Category Archives: Metagenomics & Bioinformatics

General microbiology and science digest, September 16, 2014

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Detection of microbes in tissues, a magnet to pull out bacteria from blood, temperature stability of samples, enriching for rare microbial community members, bioinformatics tools for microbiome research, and Bik’s Picks.
Microbial detection

Metagenomic Assay for Identification of Microbial Pathogens in Tumor Tissues – Don A. Baldwin – mBio

“the PathoChip platform was developed by targeting viral, prokaryotic, and eukaryotic genomes with multiple DNA probes in a microarray format that can be combined with a variety of upstream sample preparation protocols and downstream data analysis. “

More microbes

Review: Physical stress and bacterial colonization – Michael Otto – FEMS Microbiology Reviews

“This review will give an overview over the mechanisms human bacterial colonizers have to withstand physical stresses with a focus on bacterial adhesion.”

Techniques

16S rRNA gene pyrosequencing of reference and clinical samples and investigation of the temperature stability of microbiome profiles – Jun Hang – Microbiome

“Three readily available mock bacterial community materials and two commercial extraction techniques, Qiagen DNeasy and MO BIO PowerSoil DNA purification methods, were used to assess procedures for 16S ribosomal DNA amplification and pyrosequencing-based analysis.”

Improving the genetic representation of rare taxa within complex microbial communities using DNA normalisation methods – Dragana Gagic – Molecular Ecology Resources

“The synthetic metagenome was fractionated and thermally re-natured, allowing the most abundant sequences to hybridise. Double-stranded DNA was removed either by hydroxyapatite chromatography, or by a duplex-specific nuclease (DSN).”

Bioinformatics

A better sequence-read simulator program for metagenomics – Stephen Johnson – BMC Bioinformatics

“We present BEAR (Better Emulation for Artificial Reads), a program that uses a machine-learning approach to generate reads with lengths and quality values that closely match empirically-derived distributions.”

Gene finding in metatranscriptomic sequences – Wazim Mohammed Ismail, Yuzhen Ye and Haixu Tang – BMC Bioinformatics

“In this paper, we present TransGeneScan, a software tool for finding genes in assembled transcripts from metatranscriptomic sequences.”

Data analysis for 16S microbial profiling from different benchtop sequencing platforms
Victor S. Pylro – Journal of Microbiological Methods

“Satisfactory results were obtained in those pipelines that applied a chimera-filtering step.”

Metagenome fragment classification based on multiple motif-occurrence profiles – Naoki Matsushita – PeerJ

“we have updated the Naïve Bayes Classifier method using multiple sets of occurrence profiles for each reference genome by normalizing the genome sizes, dividing each genome sequence into a set of subsequences of similar length and generating profiles for each subsequence.”

Revolutionizing prokaryotic systematics through next-generation sequencing – Vartul Sangal – Methods in Microbiology

“In this chapter, we have provided a brief summary of recent advances in sequencing technologies and easy to use bioinformatic tools to analyse sequence data, with a focus on prokaryotic biology. “

Microbes in the news

A Lesson in Language – McAlarnen, Lindsey A. – Academic Medicine

“while I expected a challenge working with human microbiome expert Dr. Rob Knight, I never expected to be as lost as I was that first morning.”

An extracorporeal blood-cleansing device for sepsis therapy – Joo H Kang – Nature Medicine

“Magnets pull the opsonin-bound pathogens and toxins from the blood; the cleansed blood is then returned back to the individual. “

Science and career

Too Few University Jobs For America’s Young Scientists – Richard Harris – NPR Morning Edition

“Imagine a job where about half of all the work is being done by people who are in training. That’s, in fact, what happens in the world of biological and medical research.”

Diversity in Science: Where Are the Data? – Fred Guterl – Scientific American

“Global figures on diversity in the science and engineering workforce are hard to come by, but what we know is not flattering”

 

Bik’s Picks

Jack the Ripper, more poison at NIH, Rosetta & the comet – Tabitha M. Powledge – PLOS Blogs

“Scientists have greeted with hoots and catcalls the claim that Jack the Ripper, the near-mythical late-19th Century London serial killer, has been identified from DNA as an immigrant Polish baker named Aaron Kosminski.”

