flagellin by TLR5”

Respiratory microbiome

A large genomic island allows Neisseria meningitidis to utilize propionic acid, with implications for colonisation of the human nasopharynx – Maria Chiara E. Catenazzi – Molecular Microbiology

“Here we identify a genomic island (the prp gene cluster) in N. meningitidis that enables this species to utilize propionic acid as a supplementary carbon source during growth, particularly under nutrient poor growth conditions. “

Animal and in vitro models of human microbiome

Observation of Inflammatory Responses in Mice Orally Fed with Bacteriophage T7 – Kwangseo Park – Journal of Applied Microbiology

“This study investigated the inflammatory responses in mice fed orally with bacteriophages. The mice were fed with either murine norovirus (MNV) or bacteriophage T7 for 10 days and then sacrificed. “

Development of an oral mucosa model to study host-microbiome interactions during wound healing – Tine De Ryck – Applied Microbiology and Biotechnology

“Microbiota derived from oral swabs were cultured on an agar/mucin layer and challenged with monolayers of keratinocytes grown on plastic or collagen type I layers embedded with fibroblasts.”

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