Tag Archives: helminths

Microbiome Digest, October 29, 2014

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The genome of Mycoplasma Mnola, helminths in wild rats, fungi in strawberry roots, and the top 100 most cited papers of all time. Can you guess which one is #1?

Human genital microbiome

An Emerging Mycoplasma Associated with Trichomoniasis, Vaginal Infection and Disease – Jennifer M. Fettweis – PLOS ONE

“In this study, the mycoplasma was found almost exclusively in women infected with the sexually transmitted pathogen Trichomonas vaginalis, but rarely observed in women with no diagnosed disease.”

Human gut microbiome

Bacteriology and Changes in Antibiotic Susceptibility in Adults with Community-Acquired Perforated Appendicitis – Hong Gil Jeon – PLOS ONE

“We retrospectively reviewed records of adult patients diagnosed with perforated appendicitis at an 800-bed teaching hospital between January 2000 and December 2011. “

Animal microbiome

Changes in the intestinal bacterial community during the growth of white shrimp, Litopenaeus vannamei – Zhaobin Huang – Aquaculture Research

“In this study, we documented the changes in the intestinal bacterial community at four stages in Litopenaeus vannamei…, using 454 pyrosequencing techniques. “

* Assessment of Helminth Biodiversity in Wild Rats Using 18S rDNA Based Metagenomics – Ryusei Tanaka – PLOS ONE

“In this study, we assessed parasite diversity in wild rats using 18S rDNA-based metagenomics. 18S rDNA PCR products were sequenced using an Illumina MiSeq sequencer and the analysis of the sequences using the QIIME software successfully classified them into several parasite groups.”

Soil microbiome

Linking soil microbial communities to vascular plant abundance along a climate gradient – Luca Bragazza – New Phytologist

“Microbial community structure and function were measured seasonally in four peatlands located along an altitude gradient representing a natural gradient of climate and associated vascular plant abundance.”

* Influence of Soil Type, Cultivar and Verticillium dahliae on the Structure of the Root and Rhizosphere Soil Fungal Microbiome of Strawberry – Srivathsa Nallanchakravarthula – PLOS ONE

“In this study we examined the effects of different soils and cultivars, and the presence of a soil-borne fungal pathogen, Verticillium dahliae, on the fungal microbiome of the rhizosphere soil and roots of strawberry plants, using high-throughput pyrosequencing.”

Metagenomics / Bioinformatics

* Evaluation of a Hybrid Approach Using UBLAST and BLASTX for Metagenomic Sequences Annotation of Specific Functional Genes – Ying Yang – PLOS ONE

“A hybrid annotation pipeline proposed previously for taxonomic assignments was evaluated in this study for metagenomic sequences annotation of specific functional genes, such as antibiotic resistance genes, arsenic resistance genes and key genes in nitrogen metabolism. “

Metabolomics

Long-term phenotypic evolution of bacteria – Germán Plata – Nature

“Here we perform a comparative analysis of bacterial growth and gene deletion phenotypes using hundreds of genome-scale metabolic models. “

Phages and viruses

Conditional tolerance of temperate phages via transcription-dependent CRISPR-Cas targeting – Gregory W. Goldberg – Nature

“Here we show that the Staphylococcus epidermidis CRISPR-Cas system can prevent lytic infection but tolerate lysogenization by temperate phages. “

Science, publishing and career

The top 100 papers – Richard Van Noorden – Nature

“To mark the anniversary, Nature asked Thomson Reuters, which now owns the SCI, to list the 100 most highly cited papers of all time.”

Bibliometrics: Is your most cited work your best? – John P. A. Ioannidis – Nature

“John P. A. Ioannidis and colleagues asked the most highly cited biomedical scientists to score their top-ten papers in six ways.”

Recommendations for the Role of Publishers in Access to Data – Jennifer Lin, Carly Strasser – PLOS Biology

“As appeals for public access of research data continue to proliferate, many scholarly publishers—alongside funders, institutions, and libraries—are expanding their role to address this need. “

How to Make More Published Research True – John P. A. Ioannidis – PLOS ONE

“Currently, many published research findings are false or exaggerated, and an estimated 85% of research resources are wasted.”

* Prominent Geomicrobiologist Dies – Tracy Vence – The Scientist

“Katrina Edwards, whose research focus was on discovering life beneath the ocean floor, has passed away at age 46.”

Bik’s Picks

* The Art of Science: Popsicles Go Viral – The Finch and Pea

“Lick a virus? Probably not a good idea, unless it’s a Dangerous Popsicle, a sweet treat created by artist and designer Wei Li. “

Dozens of genes associated with autism in new research – Science Direct

“Two major genetic studies of autism, involving more than 50 laboratories worldwide, have newly implicated dozens of genes in the disorder. “

Antares Rocket Explosion Destroyed These Kids’ Science Projects – Rheana Murray – ABC News

“Students across the nation watched their science projects go up in flames as the rocket bound for the International Space Station exploded moments after takeoff.”

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Microbiome Digest, October 9, 2014

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Human microbiome general

Advancing the Microbiome Research Community – Curtis Huttenhower – Cell

“We outline opportunities in interdisciplinary research, analytical rigor, standardization, and policy development for this relatively new and rapidly developing field. “

Human oral microbiome

Bioinformatic investigation of the cost management strategies of five oral microbes – K.J. Cross – Molecular Oral Microbiology

“The aim of this study was to investigate if five oral bacterial species implement cost management strategies to reduce the energy burden of extracellular unrecyclable proteins.”

Human skin microbiome

Identification of molecular mechanisms used by Finegoldia magna to penetrate and colonize human skin – Elizabeth C. Murphy – Molecular Microbiology

“This study examines the molecular mechanisms F. magna uses when colonizing or establishing an infection in the skin. “

Human gut microbiome

Bacterial ClpB heat-shock protein, an antigen-mimetic of the anorexigenic peptide α-MSH, at the origin of eating disorders – N Tennoune – Translational Psychiatry

“Here, using proteomics, we identified ClpB heat-shock disaggregation chaperone protein of commensal gut bacteria Escherichia coli as a conformational antigen mimetic of α-MSH.”