Human faces are so variable because we evolved to look unique – ScienceDaily

“The amazing variety of human faces — far greater than that of most other animals — is the result of evolutionary pressure to make each of us unique and easily recognizable”

Joanne Chang Brings the Sweet Science of Sugar to Harvard – Leah Blumenthal – Eater.com

“Harvard University’s annual Science & Cooking public lecture series brings chefs from around the world to lecture on the intersection of science and cooking.”

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General microbiology and science, September 15, 2014

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Biodiversity and evolution in microbial communities, metabolomics, swabbing, DNA extraction, ITS approaches, marine viruses, and Bik’s Picks.

Microbial Ecology

The cryptic role of biodiversity in the emergence of host–microbial mutualisms – Pradeep Pillai – Ecology Letters

“Using a metacommunity model, we show that competition between multiple cheaters within the host’s microbiome, when combined with the spatial structure of host–microbial interactions, can have a constructive rather than a disruptive effect by allowing the emergence and maintenance of mutualistic microorganisms within the host.”

Microbial communities evolve faster in extreme environments – Sheng-Jin Li – Nature Scientific Reports

“Here we report a relative evolutionary rates (rERs) analysis of microbial communities from six diverse natural environments based on 40 metagenomic samples. “

Metabolomics

Mapping the Inner Workings of the Microbiome: Genomic- and Metagenomic-Based Study of Metabolism and Metabolic Interactions in the Human Microbiome – Ohad Manor, Roie Levy, Elhanan Borenstein – Cell Metabolism

“Here, we discuss recent efforts to study the metabolic inner workings of this complex ecosystem. “

Techniques

Comparison of seven methods for extraction of bacterial DNA from fecal and cecal samples of mice – Janina Ferrand – Journal of Microbiological Methods

“DNA quantity and quality were assessed by fluorometry, spectrophotometry, gel electrophoresis and qPCR….For both feces and intestinal contents, the most efficient extraction method was the FastDNA® SPIN Kit for Soil.”

Swab Sample Transfer for Point-Of-Care Diagnostics: Characterization of Swab Types and Manual Agitation Methods – Nuttada Panpradist – PLOS ONE

“In this study, we compared bacterial release efficiency of seven swab types using manual-agitation methods typical of POC devices.”

Improved resolution of bacteria by high throughput sequence analysis of the rRNA internal transcribed spacer – Paul M. Ruegger – Journal of Microbiological Methods

“Comparisons of the ITS region and two SSU regions using annotated bacterial genomes in GenBank showed much greater resolving power is possible with the ITS region. “

Pyroprinting: A rapid and flexible genotypic fingerprinting method for typing bacterial strains – Michael W. Black – Journal of Microbiological Methods

“Pyroprinting relies on the simultaneous pyrosequencing of polymorphic multicopy loci, such as the intergenic transcribed spacer regions of rRNA operons in bacterial genomes.”

Bioinformatics

OrthoClust: an orthology-based network framework for clustering data across multiple species – Koon-Kiu Yan – Genome Biology

“We demonstrate the application of OrthoClust using the RNA-Seq expression profiles of Caenorhabditis elegans and Drosophila melanogaster from the modENCODE consortium.”

Viruses and Phages

Review: Factors affecting virus dynamics and microbial host–virus interactions in marine environments – Kristina D.A. Mojica and Corina P.D. Brussaard – FEMS Microbiology Ecology

“The goal of the present minireview was to contribute to the evolution of marine viral ecology, through the assimilation of available data regarding the manner and degree to which environmental factors affect viral decay and infectivity as well as influence latent period and production.”

More Microbes

Dead or Alive: Molecular Assessment of Microbial Viability – Gerard A. Cangelosi and John S. Meschke – Applied and Environmental Microbiology

“This article reviews molecular viability analysis in that context and discusses future opportunities for these strategies in genetic, metagenomic, and single-cell microbiology.”

