Category Archives: Infection and transplantation

General microbiology and science, August 14

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A metabolic map of Faecalibacterium prausnitzii, bacteria injections to cure cancer, a researcher smuggling live bacteria in a lunchbox,  and a scientist in trouble for posting a PhD thesis.

Metabolomics

Functional Metabolic Map of Faecalibacterium prausnitzii, a Beneficial Human Gut Microbe – Almut Heinken – Journal of Bacteriology

“In this study, we present an integrated, iterative approach of computational modeling, in vitro experiments, metabolomics, and genomic analysis to accelerate the identification of metabolic capabilities for poorly characterized (anaerobic) microorganisms.”

Transcriptomics

Pervasive transcription: illuminating the dark matter of bacterial transcriptomes – Joseph T. Wade & David C. Grainger – Nature Reviews Microbiology

“In this Opinion article, we discuss our current understanding of pervasive transcription, its genetic origin and its regulation. “

More microbiology

Intratumoral injection of Clostridium novyi-NT spores induces antitumor responses
Nicholas J. Roberts – Science Translational Medicine

“On the basis of these encouraging results, we treated a human patient who had an advanced leiomyosarcoma with an intratumoral injection of C. novyi-NT spores. This treatment reduced the tumor within and surrounding the bone. “

Canadian ex-researcher pleads guilty in attempted bacteria-smuggling case – Lee-Anne Goodman

“With his wife in the passenger seat, they discovered in his suitcase 17 vials of live Brucella — contained in a block of ice and swathed in bubble wrap in a children’s lunch bag — and a substantial quantity of goat’s blood.”

Techniques

Preprint: Swabs to Genomes: A Comprehensive Workflow – David A Coil – PeerJ

“The objective of the present study was to design, test, troubleshoot, and publish a simple, comprehensive workflow from the collection of an environmental sample (a swab) to a published microbial genome”

Accuracy of Next Generation Sequencing Platforms – Edward J Fox – Next Generation: Sequencing & Applications

“The ability of these technologies to disentangle sequence heterogeneity, however, is limited by their relatively high error rates”

Uniting the classification of cultured and uncultured bacteria and archaea using 16S rRNA gene sequences — Pablo Yarza – Nature Reviews Microbiology

“Our analyses show that only nearly complete 16S rRNA sequences give accurate measures of taxonomic diversity. In addition, our analyses suggest that most of the 16S rRNA sequences of the high taxa will be discovered in environmental surveys by the end of the current decade.”

Science, Publishing, Career

Financial costs and personal consequences of research misconduct resulting in retracted publications – Andrew M Stern, Arturo Casadevall, R Grant Steen, Ferric C Fang – eLife

“We found that papers retracted due to misconduct accounted for approximately $58 million in direct funding by the NIH between 1992 and 2012, less than 1% of the NIH budget over this period. ”

Student may be jailed for posting scientist’s thesis on web – David Reay – Nature News Blog

“Colombian biology student is facing up to 8 years in jail and a fine for sharing a thesis by another scientist on a social network. Diego Gómez Hoyos posted the 2006 work, about amphibian taxonomy, on Scribd in 2011.

Study: Uncivil work environment pushing women out of the engineering field – Brigid Schulte – Washington Post

“a new National Science Foundation report released on Saturday about why so few women go into engineering, or stay in the field, highlights a key reason: a workplace culture of incivility toward women.”

Science of inclusion – Holly McDede – SFBG.com

“As Big Tech struggles with diversity, women find support and fellowship in the biotech industry.”

Bik’s Picks

Pour on the Salt? New Research Suggests More Is OK – Judy Silverman and Lisa Tolin – NBC News

“New research suggests that healthy people can eat about twice the amount of salt that’s currently recommended — or about as much as most people consume anyway. “

At Harvard, tiny robots ‘swarm’ into shape – Carolyn Y. Johnson – Boston Globe

“When Harvard scientist Michael Rubenstein walks into the laboratory in the morning, he is greeted with a scene somewhere between a disco and the opening of a science fiction movie about a robot apocalypse. A constellation of LED lights blinks in the darkness — the electronic heartbeat of his 1,024-robot horde. They are ready to do his bidding.”