Animal models of microbiome research

Effects of essential oil supplementation of a low-energy diet on performance, intestinal morphology and microflora, immune properties and antioxidant activities in weaned pigs – Zhikai Zeng – Animal Science Journal

Soil microbiome

Poster presentation: Starting study of microbial genetics diversity in soils of mangrove preserved in sergipe – Karla Cristina Santos Freire – BMC Proceedings

“This paper proposes the characterization and evaluation of structures and diversity of microbial communities in the soil of mangroves in three conservation areas located in Sergipe.“

Community assembly of ectomycorrhizal fungi along a subtropical secondary forest succession – Cheng Gao – New Phytologist

“We examined the communities of ectomycorrhizal (EM) fungi in young, intermediate and old forests in a Chinese subtropical ecosystem, using 454 pyrosequencing”

Metagenomics / Bioinformatics

Functional phylogenomics analysis of bacteria and archaea using consistent genome annotation with UniFam – Juanjuan Chai – BMC Evolutionary Biology

“A total of 14,727 GenBank prokaryotic genomes were re-annotated using a new protein family database, UniFam, to obtain consistent functional annotations for accurate comparison. “

More Microbiology

Halting harmful helminths – Karl F. Hoffmann, Paul J. Brindley, Matthew Berriman – Science

“More than 300 million people are infected each year with parasitic flatworms such as hydatid tapeworms and blood fluke schistosomes. “

Chromosome position effects on gene expression in Escherichia coli K-12 – Jack A. Bryant – Nucleic Acids Research

“Here, using Escherichia coli K-12, we demonstrate that expression of a reporter gene cassette, comprised of the model E. coli lac promoter driving expression of gfp, varies by ∼300-fold depending on its precise position on the chromosome. “

Microbes in the news

‘Good Poop’ Diet Is the Next Big Thing – Daniela Drake – The Daily Beast

“Now a new book, The Skinny Gut Diet, by nutritionist Brenda Watson, tracks the progress of people who follow a diet specifically designed to alter the gut microbiome. “

Another probiotic advantage: Bacteria protects against heavy metal poisoning – Jim Algar – Tech Times

“Probiotic bacteria found in yogurt can protect people from the effects of exposure to heavy metals, particularly in pregnant women and children, a Canadian study suggests.”

Science, publishing, career

The scientists who get credit for peer review – Richard Van Noorden – Nature

“Publons rewards researchers for putting their peer-review activity online. Nature spoke to the startup’s co-founder and two super-users.”

Meet the New Underclass: People With Ph.D.s in Science – Mark Strauss – iO9

“Once upon a time, newly-minted science Ph.D.s would get research jobs at a senior scientist’s laboratory, to train and hone the ideas they would explore at their own labs. But now the supply of post-doctoral students is outpacing demand, creating a new, hyper-educated underclass.”

Glut of postdoc researchers stirs quiet crisis in science –  Carolyn Y. Johnson – Boston Globe

Japan’s Missing Female Scientists – Jack Grove – Times Higher Education

“Too many female scientists are leaving Japan because they do not feel they can get ahead in its “male-dominated” society, a senior university leader has said.”

Bik’s Picks

Cave paintings change ideas about the origin of art – Pallab Ghosh – BBC

“Researchers tell the journal Nature that the Indonesian discovery transforms ideas about how humans first developed the ability to produce art.”

A timeline of a baby’s first hour – Laura Sanders – Science News

Fired science teacher did not have state license – 9 News

“The teacher fired after his science experiment injured four students, one seriously, did not have a valid Colorado teacher’s license.”

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Microbiome digest, July 31

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A snapshot of the human microbiome, a robot helping the Knight lab process samples (I want one!), and finally something that does NOT involve the microbiome.

Human microbiome general

SnapShot: The Human Microbiome – Antonio González – Cell

“This SnapShot presents several aspects of the human microbiome, including the characterization of the microbial species populating different body sites, the distribution of microbes across different geographic locations, and how the microbiome can be altered by a physiological process, exemplified by pregnancy.”

 

Animal models of microbiome

Symbiotic Bacterial Metabolites Regulate Gastrointestinal Barrier Function via the Xenobiotic Sensor PXR and Toll-like Receptor 4 – Madhukumar Venkatesh – Immunity

“Here we showed that microbial-specific indoles regulated intestinal barrier function through the xenobiotic sensor, pregnane X receptor (PXR).”

Bacterial Sensor Nod2 Prevents Inflammation of the Small Intestine by Restricting the Expansion of the Commensal Bacteroides vulgatus – Deepshika Ramanan – Immunity

“Here, we identified several abnormalities in the small-intestinal epithelium of Nod2−/− mice including inflammatory gene expression and goblet cell dysfunction, which were associated with excess interferon-γ production by intraepithelial lymphocytes and Myd88 activity.”

Effect of virgin and refined olive oil consumption on gut microbiota. Comparison to butter – M. Hidalgo – Food Research International

“Evolution of symbiont population in feces was studied using culture-dependent and culture-independent methods. In the latter, the V3 region of 16S rDNA was amplified and separated by Denaturing Gradient Gel Electrophoresis; followed by sequencing of the most representative bands. “

Animal gut microbiome

Longitudinal shifts in bacterial diversity and fermentation pattern in the rumen of steers grazing wheat pasture – D.W. Pitta – Anaerobe

“Rumen samples were collected on days 14, 28, 56 and 76, separated into solid and liquid fractions and analyzed for bacterial diversity using 16S pyrotag technology. “

Metabolomics

The cross talk between microbiota and the immune system: metabolites take center stage – Hagit Shapiro – Current Opinion in Immunology

“While most attention has focused on the innate recognition of immune-stimulatory bacterial molecules, such as cell wall components and nucleic acids, we emphasize here the impact of diet-dependent microbial metabolites on the development and function of the immune system.”

Bioinformatics tools

eSNaPD: A Versatile, Web-Based Bioinformatics Platform for Surveying and Mining Natural Product Biosynthetic Diversity from Metagenomes – Boojala Vijay B. Reddy – Chemistry & Biology

“Environmental Surveyor of Natural Product Diversity (eSNaPD) is a web-based bioinformatics and data aggregation platform that aids in the discovery of gene clusters encoding both novel natural products and new congeners of medicinally relevant natural products using (meta)genomic sequence data. “

RAMICS: trainable, high-speed and biologically relevant alignment of high-throughput sequencing reads to coding DNA – Imogen A. Wright and Simon A. Travers

“To facilitate such analyses, we have developed a novel tool, RAMICS, that is tailored to mapping large numbers of sequence reads to short lengths (<10 000 bp) of coding DNA”

Computational integration of genomic traits into 16S rDNA microbiota sequencing studies – Alexander Keller – Gene

“Here, we show in a proof-of-concept that computational approaches are able to retain functional information about microbial communities assessed through 16S rDNA (meta)barcoding by referring to reference genomes.”