Bacteria in the news

Is your body mostly microbes? Actually, we have no idea – Peter Andrey Smith – The Boston Globe

“There’s only one problem: The oft-cited 10-to-1 figure is almost certainly inaccurate.”

The Death Microbiome Could Inform Forensic Science And Medicine – Randall Mayes – Design & Trend

“For pathologists working out the time of death, research has focused on the way that insects and microbes from a corpse’ environment take up residence in the flesh.”

Tiny hitchhikers, big health impact: Studying the microbiome to learn about disease – Krista Conger – ScopeBlog Stanford

Got microbes? Meet some of the tiny life forms that call you home and may make antibiotics for you (with annoying 5 questions if you want to read the whole article) – Susannah Bodman – Oregon Live

Fighting Poisons With Bacteria – Going Inside the Rice Microbiome – Carina Storrs – NY Times

“Dr. Bais is working to develop rice plants that take up less arsenic, a common contaminant in the fields of his native India and other Asian countries.”

Possum faeces may cause flesh-eating ulcers in humans, Victorian researchers say – ABC Australia

“Infectious disease researchers at Victoria’s Barwon Health have found that possums can carry the buruli bacteria, which can cause major skin ulcers in humans.”

Scientific publishing

Ten Simple Rules for Better Figures – Nicolas P. Rougier – PLOS Computational Biology

“we aim to provide a basic set of rules to improve figure design and to explain some of the common pitfalls.”

The digital toolbox – Nature Editorial

“A new section of Nature examines the software and websites that make research easier.”

Scientific career

There is life after academia – Nature Editorial

“With high numbers of postdocs emerging from universities, prospective PhD students must be prepared for the fact that they will probably not end up with a career in research.”

Bik’s Picks

PBS: Video on the science behind brewing beer hops to it – CNET

“PBS series “It’s Okay To Be Smart” takes a look at how beer is made, and what external factors influence the final product.”

The coffee genome provides insight into the convergent evolution of caffeine biosynthesis -France Denoeud – Science

“We generated a high-quality draft genome of the species Coffea canephora, which displays a conserved chromosomal gene order among asterid angiosperms. “

On the Other Hand – Bob Grant – The Scientist

“Handedness, a conspicuous but enigmatic human trait, may be shared by other animals. What does it mean for evolution and brain function?”

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Microbiome Digest, August 29, 2014

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@MicrobiomDigest will be enjoying vacation for the next two weeks, so I won’t be able to post as much as usual. I might occasionally have some time and internet access at the same time, and post something, but don’t rely on this blog during that time for your daily Microbiome fix. But I will be back! Enjoy this last (short) one for now:
Human oral microbiome

Bacterial community composition of chronic periodontitis and novel oral sampling sites for detecting disease indicators – Vaia Galimanas – Microbiome

Human gut microbiome

Immunoglobulin A Coating Identifies Colitogenic Bacteria in Inflammatory Bowel Disease – Noah W Palm – Cell

Modulation of immune development and function by intestinal microbiota – Agnieszka M. Kabat – Trends in Immunology

 

Worms, bacteria, and micronutrients: an elegant model of our diet – Lutfu Safak Yilmaz, Albertha J.M. Walhout – Trends in Genetics

 

Mammal microbiome

Spatial heterogeneity of gut microbiota reveals multiple bacterial communities with distinct characteristics (in flying squirrels) – Hsiao-Pei Lu – Scientific Reports

Social influences on the gut microbiome of developing monkeys – W.Z. Amaral – Brain, Behavior, and Immunity

 

Do Rumen Bacteroidetes Utilize an Alternative Mechanism for Cellulose Degradation? – AE Naas – mBio

 

Characterization of the Fecal Microbiota of Pigs before and after Inoculation with “Brachyspira hampsonii” – Matheus O. Costa – PLOS ONE

 

Sponges and corals

The versatile nature of coral-associated viruses – Bettarel Yvan – Environmental Microbiology