Newborns’ genetic code sends infection distress signal – Science Daily

“Babies suffering from life-threatening bacterial infections such as sepsis could benefit from improved treatment, thanks to a ground-breaking study. “

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Microbiome digest, August 13, 2014

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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. “

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General microbiology and science, August 11, 2014

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Single cell genomics, metagenomics and bioinformatics, primers for protozoa detection, and Bik’s Picks.
Microbial detection

Clinical PathoScope: rapid alignment and filtration for accurate pathogen identification in clinical samples using unassembled sequencing data – Allyson L Byrd – BMC Bioinformatics

“Clinical PathoScope is the only pathogen identification method currently available that can identify multiple pathogens from mixed samples and distinguish between very closely related species and strains in samples with very few reads per pathogen. “

Metagenomics

Recent advances in genomic DNA sequencing of microbial species from single cells – Roger S. Lasken & Jeffrey S. McLean – Nature Review Genetics

“With the advent of single-cell sequencing, genomes of uncultivated species are rapidly filling in unsequenced branches of the microbial phylogenetic tree.”

Employing whole genome mapping for optimal de novo assembly of bacterial genomes
Basil Britto Xavier – BMC Research Notes

“Utilising several assembly tools based on de Bruijn graphs like Velvet, SPAdes and IDBA, we demonstrate that at the optimal N50, mis-assemblies do occur, even when using the multi-k-mer approaches of SPAdes and IDBA. “

Protozoal components of microbiome

Design and Validation of Four New Primers for Next-Generation Sequencing To Target the 18S rRNA Genes of Gastrointestinal Ciliate Protozoa – Suzanne L. Ishaq and André-Denis G. Wright – Applied and Environmental Microbiology

“PCR amplicons of 394 to 498 bases were generated from three primer sets, sequenced using Roche 454 pyrosequencing with Titanium, and analyzed using the BLAST database (NCBI) and MOTHUR version 1.29.”

Microbes in the news

What Causes Antibiotic Resistance? Video Answers This In Awesome Animation – Kevin Wu – Inquisitr.com

“Kevin Wu details the evolution of this problem that present a big challenge for the future of medicine in this amazing animated video uploaded on YouTube.”

Women in Science

Harassment in Science, Replicated – Christie Aschwanden – The New York Times

“The findings are depressingly similar to the data some colleagues and I collected this year from an online questionnaire sent to science writers. “

Bik’s Picks

Comparative population genomics reveals the domestication history of the peach (Prunus persica) and human influences on perennial fruit crops – Ke Cao – Genome Biology

“We perform large-scale resequencing of 10 wild and 74 cultivated peach varieties, including 9 ornamental, 23 breeding, and 42 landrace lines. We identify 4.6 million SNPs, a large number of which could explain the phenotypic variation in cultivated peach.”

Grizzly bears master healthy obesity – Meghan Rosen – Science News

“Though the animals beef up before hibernating, they may avoid diabetes by tweaking signals in fat cells, researchers report in the Aug. 5 Cell Metabolism.”

Natural light in office boosts health – Science Daily

“Office workers with more natural light exposure at the office had longer sleep duration, better sleep quality, more physical activity and better quality of life compared to office workers with less light exposure in the workplace, a study shows.”

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Human microbiome, August 11, 2014

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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. “

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Microbiome Digest, August 1, 2014

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Microbiome composition and vaccine response or chemotherapy, cassava beer, two nice articles about metagenomics tools and contamination, and the weekend picks.

Human gut microbiome

Stool Microbiota and Vaccine Responses of Infants – M. Nazmul Huda – Pediatrics

“Actinobacteria abundance was positively associated with T-cell responses to BCG, OPV, and TT; with the delayed-type hypersensitivity response; with immunoglobulin G responses; and with TI. B longum subspecies infantis correlated positively with TI and several vaccine responses. “

Systematic review: the role of the gut microbiota in chemotherapy- or radiation-induced gastrointestinal mucositis – current evidence and potential clinical applications – Y. Touchefeu – Alimentary Pharmacology & Therapeutics

“Search of the literature published in English using Medline, Scopus and the Cochrane Library, with main search terms ‘intestinal microbiota’, ‘bacteremia’, ‘mucositis’, ‘chemotherapy-induced diarrhoea’, ‘chemotherapy-induced mucositis’, ‘radiotherapy-induced mucositis’.”