Viruses and helminths

How helminths go viral – Rick M Maizels1, William C Gause

“On pages 573 and 578 of this issue, Reese et al. (3) and Osborne et al. (4), respectively, provide fine detail on how helminth worms can substantially enhance and reactivate viral infection, with major health implications for tropical medicine.”

Helminth infection reactivates latent γ-herpesvirus via cytokine competition at a viral promoter – T. A. Reese – Science

“We found that helminth infection, characterized by the induction of the cytokine interleukin-4 (IL-4) and the activation of the transcription factor Stat6, reactivated murine γ-herpesvirus infection in vivo.”

Virus-helminth coinfection reveals a microbiota-independent mechanism of immunomodulation – Lisa C. Osborne – Science

“Helminth coinfection resulted in impaired antiviral immunity and was associated with changes in the microbiota and STAT6-dependent helminth-induced alternative activation of macrophages. “

More Microbiology

Larger Mammalian Body Size Leads to Lower Retroviral Activity – Aris Katzourakis – PLOS Pathogens

“Body size explains 37% of the variance in ERV integration rate over the last 10 million years, controlling for the effect of confounding due to other life history traits. “

Microbes in the news

Researcher: Bacteria Ate Some Gulf Spill Toxins, but Worst Remain – Sandy Smith – EHS Today

“In two new studies conducted in a deep sea plume, Assistant Professor Olivia Mason found a species of bacteria called Colwellia likely consumed gaseous hydrocarbons and perhaps benzene, toluene, ethylbenzene and xylene compounds that were released as part of the oil spill. “

Baxter breaks out – Hal Hodson – New Scientist
http://www.sciencedirect.com/science/article/pii/S0262407914614342

“Baxter is even turning its grippers to lab work. Correll is working with UCB’s Rob Knight to teach Baxter the job of preparing faeces samples for research.”

Science and Career

The stressed-out postdoc – Carrie Arnold – Science

“After he defended his dissertation and moved to a new lab for his postdoc, Ian Street hoped his battles with anxiety and depression were over.”

Bik’s Picks

Africa Needs Science, Not Aid – Nkem Khumbah and Melvin P. Foote –  The New York Times

“Scientific and technological advancement will help eradicate poverty and promote homegrown economic development by providing Africa with the tools to address its own challenges and expand its industrial productivity. “

DDT Linked To Obesity In Female Mice Long After Exposure – Hank Campbell – Science 2.0

“A new epidemiology paper in PLOS One doesn’t try to prove that, the authors instead correlate DDT use from generations ago with increased waistlines of today.  DDT exposure may have made you fat, they conclude.”

 

A Lick Of The Tongue Changes This Ice Cream’s Color – Loren Grush – Popular Science

“The result was Xamaleón, which is Spanish for “chameleon.” With a patent pending, Linares is staying tight-lipped on the recipe, but apparently there’s a special ingredient dubbed the “love elixir,” which must be spritzed on the ice cream before it’s eaten. “

 

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Scientists explain mystery of our ‘lemon Moon’ – James Vincent – The Independent

“A new accurate map of the Moon has shown that it bulges slightly at one side and is flattened at the top and bottom – but how did it get this way?”

 

 

 

General microbiology and science, July 18

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Talking to bacteria to make them feel more comfortable (Bacteria whisperers!), probiotics, viruses vs. helminths, and women in Science.

Phages, viruses, helminths

Virus-helminth coinfection reveals a microbiota-independent mechanism of immunomodulation – Lisa C. Osborne – Science

“Helminth coinfection resulted in impaired antiviral immunity and was associated with changes in the microbiota and STAT6-dependent helminth-induced alternative activation of macrophages.”

Probiotics

Lactobacillus rhamnosus L34 and Lactobacillus casei L39 suppress Clostridium difficile-induced IL-8 production by colonic epithelial cells – Prapaporn Boonma – BMC Microbiology

“We screened Lactobacillus conditioned media from 34 infant fecal isolates for the ability to suppress C. difficile-induced IL-8 production from HT-29 cells. Factors produced by two vancomycin-resistant lactobacilli, L. rhamnosus L34 (LR-L34) and L.casei L39 (LC-L39), suppressed the secretion and transcription of IL-8 without inhibiting C. difficile viability or toxin production. “

Cross-talk between probiotic lactobacilli and host immune system – T.S. Kemgang – Journal of Applied Microbiology

“This review summarizes the interplay existing between the host immune system and probiotic lactobacilli, that is, with emphasis on lactobacilli as a prototype probiotic genus.”

General microbiology

Talking to bacteria? Towards light-mediated sensing of bacterial comfort – G. Zafrilla – Letters in Applied Microbiology

“The framework is to convert the human voice into electric pulses, these into light pulses exciting bacterial fluorescent proteins, and convert light-emission back into electric pulses, which will be finally transformed into synthetic voice messages.”

Bacteria in the news

More Forgotten Virus, Bacteria Vials Found at Federal Lab – Newsplex.com

“Food and Drug Administration officials said Wednesday the undocumented collection contained 327 carefully packaged vials, listing pathogens like dengue, influenza and rickettsia.”

1 weird tip to not die of smallpox – Beth Skwarecki – PLOS Blogs

“Jenner then attempted to infect the child with smallpox twenty more times in his life. Fortunately for the kid, the vaccine had worked.”

Women in Science

Science Has a Gender Problem. Science Just Made It Worse – Katy Waldman – Slate

“Transgender sex workers should not be expected to thank Science for “raising awareness” of them as erotic objects, jokes, or disease vectors. “

Survey of Academic Field Experiences (SAFE): Trainees Report Harassment and Assault – Kathryn B. H. Clancy – PLOS ONE

“Little is known about the climate of the scientific fieldwork setting as it relates to gendered experiences, sexual harassment, and sexual assault. We conducted an internet-based survey of field scientists (N = 666) to characterize these experiences. “

Dr. Bik’s Picks

Long read: One of a kind: What do you do if your child has a condition that is new to science? – Seth Mnookin – The New Yorker

“At first, they said, he seemed to represent a challenging problem for each new specialist to solve. But, as one conjecture after another was proved wrong, the specialists lost interest; many then insisted that the cause of Bertrand’s illness lay in someone else’s area of expertise. “

Introduction to special issue: Slicing the wheat genome – Kellye Eversole – Science

“Together, these Research Articles explore multiple dimensions of the 17-gigabase wheat genome and pave the way toward achieving a full reference sequence to underpin wheat research and breeding”

 

Earth-like soils on Mars? Ancient fossilized soils potentially found deep inside impact crater suggest microbial life – Science Daily

“Soil deep in a crater dating to some 3.7 billion years ago contains evidence that Mars was once much warmer and wetter, says a geologist based on images and data captured by the rover Curiosity.”