Onset and establishment of diazotrophs and other bacterial associates in the early life history stages of the coral Acropora millepora – Kimberley A. Lema – Molecular Ecology

Rocks and Water Microbiome

Microbial Colonization of Bare Rocks: Laboratory Biofilm Enhances Mineral Weathering – F. Seiffert – Procedia Earth and Planetary Science

Microbial diversity and biogeochemical cycling in soda lakes – Dimitry Y. Sorokin – Extremophiles

Food microbiome

Switzerland Puts Secret Bacteria In Cheese To Catch Knockoffs – Sarah Zhang – Gizmodo

Bioinformatics

A Scalable and Accurate Targeted Gene Assembly Tool (SAT-Assembler) for Next-Generation Sequencing Data – Yuan Zhang – PLOS Computational Biology

Metabolomics

Taking your breath away: metabolomics breathes life in to personalized medicine
Nicholas J.W. Rattray – Trends in Biotechnology

Phages and Viruses

Identifying and analyzing bacteriophages in human fecal samples: what could we discover? – Maite Muniesa1 & Juan Jofre – Future Medicine

Microbes in the news

Hotel rooms aren’t yucky – you colonize them with your own personal bacteria within hours — Rachel Feltman – Washington Post

A touching story: The ancient conversation between plants, fungi and bacteria – David Tenenbaum – News UW Madison

Bik’s Picks

The universal ‘anger face’: Each element makes you look physically stronger and more formidable – Science Daily

Zombie Bacteria Invasion? Nothing To Worry About – Science 2.0

Report: Ice Bucket Challenge Causing Ecological Mayhem in California – The Allium (Satire)

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General microbiology and science, August 25, 2014

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Microbial networks, proteomics of Fusobacterium, ants carrying pathogens into hospitals, and what’s in your lab freezer?

Bioinformatics

Sparse and compositionally robust inference of microbial ecological networks – Zachary D. Kurtz – arXiv at Cornel University Library

“Here, we present SPIEC-EASI (SParse InversE Covariance Estimation for Ecological Association Inference), a statistical method for the inference of microbial ecological interactions from metagenomic datasets that addresses both of these issues. “

Metabolomics / proteomics

Modelling the Emergent Dynamics and Major Metabolites of the Human Colonic Microbiota – Helen Kettle – Environmental Microbiology

“We present here a first attempt at modelling microbial dynamics in the human colon incorporating both uncertainty and adaptation. “

Proteomics of Fusobacterium nucleatum within a model developing oral microbial community  – Erik L. Hendrickson – MicrobiologyOpen

“About 1210 F. nucleatum proteins were detected in single species F. nucleatum control samples, 1192 in communities with P. gingivalis, 1224 with S. gordonii, and 1135 with all three species.”

Techniques

* (Preprint) Sources of PCR-induced distortions in high-throughput sequencing datasets – Justus M Kebschull, Anthony M Zador – bioRXiv

“We examined the effects of bias, stochasticity, template switches and polymerase errors introduced during PCR on sequence representation in next-generation sequencing libraries. “

More microbes

* Ants as vectors of pathogenic microorganisms in a hospital in Sao Paulo county, Brazil – Heros J Máximo – BMC Research Notes

“Ants in hospitals may carry both Gram-positive and Gram-negative bacteria, and methods of controlling urban ants should be adopted and strictly adhered to, to minimize the risk of infection in hospital patients.”

Microbes in the news

What’s in your laboratory freezer? – Timothy J. Donahue – American Society of Microbiology

“I ask all microbiologists to make sure that you and your colleagues know what they have in the lab (freezer, refrigerator, store room, etc).”

* Hot Spring Bacteria Can Live Off Invisible Light Alone – Brian Stallard – Nature World News

“Researcher(sic) studying cyanobacteria in hot springs have discovered that the potentially harmful algae can live in near-darkness, absorbing far-red light and converting it into energy while releasing oxygen. “

Insect-borne bacteria destroy ancient Italian olive groves – Tom Kington – GulfNews

“The ancient olive groves of southern Italy, which provide much of the oil the country exports, are being destroyed by deadly, insect-borne bacterium that has already infected nearly half a million trees and has no known cure.”

