Human microbiome, July 28

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 and general science digest, July 10

Hi all, just one post today, with everything combined. Bacterial vaginosis, daily rhythms  of marine bacteria, food microbiology, and The Picks.

Human vaginal microbiome

Role of Gardnerella vaginalis in the Pathogenesis of Bacterial Vaginosis: A Conceptual Model – Jane R. Schwebke – Journal of Infectious Diseases

“Our model suggests that BV is initiated by the sexual transmission of Gardnerella vaginalis, which has the appropriate virulence factors to adhere to host epithelium, create a biofilm community, and successfully compete with lactobacilli for dominance in the vaginal environment. “

Seawater microbiome

Multispecies dielMultispecies diel transcriptional oscillations in open ocean heterotrophic bacterial assemblages – Elizabeth A. Ottesen – Science, with an Editorial by E. Virginia Armbrust: “Taking the pulse of ocean microbes

“As anticipated, the cyanobacterial transcriptome exhibited pronounced diel periodicity. Unexpectedly, several different heterotrophic bacterioplankton groups also displayed diel cycling in many of their gene transcripts. “

Screen Shot 2014-07-10 at 11.53.04 PMReview: Bacterial diversity and antibiotic resistance in water habitats: searching the links with the human microbiome – Ivone Vaz-Moreira – FEMS Microbiology Reviews

“In this review, the hypothesis that some bacteria may share different water compartments and be also hosted by humans is discussed based on the comparison of the bacterial diversity in different types of water and with the human-associated microbiome. “

Food microbiology

Cassava beerLocal domestication of lactic acid bacteria via cassava beer fermentation – Alese M. Colehour – PeerJ

“Bacteria responsible for chicha fermentation could be a source of microbes for the human microbiome, but little is known regarding the microbiology of chicha. We investigated bacterial community composition of chicha batches using Illumina high-throughput sequencing. “

LobsterCharacterization of the dominant bacterial communities during storage of Norway lobster and Norway lobster tails (Nephrops norvegicus) based on 16S rDNA analysis by PCR-DGGE – Bekaert Karen – Food Microbiology

“To characterize as many bacterial species present as possible, we performed advanced molecular identification techniques (PCR-DGGE). The initial TVC of fresh Norway lobster meat was high (3.0 log cfu/g) as compared to fish.”

charquiEffect of autochthonous bacteriocin-producing Lactococcus lactis on bacterial population dynamics and growth of halotolerant bacteria in Brazilian charqui – Vanessa Biscola – Food Microbiology

“Charqui is a fermented, salted and sun-dried meat product, widely consumed in Brazil and exported to several countries. “

Microbes in the news

Using the gut microbiome to improve health – Mary MacVean – LA Times

“The “bistable” groups, the authors wrote, represent “tipping elements,” or components of the gut microbes that “exhibit alternative stable states linked to the overall ecosystem state and our physiology.” “

Science, Ethics and Publishing

Crack Down on Scientific Fraudsters – Adam Marcus and Ivan Oransky – New York Times

“Criminal charges against scientists who commit fraud are even more uncommon. In fact, according to a study published last year, “most investigators who engage in wrongdoing, even serious wrongdoing, continue to conduct research at their institutions.””

Dr. Bik’s Picks

Microplastics in the seas – Kara Lavender Law, Richard C. Thompson – Science

“Microplastics are likely the most numerically abundant items of plastic debris in the ocean today, and quantities will inevitably increase, in part because large, single plastic items ultimately degrade into millions of microplastic pieces. “

Uncontacted tribe in Brazil emerges from isolation – Heather Pringle – Science

“The meeting was Brazil’s first official contact with an isolated Amazonian tribe in 20 years. Anthropologists remain deeply concerned about the tribe’s future as it encounters novel diseases and resource-hungry outsiders. “

Polar BearsPolar Bears from Space: Assessing Satellite Imagery as a Tool to Track Arctic Wildlife – Seth Stapleton – PLOS ONE

“We examined satellite images of a small island in Foxe Basin, Canada, occupied by a high density of bears during the summer ice-free season. Bears were distinguished from other light-colored spots by comparing images collected on different dates. “

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