How Colors Smell – Julie Beck – The Atlantic

“But what color is the smell of, say, soap? A new study published in PLOS One finds that some people say white, some say yellow, some say blue. “

Suspects in science museum’s dinosaur heist turn themselves in – Andrew Kenney – Charlotte Observer

“A man and woman, both 21, turned themselves over to N.C. State Capitol Police on Thursday in the case of the missing model dinosaur.”

 

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Microbiome and general science digest, July 11

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Most recent results from American gut, a metagenomics pipeline, arsenic toxicity, polio and dengue vaccines, and pregnancy urine metabolomics to predict preterm birth.

Human gut microbiome

American GutAmerican Gut releases latest results and pipeline – Jeff Leach – American Gut

“The latest American Gut results are out and we’re very excited to share them with the American Gut community. We now have sequencing and analysis data from 3,238 participants, and as of today, this data equates to 101 million DNA sequences and 27 gigabytes of sequencing information.”

Screen shot 2014-07-11 at 04.27PM, Jul 11Place of upbringing in early childhood as related to inflammatory bowel diseases in adulthood: a population-based cohort study in Northern Europe – Signe Timm – European Journal of Epidemiology

“This study suggests a protective effect from livestock farm living in early childhood on the occurrence of IBD in adulthood, however only among subjects born after 1952. We speculate that lower microbial diversity is an explanation for the findings.”

Pregnancy and birth

Urinary pretermUrinary metabolic profiles in early pregnancy are associated with preterm birth and fetal growth restriction in the Rhea mother–child cohort study – Léa Maitre – BMC Medicine

“Here we used an exploratory metabolic profiling approach (metabolomics) to investigate the association between birth outcomes and metabolites in maternal urine collected early in pregnancy as part of the prospective mother–child cohort Rhea study. “

Metagenomics

MedusaMetagenomic Data Utilization and Analysis (MEDUSA) and Construction of a Global Gut Microbial Gene Catalogue – Fredrik H. Karlsson, Intawat Nookaew, Jens Nielsen – PLOS Computational Biology

“Here we present the bioinformatics pipeline MEDUSA that facilitates analysis of metagenomic reads at the gene and taxonomic level. We also constructed a global human gut microbial gene catalogue by combining data from 4 studies spanning 3 continents. “

Proteomics

Proteomics Staph aureusGenomics and Proteomics Provide New Insight into the Commensal and Pathogenic Lifestyles of Bovine and Human-associated Staphylococcus epidermidis strains – Kirsi Savijoki – Journal of Proteome Research

“Pilot experimental infection studies indicated that while ATCC12228 was able to infect bovine host, the PM221 strain caused more severe clinical signs. “

Dengue

Demanou DengueEvidence of Dengue Virus Transmission and Factors Associated with the Presence of Anti-Dengue Virus Antibodies in Humans in Three Major Towns in Cameroon – Maurice Demanou – PLOS Neglected Tropical Diseases

“Sera were screened for anti-dengue virus IgG and IgM antibodies. Risk factors of seropositivity were tested using logistic regression methods with random effects.”

Carrasco DenguePredictive Tools for Severe Dengue Conforming to World Health Organization 2009 Criteria – Luis R. Carrasco – PLOS Neglected Tropical Diseases

“Higher risk of severe dengue (SD) was associated with female gender, lower than normal hematocrit level, abdominal distension, vomiting and fever on admission. “

Infection and host response

Screen shot 2014-07-11 at 03.35PM, Jul 11Development of Fatal Intestinal Inflammation in MyD88 Deficient Mice Co-infected with Helminth and Bacterial Enteropathogens – Libo Su – PLOS Neglected Tropical Diseases

“We found that MyD88 knockout mice co-infected with H. polygyrus and C. rodentium developed more severe intestinal inflammation and elevated mortality compared to the wild-type mice.”‘

Screen shot 2014-07-11 at 04.28PM, Jul 11Distinct Lipid A Moieties Contribute to Pathogen-Induced Site-Specific Vascular Inflammation – Connie Slocum – PLOS Pathogens

“our results point to a pivotal role for activation of the non-canonical inflammasome in P. gingivalis infection and demonstrate that P. gingivalis evades immune detection at TLR4 facilitating chronic inflammation in the vasculature. “

Dengue

Dengue vaccine lancetClinical efficacy and safety of a novel tetravalent dengue vaccine in healthy children in Asia: a phase 3, randomised, observer-masked, placebo-controlled trial – Maria Rosario Capeding – The Lancet

“Our findings show that dengue vaccine is efficacious when given as three injections at months 0, 6, and 12 to children aged 2–14 years in endemic areas in Asia, and has a good safety profile. “

Also see comment: Dengue vaccines: dawning at last? – Annelies Wilder-Smith – The Lancet

Poliovirus

Jacob John polioEffect of a single inactivated poliovirus vaccine dose on intestinal immunity against poliovirus in children previously given oral vaccine: an open-label, randomised controlled trial – Jacob John – The Lancet

“The substantial boost in intestinal immunity conferred by a supplementary dose of IPV given to children younger than 5 years who had previously received OPV shows a potential role for this vaccine in immunisation activities to accelerate eradication and prevent outbreaks of poliomyelitis.”

Also see comment: Polio endgame management: focusing on performance with or without inactivated poliovirus vaccine – Kimberly M Thompson – The Lancet

Microbes in the News

Screen shot 2014-07-11 at 04.28PM, Jul 11 1How Gross Is Your Phone? A Motherboard Science Experiment – Jason Koebler – Motherboard

“All I wanted to do was recreate a relatively simple study I had just written about. Instead, I ended up creating something vaguely dangerous, which mortified the director of a local DIY biology lab. Here’s what happens when you perform experiments on your coworkers.”