Uncultured Bacteria (with video) – Serious Science

“Northeastern University Prof. Kim Lewis on great plate count anomaly, siderophores, and human microbiome”

#BacteriaHysteria

* How to Keep Bacteria Out of Your Child’s Lunchbox – FoodSafetyNews

“If possible, a child’s lunch should be stored in a refrigerator during school, but the lid should be left open so that cold air can better circulate and keep the food cold.”

* Chick-fil-A incorporates bacteria-killing copper into restrooms – The News Herald

“Seidel said that Chick-fil-A Owner and Operator Dallas Stoudenmire has realized his responsibility to keep customers bacteria free and is taking the right steps to do so.”

Science and publishing

Concerns Raised Online Linger – Kate Yandell – The Scientist

“The great majority of comments point out some kind of problem,” PubPeer moderators wrote in an e-mail to The Scientist.

Bik’s Picks

Eye implant developed at Stanford could lead to better glaucoma treatments – Bjorn Carey – Stanford News

“A tiny eye implant developed by Stephen Quake’s lab could pair with a smartphone to improve the way doctors measure and lower a patient’s eye pressure.”

Scientists grow an organ in an animal from cells created in lab – Science Daily

“The researchers have created a thymus — an organ next to the heart that produces immune cells known as T cells that are vital for guarding against disease.”

Mozzarella and cheddar are the perfect pizza toppers, according to science – Jenn Harris – LA Times

“Understanding the value of a pie spotted with perfectly crisp cheese, a group of scientists in New Zealand set out to find which cheeses create the perfect topping.”

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Microbiome Digest, August 22, 2014

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The microbiome of the human eye,  chronic lung diseases, ticks, trout, the air in wineries, and Bik’s Picks. Have a good weekend!
Pregnancy and birth

The human microbiome and the great obstetrical syndromes, a new frontier in maternal fetal medicine – Ido Solt – Best Practice & Research Clinical Obstetrics & Gynaecology

“The transmission of maternal microbiomes to the neonate, according to vaginal delivery or cesarean section, is shown to affect health from birth to adulthood.”

Human skin microbiome

Considerations in Understanding the Ocular Surface Microbiome – Michael E. Zegans – American Journal of Ophthalmology

“In ophthalmology, the question naturally arises as to whether or not the ocular surface, like other mucous membrane surfaces, has a resident microbiota, and, if so, what role it plays in ocular surface physiology. This question has provoked much debate over many years. “

Human respiratory microbiome
* The role of the microbiome in exacerbations of chronic lung diseases – Robert P Dickson – The Lancet

“We propose that exacerbations are occasions of respiratory tract dysbiosis—a disorder of the respiratory tract microbial ecosystem with negative effects on host biology.”

Human gut microbiome

* Starving our Microbial Self: The Deleterious Consequences of a Diet Deficient in Microbiota-Accessible Carbohydrates – Erica D. Sonnenburg, Justin L. Sonnenburg – Cell Metabolism

“The low-MAC Western diet results in poor production of gut microbiota-generated short-chain fatty acids (SCFAs), which attenuate inflammation through a variety of mechanisms in mouse models. “

Human vaginal microbiome

Rectal Lactobacillus Species and Their Influence on the Vaginal Microflora: A Model of Male-to-Female Transsexual Women – Ljubomir Petricevic – The Journal of Sexual Medicine

“We undertook this observational study to characterize the Lactobacillus species present in the neovagina and rectum of male-to-female transsexual women and to determine the degree of neovaginal-rectal co-colonization in order to gain a better understanding of the potential role of the gut as a reservoir for genital lactobacilli.”