Food microbiology

Local 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. “

Microbes in the News

It’s a bit – eh – graphic, but a nice overview of science and the people working in this field. I wish it would have contained a couple of pictures of non-pregnant women though. It feels as if we are only a vessel:  The Body’s Ecosystem – The Scientist

“Research on the human microbiome is booming, and scientists have moved from simply taking stock of gut flora to understanding the influence of microbes throughout the body.”

‘I’m not fat, it’s viral’ – Phage found in gut bacteria may aid obesity – Dan Stanton 0 Biopharma Reporter

“A newly discovered virus which infects intestinal bacteria might be a cause of obesity, but could increasing interest in bacteriophages drive new personalised medicines and alternatives to antibiotics?”

Diet Must be Different for Men and Women: Study – Soumo Ghosh – International Business Times

“The researchers found that the microscopic bacteria, or other such organism housed inside the human stomach are different in the case of men and women. Hence, they believe that the same diet for both may not have the same effect in them.”

Metabolomics

Emergent Biosynthetic Capacity in Simple Microbial Communities – Hsuan-Chao Chiu – PLOS Computational Biology

“Here we present a comprehensive computational framework, integrating high-quality metabolic models of multiple species, temporal dynamics, and flux variability analysis, to study the metabolic capacity and dynamics of simple two-species microbial ecosystems.”

Metagenomics

Metagenomics Mash-Up – Kelly Rae Chi – The Scientist

“The Scientist spoke with developers of tools for parsing genomic data from diverse communities of microorganisms. Here are some of the newest strategies and programs for taxonomic, functional, and comparative analyses.”

Microbial detection

Who are the contaminants in your sequencing project? – Jonathan Eisen – MicrobeNet

“Such amplification is alas pretty common – due to contamination occurring in some other material added to the PCR reaction. “

Science and publishing

The Self-Edited Woman – Paige Brown – SciLogs International

“Un-prompted, several young female science bloggers I’ve interviewed mention having blogged anonymously in the past, being self-conscious about expressing their expertise on a topic, or avoiding certain topics because of the nasty comments they might receive. “

Bik’s Picks

We have the science to build an Ebola vaccine. So why hasn’t it happened? – Sarah Kliff – Vox

“This isn’t how an Ebola outbreak has to work. Researchers have devoted lots of time to building a vaccine that could stop the disease altogether — and according to Daniel Bausch, a Tulane professor who researches Ebola and other infectious diseases, they’re making really significant progress.”

Littering and Following the Crowd – Vivian Wagner – The Atlantic

“Why it’s so tempting to throw trash on the ground, and how environmentalists are using psychology to change that”

F.D.A. Acts on Lab Tests Developed In-House – Andrew Pollack – The New York Times

“The Food and Drug Administration announced on Thursday that it would start regulating medical laboratory testing, saying that tests used to make important treatment decisions must be vetted and validated before they go into use.”

Grad Student Freed By Police After Three Years Trapped In The Same Experiment – The Allium

“He is thought to have survived by eating printouts of PloS One papers and drinking his own tears.”

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General microbiology and science

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Some new bioinformatic tools,  dengue response and vaccines, and host response and transcriptomics.

Host response and gene expression

Single-cell RNA-seq: advances and future challenges – Antoine-Emmanuel Saliba – Nucleic Acids Research

“Different single-cell RNA-seq protocols have been introduced and are reviewed here—each one with its own strengths and current limitations.”

Corset: enabling differential gene expression analysis for de novo assembled transcriptomes – Nadia M Davidson and Alicia Oshlack – Genome Biology

“Here we present Corset, a method that hierarchically clusters contigs using shared reads and expression, then summarizes read counts to clusters, ready for statistical testing. Using a range of metrics, we demonstrate that Corset out-performs alternative methods.”