Arsenic metabolism

Screen shot 2014-07-11 at 04.29PM, Jul 11Lung tumors in mice induced by “whole-life” inorganic arsenic exposure at human-relevant doses – Michael P. Waalkes – Archives of Toxicology

“Breeder male and female CD1 mice were exposed to 0, 50, 500 or 5,000 ppb arsenic (as sodium arsenite) in the drinking water for 3 weeks prior to breeding, during pregnancy and lactation, and after weaning (at week 3) groups of male and female offspring (initial n = 40) were exposed for up to 2 years.”

Dr. Bik’s Picks

Scorpions are master architects, according to new research – Science Daily

“The burrows made by scorpions follow a very sophisticated design, beginning with a short, vertical entrance shaft that flattened out a few centimeters below the surface into a horizontal platform, new research has found.”

Beach Sand Used To Make A Battery That Lasts Three Times Longer – Douglas Main – Popular Science

“Sink your toes into this: Beach sand can be used to make lithium-ion batteries that last three times longer than current models, according to a study published in the journal Scientific Reports.”

World Now “A Safer Place”, thanks to creation of Potential Pandemic Virus – The Allium

“Yes, I get your point that they could potentially kill millions of people and hospitalise millions more, causing untold human suffering and extraordinary economic damage, but think of all the advantages to the creation of these bugs”.

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Non-human microbiome digest, July 3

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Parasites, effect of antibiotics in pigs, microbiome of birds, Drosophila, microbiome of plant crops, Hawai’i waters, and bacteria to preserve stone monuments.

Parasites and microbiome

Cooperation and conflict in host manipulation: interactions among macro-parasites and micro-organisms – Frank Cézilly – Frontiers in Microbiology

“Here, we review the empirical evidence in favor of the existence of synergistic or antagonistic interactions between co-occurring parasites, and highlight the neglected role of micro-organisms. “

holobiontHolobiont–Holobiont Interactions: Redefining Host–Parasite Interactions – Nolwenn Marie Dheilly – PLOS Pathogens

“It has been established in different model species that immune system maturation requires the presence of mutualistic bacteria”

Marine mammal microbiome

Screen shot 2014-07-03 at 04.24PM, Jul 03Intestinal helminth fauna of striped dolphins (Stenella coeruleoalba) in the western Mediterranean: No effects of host body length, age and sex – Paula Mateu – Marine Mammal Science

“The intestine of 52 (28 males and 24 females) striped dolphins (Stenella coeruleoalba) from western Mediterranean waters was examined for helminths. Animals were found stranded along the Spanish coasts during the morbillivirus epizootic in 1990.”

Pig microbiome

Screen shot 2014-07-03 at 03.17PM, Jul 03Carbadox has both temporary and lasting effects on the swine gut microbiota – Torey Looft – Frontiers in Microbiology

“Carbadox is an in-feed antibiotic that is widely used in swine production to prevent dysentery and to improve feed efficiency. The goal of this study was to characterize the effects of carbadox and its withdrawal on the swine gut microbiota. ”

Screen shot 2014-07-03 at 03.18PM, Jul 03Learning from agriculture: understanding low-dose antimicrobials as drivers of resistome expansion – Yaqi You – Frontiers in Microbiology

“Unconfined storage or land deposition of a large volume of animal waste causes its wide contact with the environment and drives the expansion of the environmental resistome through mobilome facilitated horizontal genet (sic, EB) transfer. “

Bird microbiome

Screen shot 2014-07-03 at 03.18PM, Jul 03Interspecific variations in the faecal microbiota of Procellariiform seabirds – Meagan L. Dewar – FEMS Microbiology Ecology

“Examining the faecal microbiota of three Procellariiform species (short-tailed shearwater, common diving petrel and fairy prion) provided a unique opportunity to not only characterise the gastrointestinal (GI) microbial composition of seabirds but to also examine the influence of stomach oils on the microbial community.”

Insect microbiome

Drosophila modelTransient adult microbiota, gut homeostasis and longevity: Novel insights from the Drosophila model – Berra Erkosar, Francois Leulier – FEBS Letters

“In the last decade, Drosophila has emerged as a useful model to study host–microbiota interactions, creating an active research field with prolific publications.”

Plant microbiome

Screen shot 2014-07-03 at 03.21PM, Jul 03Building the crops of tomorrow: advantages of symbiont-based approaches to improving abiotic stress tolerance – Devin Coleman-Derr – Frontiers in Microbiology

“In recent years, studies have attempted to identify microbial symbionts capable of conferring the same stress-tolerance to their plant hosts, and new developments in genomic technologies have greatly facilitated such research. “

Screen shot 2014-07-03 at 03.21PM, Jul 03Convergence in mycorrhizal fungal communities due to drought, plant competition, parasitism, and susceptibility to herbivory: consequences for fungi and host plants – Catherine A. Gehring – Frontiers in Microbiology

“We found that drought and all three of the biotic interactions studied resulted in similar shifts in ectomycorrhizal fungal community composition, demonstrating a convergence of the community towards dominance by a few closely related fungal taxa.”

Screen shot 2014-07-03 at 03.22PM, Jul 03Nitrogen-fixing Rhizobium-legume symbiosis: are polyploidy and host peptide-governed symbiont differentiation general principles of endosymbiosis? – Gergely Maróti- Frontiers in Microbiology

“This review focuses on symbiotic plant cell development and terminal bacteroid differentiation and demonstrates the crucial roles of symbiotic peptides”

Screen shot 2014-07-03 at 03.22PM, Jul 03Disparate origins of Bradyrhizobium symbionts for invasive populations of Cytisus scoparius (Leguminosae) in North America – Kevin Horn – FEMS Microbiology Ecology

“To identify the geographic origin of nodule bacteria associated with invasion of the European legume Cytisus scoparius in the United States, isolates from 15 sites in six states were compared to > 200 Bradyrhizobium strains from indigenous legumes in the U.S., Mexico, Europe (six countries), Morocco, and Australia. “

Food microbiology

Screen shot 2014-07-03 at 03.24PM, Jul 03Weissella confusa: problems with identification of an opportunistic pathogen that has been found in fermented foods and proposed as a probiotic – Marilynn R. Fairfax – Frontiers in Microbiology

“Weissella confusa is found in fermented foods and has been suggested as a probiotic, but also causes sepsis and other serious infections in humans and animals.”