Animal models of microbiome research

Perinatal antibiotic-induced shifts in gut microbiota have differential effects on inflammatory lung diseases – Shannon L. Russell – Journal of Allergy and Clinical Immunology

“Disease severity was assessed by measuring lung inflammation, pathology, cytokine responses, and serum antibodies. Microbial community analyses were performed on stool samples via 16S ribosomal RNA pyrosequencing and correlations between disease severity and specific bacterial taxa were identified.”

Animal microbiome

The composition and transmission of microbiome in hard tick, Ixodes persulcatus, during blood meal – Xue-Chao Zhang – Ticks and Tick-borne Diseases

“By 16S rRNA Illumina sequencing, we investigated the microbiome of I. persulcatus and assessed the variation of the microbiome before and after blood feeding.”

Diet type dictates the gut microbiota and the immune response against Yersinia ruckeri in rainbow trout (Oncorhynchus mykiss) – Hans-Christian Ingerslev – Fish & Shellfish Immunology

“This study investigated the influence of the rainbow trout (Oncorhynchus mykiss) commensal intestinal microbiota in connection to an experimental Yersina ruckeri infection, the causative agent of enteric redmouth disease.”

Food microbiology

* Microbial communities in air and wine of a winery at two consecutive vintages – Fátima Pérez-Martín – International Journal of Food Microbiology

“The microbial composition was determined by using both a culture-dependent method and a culture-independent method, PCR-denaturing gradient gel electrophoresis (PCR-DGGE).”

Metabolomics

* Microbial catabolism of procyanidins by human gut microbiota – Keqin Ou – Molecular Nutrition & Food Research

“The objective of this study was to identify and quantify the microbial metabolites of procyanidins after anaerobic fermentation with human microbiota.”

Bioinformatics

* Defining the Estimated Core Genome of Bacterial Populations Using a Bayesian Decision Model – Andries J. van Tonder – PLOS Computational Biology

“The aim of our study was to develop a model to estimate the bacterial core genome from next-generation whole genome sequencing data and use this model to identify novel genes associated with important biological functions. “

* Comparative Analysis of Functional Metagenomic Annotation and the Mappability of Short Reads – Rogan Carr, Elhanan Borenstein – PLOS ONE

“Overall, our findings provide a first comprehensive evaluation of the capabilities and limitations of functional metagenomic annotation, providing crucial goal-specific best-practice guidelines to inform future metagenomic research.”

ExaBayes: Massively Parallel Bayesian Tree Inference for the Whole-Genome Era
Andre J. Aberer – Molecular Biology and Evolution

“We introduce a novel, user-friendly software package engineered for conducting state-of-the-art Bayesian tree inferences on datasets of arbitrary size.”

Microbes in the news

Behold 50 shades of Gross: A guide to Germaphobia! – Katherine Dahlhausen – MicroBEnet

“So logically, I began researching germaphobic practices. Some of them are just too good not to share! “

California Trees Nailed As The Source Of Mystery Infections – Nancy Shute – NPR

“”We had a good idea that the fungus was going to be associated with trees,” says Deborah Springer, a postdoctoral fellow at Duke University who studies C. gatti. “

Bik’s Picks

Pulling teeth from history: DNA from ancient teeth can help to yield information about our ancestors’ health, diet and diseases – Philip Hunter – EMBO Reports

“Teeth have proven to be an excellence source of ancient DNA. New analytical tools are helping to exploit this treasure trove to address questions about the link between diet and health, and the impact of historical epidemics with clear relevance for human health today.”

Ten Simple Rules of Live Tweeting at Scientific Conferences – Sean Ekins, Ethan O. Perlstein – PLOS Computational Biology

“Increasingly, some scientists are using Twitter as a vehicle to summarize presentations and posters at conferences in real time, which is defined as “live tweeting.””

Why the World Smells Different After It Rains – Behold, the wonders of petrichor.
Megan Garber – The Atlantic

“In the video above, PBS’s Joe Hanson describes the biology that leads to petrichor.”

Scientist Mistakenly Does “Dry-Ice Bucket Challenge” – The Allium

“Sad news has come to us today at The Allium, when we learned that scientist Dr. Liv Good, has mistakenly carried out a Dry-Ice Bucket challenge.”