Bioinformatics

Suffix tree searcher: exploration of common substrings in large DNA sequence sets
David Minkley – BMC Research Notes

“The program accommodates very large numbers of very large sequences, with aggregate size reaching tens of billions of nucleotides. The program makes use of pre-sorted persistent “building blocks” to reduce the time required to construct new trees.”

SnipViz: a compact and lightweight web site widget for display and dissemination of multiple versions of gene and protein sequences – Daniel Jaschob – BMC Research Notes

“SnipViz is a client-side software tool designed to disseminate multiple versions of related gene and protein sequences on web sites. SnipViz has a space-efficient, interactive, and dynamic interface for navigating, analyzing and visualizing sequence data.”

Dengue

 

Dengue vaccine trial poses public health quandary – Dennis Normile – Science

 

“The vaccine, developed by Sanofi Pasteur, proved safe, had an overall efficacy rate of 56.5%, and reduced cases of severe disease by 88.5%. But it had limited efficacy against dengue 2, one of four dengue virus serotypes in circulation.”

Predictors of hospital stay and mortality in dengue virus infection-experience from Aga Khan University Hospital Pakistan – Muhammad Abdul Khalil – BMC Research Notes

“Increasing age, coagulopathy and acute kidney injury in patients with DVI is associated with increased hospital stay.”

 

 

Science and publishing

A crisis of trust – Pubpeer

“As PubPeer developed, and especially once we enabled anonymous posting, we were shocked at the number of comments pointing out much more fundamental problems in papers, involving very questionable research practices and rather obvious misconduct. “

Dr. Bik’s Picks

Note to Science: The GOP’s Just Not That That Into You – Jeffrey Kluger – Time

“If the Speaker, by his own admission, isn’t qualified to debate climate change, fine, he’s excused from the conversation—and he should be expected not to offer further opinion on the matter. “

The first Science Hack Day in China – Ariel Waldman – BoingBoing

“Over the course of the weekend in a Shanghai incubator space, kids, parents, scientists, artists and technologists joined forces to play with science and prototype ideas. “

Exclusive: Naked Mole Rat Filled With Regret Over Evolutionary Choices – The Allium

“In an exclusive interview with The Allium, the Naked Mole Rat has revealed its regret at some of the evolutionary choices it has made, in particular the whole nakedness and the teeth.”

 

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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 23

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

General microbiome

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

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

Human gut microbiome

Nan Qin Nature GutAlterations of the human gut microbiome in liver cirrhosis – Nan Qin – Nature

“Here we characterize the gut microbiome in liver cirrhosis by comparing 98 patients and 83 healthy control individuals… Most (54%) of the patient-enriched, taxonomically assigned species are of buccal origin, suggesting an invasion of the gut from the mouth in liver cirrhosis. “

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

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

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

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

General Microbiology

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

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

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

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

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

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

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

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

Dengue

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

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

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

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

Dr. Bik’s Picks

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

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

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

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

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

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

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Human microbiome, July 22

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Transcriptome in periodontitis, metabolomic analysis of breath in IBD patients, cystic fibrosis microbiome, and Clostridium difficile.

Human microbiome general

Review: Deciphering the tête-à-tête between the microbiota and the immune system – Neeraj K. Surana and Dennis L. Kasper – Journal of Clinical Investigation

“In this Review, we discuss the current state of knowledge regarding the role of the intestinal microbiota in immunologic development, highlighting mechanistic principles that can guide future work.”

Meeting report: Human microbiome science: vision for the future, Bethesda, MD, July 24 to 26, 2013 – Jacques Ravel and many others – Microbiome

“This report summarizes the presentations but also describes what is needed for human microbiome research to move forward and deliver medical translational applications.”

Metabolomics

Metabolomic analysis of breath volatile organic compounds reveals unique breathprints in children with inflammatory bowel disease: a pilot study – N. Patel – Alimentary Pharmacology & Therapeutics

“Exhaled breath was collected and analysed using a selective ion flow tube mass spectroscopy (SIFT-MS) to identify new markers or patterns of IBD.”

Metabolites related to gut bacterial metabolism, peroxisome proliferator-activated receptor-alpha activation, and insulin sensitivity are associated with physical function in functionally-limited older adults – Michael S. Lustgarten – Aging Cell

“Collectively, these data suggest that gut microbial metabolism, PPAR-α activation, and insulin sensitivity may be involved in mechanisms that underlie physical function in functionally-limited older adults.”