Stone microbiology

Screen shot 2014-07-03 at 03.24PM, Jul 03 1Application of calcifying bacteria for remediation of stones and cultural heritages – Navdeep Kaur Dhami – Frontiers in Microbiology

“The present review emphasizes about different causative agents leading to deterioration and application of microbially induced calcium carbonate precipitation as a novel and potential technology for dealing with these problems. “

Soil microbiology

Screen shot 2014-07-03 at 03.25PM, Jul 03Volatile-mediated interactions between phylogenetically different soil bacteria
Paolina Garbeva – Frontiers in Microbiology

“Here we report that volatile compounds emitted by different soil bacteria can affect the growth, antibiotic production and gene expression of the soil bacterium Pseudomonas fluorescens Pf0–1. “

Screen shot 2014-07-03 at 03.27PM, Jul 03Land-use influences the distribution and activity of high affinity CO-oxidizing bacteria associated to type I-coxL genotype in soil – Liliana Quiza – Frontiers in Microbiology

“The main objective of this study was to assess the impact of land-use and soil properties on coxL gene diversity and identify molecular indicators for the soil uptake of atmospheric CO.”

Screen shot 2014-07-03 at 03.26PM, Jul 03Abundance and community structure of ammonia-oxidizing Archaea and Bacteria in response to fertilization and mowing in a temperate steppe in Inner Mongolia –
Yong-Liang Chen – FEMS Microbiology Ecology

“… we investigated the effects of nitrogen (N) and phosphorus (P) fertilization and mowing on the abundance and community compositions of ammonia-oxidizing Bacteria (AOB) and Archaea (AOA) upon early (May) and peak (August) plant growth using quantitative PCR (qPCR), terminal-restriction fragment length polymorphism (T-RFLP), cloning and sequencing. “

Water microbiology

Screen shot 2014-07-03 at 03.27PM, Jul 03Biogeography of planktonic and benthic cyanobacteria in coastal waters of the Big Island, Hawai’i – Samuel D. Chamberlain – FEMS Microbiology Ecology

“To understand the patterns of cyanobacterial biogeography in relation to coastal environmental factors, we examined the diversity of planktonic and benthic cyanobacteria at 12 sites along the west coast of Hawaii’s Big Island.”

Screen shot 2014-07-03 at 03.29PM, Jul 03Rhizosphere heterogeneity shapes abundance and activity of sulfur-oxidizing bacteria in vegetated salt marsh sediments – François Thomas – Frontiers in Microbiology

“We combined next-generation amplicon sequencing of 16S rDNA and rRNA libraries with phylogenetic analyses of marker genes for two S-oxidation pathways (soxB and rdsrAB). Gene and transcript numbers of soxB and rdsrAB phylotypes were quantified simultaneously, using newly designed (RT)-qPCR assays.”

Screen shot 2014-07-03 at 03.28PM, Jul 03Neotropical Andes hot springs harbor diverse and distinct planktonic microbial communities – Luisa Delgado-Serrano – FEMS Microbiology Ecology

“In this study, we describe and compare the planktonic microbial communities present in five high-mountain hot springs with distinct geochemical characteristics, at varying altitudes and geographical locations in the Colombian Andes. “

Screen shot 2014-07-03 at 03.29PM, Jul 03Occurrence and activity of anammox bacteria in surface sediments of the southern North Sea – Nicole J. Bale – FEMS Microbiology Ecology

“The presence of anammox bacteria was established through the detection of specific phosphocholine-monoether ladderane lipids, 16S rRNA gene, and hydrazine synthase (hzsA) genes. “

Screen shot 2014-07-03 at 03.29PM, Jul 03 1Bacterial community structure and dissolved organic matter in repeatedly flooded subsurface karst water pools – Tanja Shabarova – FEMS Microbiology Ecology

“Bacterial diversity, community assembly, and the composition of the dissolved organic matter (DOM) were studied in three temporary subsurface karst pools with different flooding regimes.”

Screen shot 2014-07-03 at 03.30PM, Jul 03Abundance, diversity and seasonal dynamics of predatory bacteria in aquaculture zero discharge systems – Prem P. Kandel – FEMS Microbiology Ecology

“The dynamics of populations belonging to the obligate predators Bdellovibrio and like organisms (BALOs) were analyzed in freshwater and saline ZDS over a 7-month period using QPCR targeting the Bdellovibrionaceae, and the Bacteriovorax and Bacteriolyticum genera in the Bacteriovoracaeae”

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Human microbiome digest, July 3

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Short chain fatty acids and gut microbiota, microbial eukaryotes in the human gut, Pseudomonas in stool, and a smelly Anaerococcus isolated from arm pits.

Gut microbiome

Fernandes ObeseAdiposity, gut microbiota and faecal short chain fatty acids are linked in adult humans – J Fernandes – Nutrition & Diabetes

“Our objectives were to compare dietary intakes, faecal SCFA concentrations and gut microbial profiles in healthy lean (LN, BMIless than or equal to25) and overweight or obese (OWOB, BMI>25) participants.”

Ellagic Acid Metabolism by Human Gut Microbiota: Consistent Observation of Three Urolithin Phenotypes in Intervention Trials, Independent of Food Source, Age, and Health Status – Francisco A. Tomás-Barberán – Journal of Agricultural and Food Chemistry

“Interestingly, a higher percentage of phenotype B was observed in those volunteers with chronic illness (metabolic syndrome or colorectal cancer) associated with gut microbial imbalance (dysbiosis).”

Screen shot 2014-07-03 at 03.04PM, Jul 03Communities of microbial eukaryotes in the mammalian gut within the context of environmental eukaryotic diversity – Laura Wegener Parfrey – Frontiers in Microbiology

“We curated the SILVA ribosomal database to reflect current knowledge of eukaryotic taxonomy and employ it as a phylogenetic framework to compare eukaryotic diversity across environment. We show that adults from the non-western population harbor a diverse community of protists, and diversity in the human gut is comparable to that in other mammals.”

Screen shot 2014-07-03 at 03.04PM, Jul 03Faecal carriage of Pseudomonas aeruginosa in healthy humans: antimicrobial susceptibility and global genetic lineages – Vanesa Estepa – FEMS Microbiology Ecology

“The aim of this study was to analyse the Pseudomonas aeruginosa faecal carriage rate in 98 healthy humans and to perform the phenotypic and genotypic characterization of recovered isolates. The genetic relatedness among the isolates was analysed by pulsed-field gel electrophoresis and multilocus sequence typing that was compared with worldwide epidemic clones. “

helminth infectHelminth Infections, Type-2 Immune Response, and Metabolic Syndrome – Aprilianto E. Wiria – PLOS Pathogens

“Are Helminth Infections Associated with Metabolic Syndrome?”

Skin microbiome

Screen shot 2014-07-03 at 03.02PM, Jul 03A newly discovered Anaerococcus strain responsible for axillary odor and a new axillary odor inhibitor, pentagalloyl glucose – Takayoshi Fujii – FEMS Microbiology Ecology

“We aimed to investigate anaerobic bacteria that had not been previously studied for axillary odor formation. A new anaerobic Anaerococcus sp. A20, that releases 3-hydroxy-3-metyl-hexanoic acid (HMHA, main component of axillary odor) from its glutamyl conjugate, was discovered from axillary isolates. “

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General microbiology and science, June 27

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Viruses in primate genomes, viruses altering shrimp metabolome, transposable elements and repeats, dengue, other infectious diseases in developing countries and Dr. Bik’s Picks.

Metagenomics / viruses

Screen Shot 2014-06-27 at 9.21.29 PMCute animal alert! A tarsier is a tiny primate with huge eyes.
The First Endogenous Herpesvirus, Identified in the Tarsier Genome, and Novel Sequences from Primate Rhadinoviruses and Lymphocryptoviruses – Amr Aswad, Aris Katzourakis – PLOS Genetics

“We describe the first endogenous herpesvirus from the genome of the Philippine tarsier, belonging to the Roseolovirus genus, and characterize its highly defective genome that is integrated and flanked by unambiguous host DNA. From a draft assembly of the aye-aye genome, we use bioinformatic tools to reveal over 100,000 bp of a novel rhadinovirus that is the first lemur gammaherpesvirus, closely related to Kaposi’s sarcoma-associated virus.”

 Metabolomics

Screen Shot 2014-06-27 at 9.32.37 PMAn Invertebrate Warburg Effect: A Shrimp Virus Achieves Successful Replication by Altering the Host Metabolome via the PI3K-Akt-mTOR Pathway – Mei-An Su – PLOS Pathogens

“We show that the PI3K-Akt-mTOR pathway was of central importance in triggering this WSSV-induced Warburg effect. Although dsRNA silencing of the mTORC1 activator Rheb had only a relatively minor impact on WSSV replication, in vivo chemical inhibition of Akt, mTORC1 and mTORC2 suppressed the WSSV-induced Warburg effect and reduced both WSSV gene expression and viral genome replication.”

Biofilms

Screen Shot 2014-06-27 at 9.33.21 PMFilaments in curved streamlines: rapid formation of Staphylococcus aureus biofilm streamers – Minyoung Kevin Kim – New Journal of Physics

“We discovered that S. aureus rapidly forms flow-induced, filamentous biofilm streamers, and furthermore if surfaces are coated with human blood plasma, streamers appear within minutes and clog the channels more rapidly than if the channels are uncoated. “

Chromosomal organization

Screen Shot 2014-06-27 at 9.34.04 PMDigital Genotyping of Macrosatellites and Multicopy Genes Reveals Novel Biological Functions Associated with Copy Number Variation of Large Tandem Repeats – Manisha Brahmachary – PLOS Genetics

“Here, we demonstrate the utility of Nanostring technology as a targeted approach to perform accurate measurement of tandem repeats even at extremely high copy number, and apply this technology to genotype 165 HapMap samples from three different populations and five species of non-human primates. “

Screen Shot 2014-06-27 at 9.34.37 PMLarge-Scale Genomic Analysis Suggests a Neutral Punctuated Dynamics of Transposable Elements in Bacterial Genomes – Jaime Iranzo – PLOS Computational Biology

“In this work, we take advantage of the large amount of genomic data currently available and study the abundance distributions of 33 IS families in 1811 bacterial chromosomes. This allows us to test simple models of IS dynamics and estimate their key parameters by means of a maximum likelihood approach. “

Microbial Ecology

Screen Shot 2014-06-27 at 9.35.00 PMEx Uno Plures: Clonal Reinforcement Drives Evolution of a Simple Microbial Community – Margie Kinnersley – PLOS Genetics

“We previously showed that a population of E. coli that originated from a single clone and was cultured in the presence of a single limiting resource, evolves into a stable, three-membered community, wherein one clone excretes metabolites that the others utilize as carbon sources. To discern the genetic factors at work in producing this outcome and to illuminate the community’s physiology, we sequenced the genomes of the ancestral and evolved clones.”

Infectious diseases in developing countries

Screen Shot 2014-06-27 at 9.35.43 PMExploring the Relationship between Access to Water, Sanitation and Hygiene and Soil-Transmitted Helminth Infection: A Demonstration of Two Recursive Partitioning Tools – Katherine Gass – PLOS Neglected Tropical Diseases

“Improvements to water, sanitation and hygiene (WASH) likely provide sustained benefit, but few rigorous studies have evaluated the specific WASH components most influential in reducing infection. “

Screen Shot 2014-06-27 at 9.36.14 PMSocial Sciences Research on Infectious Diseases of Poverty: Too Little and Too Late? – José Azoh Barry – PLOS Neglected Tropical Diseases

“Besides the vicious circle these diseases maintain with dire conditions of poverty, an increased microbial resistance to some therapeutic drugs adds to the complexity of health disparities and human suffering among the socially disadvantaged, marginalized, and prejudiced against.”

Dengue

Screen Shot 2014-06-27 at 9.36.37 PMVariability in Dengue Titer Estimates from Plaque Reduction Neutralization Tests Poses a Challenge to Epidemiological Studies and Vaccine Development – Henrik Salje – PLOS Neglected Tropical Diseases

“We used repeated assays on the same two pools of serum using five different viruses (2,319 assays) to characterize the variability in the technique under identical experimental conditions. We also assessed the performance of multiple statistical models to interpolate continuous values of neutralization titer from discrete measurements from serial dilutions.”

Science and career

PLOSTen Simple Rules for Approaching a New Job – Philip E. Bourne – PLOS Computational Biology

“Thinking both as a job applicant and a job interviewer about how I have approached job situations over the years before, during, and after the interview and how those situations have turned out, I can offer the following ten simple rules as you prepare.”