Oral microbiome

Community-wide transcriptome of the oral microbiome in subjects with and without periodontitis – Ana E Duran-Pinedo – ISME J

“We report here the in situ genome-wide transcriptome of the subgingival microbiome in six periodontally healthy individuals and seven individuals with periodontitis.”

Respiratory microbiome

Predominant pathogen competition and core microbiota divergence in chronic airway infection – Geraint B Rogers – ISME Journal

“..we analysed 16S rRNA gene pyrosequencing data generated previously from 60 adult bronchiectasis patients, whose airway microbiota was dominated by either P. aeruginosa or H. influenzae.”

Pyrosequencing reveals transient cystic fibrosis lung microbiome changes with intravenous antibiotics – Daniel J. Smith – European Respiratory Journal

“Microbial community profiles were derived through analysis of bacterial-derived 16S ribosomal RNA by pyrosequencing and changes over time were compared.”

Review: Respiratory microbiota: addressing clinical questions, informing clinical practice – Geraint B Rogers – Thorax

“In this article, we set out the key principles underpinning microbiota research in respiratory contexts and provide practical guidance on how best such studies can be designed, executed and interpreted. “

Propionibacterium-Produced Coproporphyrin III Induces Staphylococcus aureus Aggregation and Biofilm Formation – Michael S. Wollenberg – mBio

“We observed that crude extracts of cell-free conditioned medium from Propionibacterium spp. induce S. aureus aggregation in culture. “

Gut microbiome

Reset of a critically disturbed microbial ecosystem: faecal transplant in recurrent Clostridium difficile infection – Susana Fuentes – ISME Journal

“Global composition and network analysis of the microbiota was performed in faecal samples from nine patients with recurrent CDI. Analyses were performed before and after duodenal donor faeces infusion, and during a follow-up of 10 weeks. The microbiota data were compared with that of the healthy donors. “

Review: Clostridium difficile and the microbiota – Anna M. Seekatz and Vincent B. Young – Journal of Clinical Investigation

“Both human and animal models have demonstrated the importance of the gut microbiota’s capability of providing colonization resistance against C. difficile.”

Vaginal microbiome

Primate vaginal microbiomes exhibit species specificity without universal Lactobacillus dominance – Suleyman Yildirim – ISME Journal

“We conducted comparative analyses of the primate vaginal microbiome using pyrosequencing of the 16S rRNA genes of a phylogenetically broad range of primates to test for factors affecting the diversity of primate vaginal ecosystems. … humans were distinct from other primates in both microbiome composition and diversity.“

Semen microbiome

The Semen Microbiome and Its Relationship with Local Immunology and Viral Load in HIV Infection – Cindy M. Liu – PLOS Pathogens

“HIV infection was associated with decreased semen microbiome diversity and richness, which were restored after six months of ART.”

Antibiotic perturbation and microbiome

Bacteria, phages and pigs: the effects of in-feed antibiotics on the microbiome at different gut locations – Torey Looft – ISME Journal

“In this study, we defined the lumenal and mucosal bacterial communities from the small intestine (ileum) and large intestine (cecum and colon) plus feces, and characterized the effects of in-feed antibiotics (chlortetracycline, sulfamethazine and penicillin (ASP250)) on these communities. “

Impact of Antibiotics on the Intestinal Microbiota and on the Treatment of Shiga-toxin-Producing Escherichia coli and Salmonella Infections – Szych, Jolanta – Current Pharmaceutical Design

“This review evaluates the current literature based on the impact of antibiotics on the intestinal microbiota and the critical role of intestinal bacteria in controlling infection and subsequent clinical disease caused by STEC and Salmonella, and the transmissibility of these important pathogens”

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Human microbiome digest, July 21

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

General microbiome

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

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

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

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

40 under 40: Rob Knight – Cell

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

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

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

Oral microbiome

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

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

Skin microbiome

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

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

Gastric microbiome

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

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

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

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

Gut microbiome

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

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

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

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

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

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

 

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