A New Online Computational Biology Curriculum – David B. Searls – PLOS Computational Biology

“A recent proliferation of Massive Open Online Courses (MOOCs) and other web-based educational resources has greatly increased the potential for effective self-study in many fields. This article introduces a catalog of several hundred free video courses of potential interest to those wishing to expand their knowledge of bioinformatics and computational biology. “

Arsenic metabolism

Screen Shot 2014-06-27 at 10.00.06 PMAssociations between Arsenic Species in Exfoliated Urothelial Cells and Prevalence of Diabetes among Residents of Chihuahua, Mexico – Jenna M. Currier – Environ Health Perspect

“We measured concentrations of trivalent and pentavalent iAs, methyl-As (MAs), and dimethyl-As (DMAs) species in EUC from 374 residents of Chihuahua, Mexico, who were exposed to iAs in drinking water.”

Dr. Bik’s Picks

Screen Shot 2014-06-27 at 10.09.01 PMWith pictures and videos: Duration of urination does not change with body size – Patricia J. Yang – PNAS

“In this study, we report a mathematical model that clarifies misconceptions in urology and unifies the results from 41 independent urological and anatomical studies. The theoretical framework presented may be extended to study fluid ejection from animals, a universal phenomenon that has received little attention.”

Screen Shot 2014-06-27 at 10.01.44 PMFrom Gemstones to Arsenic: How the Development of Pigment Colored Art – Allison Meier

“A new exhibition at London’s National Gallery — Making Colour — looks at the development of color in art, from the Middle Ages to 1900. “

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Human microbiomes, June 5

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Today we have some commentaries on recent papers about microbiotas in malnutrition or on placentas, and new papers about oral bacteria in the bloodstream, helminths, and coincidental killers.

Oral microbiome

Screen Shot 2014-06-05 at 7.59.36 PMDissemination of Periodontal Pathogens in the Bloodstream after Periodontal Procedures: A Systematic Review – Anna Carolina Ratto Tempestini Horliana – PLOS ONE

“MEDLINE, EMBASE and LILACS databases were searched in duplicate through August, 2013 without language restriction. Observational studies were included if blood samples were collected before, during or after periodontal procedures of patients with periodontitis”

Screen Shot 2014-06-05 at 7.56.12 PMThe Emerging Landscape of Salivary Diagnostics – Yong Zhang- OHDM – Omics Online

“Here we review recent developments in salivary diagnostics that have been accomplished using salivaomics, the mechanisms of saliva diagnostics, as well as the translational and clinical application of saliva biomarkers”

Gut microbiome

Screen Shot 2014-06-05 at 7.57.14 PMInfection and Co-infection with Helminths and Plasmodium among School Children in Côte d’Ivoire: Results from a National Cross-Sectional Survey – Richard B. Yapi – PLOS Neglected Tropical Diseases

“We carried out the first national survey on parasitic worm and Plasmodium infection among children in 92 schools all over Côte d’Ivoire. Questionnaires were administered to determine the children’s socioeconomic status and infection-related risk factors. We found an overall prevalence of Plasmodium infection of 63.3%.”

ColonSome Antibiotics May Slightly Increase Colon Cancer Risk – Bahar Gholipour – LiveScience

“The researchers compared the amount of antibiotics the patients had taken at least six months before being diagnosed with cancer, to the amount of antibiotics taken by a group of about 86,000 healthy people.”

Screen Shot 2014-06-05 at 10.07.58 AMWhy Can’t Once-Malnourished Children “Catch Up”? Answer May Lie in Gut – Karen Weintraub – National Geographic

“There’s something lacking in our current approach to treatment,” said Gordon, who suspects the children may need to eat therapeutic foods for longer and/or get supplements of probiotics, or beneficial microorganisms, to catch up. “We need to think of food as interacting with this microbial organ.”

Screen Shot 2014-06-05 at 8.03.26 PMSevere hunger can have lasting effects for gut health, study finds – MedicalXPress

“Nutrition therapy has saved the lives of millions of malnourished infants, but may not restore an imbalance in gut bacteria that is key to long-term health and vitality, researchers said Wednesday.”

Pregnancy and birth

Screen Shot 2014-06-05 at 8.05.15 PMGearing up for a closer look at the human placenta – Jocelyn Kaiser – Science

“A placenta sustained you and every person ever born for 9 months, serving as your lungs and kidneys and pumping out hormones while you developed in the womb. Problems with this disk-shaped mass of tissue can contribute to everything from preterm births to diseases of middle age. Yet when a baby is born, hospitals usually throw the placenta away.”

Screen Shot 2014-06-05 at 9.57.32 AMMicrobirth: Why ‘Seeding Baby’s Microbiome’ Needs to Be on Every Birth Plan – Toni Harman – HuffingtonPost

“The latest scientific research is now starting to indicate that if the baby is not properly seeded with the mother’s own bacteria at birth, then the baby’s microbiome, in the words of Rodney R Dietert, Professor of Immunotoxicology at Cornell University, is left “incomplete”.”

General human microbiome

Screen Shot 2014-06-05 at 8.07.51 PMCoincidental killers – We assume that microbes evolved to attack humans when actually we are just civilian casualties in a much older war – Ed Yong – Aeon Magazine

“And some supposedly pathogenic bacteria were often common parts of the environment. ‘These organisms become accidental pathogens,’ says the microbiologist Arturo Casadevall from Yeshiva University in New York. ‘They’ll still be there even if you remove all the animals from the planet. And yet, evolution selected for just the right combination of traits to cause disease in humans.’”

Screen Shot 2014-06-05 at 8.12.08 PMSilicon Valley’s Top Ten Tech Trends – Jacqueline Vanacek – Forbes
Trend #7: Data-driven healthcare (from your gut).

The combination of personal health and fitness data, genomics, and even microbiomics will drive healthcare choices from real outcomes and individual probabilities. And since the bacteria in our digestive tracks has greater influence on our health than previously known, we really are what we eat!

Microbiome and Bioinformatics

Screen Shot 2014-06-05 at 8.11.20 PMBOTUX: Bayesian–like operational taxonomic unit examiner – Vishal N. Koparde – International Journal of Computational Biology and Drug Design

“Bayesian–like operational taxonomic unit examiner (BOTUX) is a new tool for the classification of 16S rRNA gene sequences into operational taxonomic units (OTUs) that addresses the problem of overestimation caused by errors introduced during PCR amplification and DNA sequencing steps”

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