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Microbiome digest, August 20, 2014

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Ocular microbiome, life under ice, and gut microbiome and behavior.

Human ocular microbiome

Assessment of ocular surface microbiota in keratoconus patients – a pilot study – M Gajecka – Acta Ophthalmologica

“Culture-based microbiology methods are used in the investigation to preliminary examine the OS microbiota. Simultaneously, microbial genetic material is extracted from the eye swabs for further qualitative and quantitative analyzes using molecular biology methods (real-time PCR, NGS).”

Microbial detection in clinical samples

Elevated Levels of Circulating DNA in Cardiovascular Disease Patients: Metagenomic Profiling of Microbiome in the Circulation – Vasudevan Dinakaran – PLOS ONE

“This work was aimed to study the circulating human microbiome in CVD patients and healthy subjects.”

Animal models of microbiome

A Possible Link between Food and Mood: Dietary Impact on Gut Microbiota and Behavior in BALB/c Mice – Bettina Pyndt Jørgensen – PLOS ONE

“Behavioral changes were accompanied by a significant change in GM composition of mice fed a high-fat diet” “Denaturation gradient gel electrophoresis (DGGE) was used to investigate differences in the composition of the GM.”

Mammalian microbiome

Metagenomic identification of novel enteric viruses in urban wild rats and genome characterization of a group A rotavirus – Jana Sachsenröder – Journal of General Virology

“Here, intestinal contents from 20 wild Norway rats (Rattus norvegicus) collected in the city of Berlin, Germany, were subjected to metagenomic analysis of viral nucleic acids.”

Water microbiome

A microbial ecosystem beneath the West Antarctic ice sheet – Brent C. Christner – Nature

“Heterotrophic and autotrophic production data together with small subunit ribosomal RNA gene sequencing and biogeochemical data indicate that SLW is a chemosynthetically driven ecosystem inhabited by a diverse assemblage of bacteria and archaea. “

See also: Lakes under the ice: Antarctica’s secret garden – Douglas Fox – Nature

“Samples from a lake hidden under 800 metres of ice contain thousands of microbes and hint at vast ecosystems yet to be discovered.”

Bioinformatics

A Rank-Based Sequence Aligner with Applications in Phylogenetic Analysis – Liviu P. Dinu – PLOS ONE

“This paper introduces a method for assigning a set of short DNA reads to a reference genome, under Local Rank Distance (LRD). The rank-based aligner proposed in this work aims to improve correctness over speed. “

Viruses and phages (see also the rat/rotavirus paper above)

Unveiling viral–host interactions within the ‘microbial dark matter’ – Manuel Martínez-García – Nature Communications

“Using this method, we pinpoint viruses infecting the ubiquitous hyperhalophilic Nanohaloarchaeota, included in the so-called ‘microbial dark matter’ (the uncultured fraction of the microbial world).”

Microbes in the news

Archiving: Don’t let microbial samples perish – Noah Fierer and Craig Cary – Nature

“Microbial ecologists must coordinate to archive sample collections and genetic material.”

Microbiology: Microbiome science needs a healthy dose of scepticism – William P. Hanage – Nature

“To guard against hype, those interpreting research on the body’s microscopic communities should ask five questions”

Science, publishing and career

Editorial: Finding the root – The NIH is right to investigate whether bias makes grant awards unfair – Nature

“The idea that scientists who volunteer time and energy to review NIH grants could be biased against qualified minority researchers is a tough pill to swallow. “

Today’s YAMMM (Yet another mostly male meeting): pharma-nutrition #PN2015 – Jonathan Eisen – The Tree of Life

“Yay.  All men.  How wonderful.  Because, you know, there are no women working on the microbiome and nutrition right?  Ugg. “

 

Equally productive women are tenured less -Beryl Lieff Benderly – Science

“Women received tenure less often than men with equal productivity in three disciplines studied by Kate Weisshaar, a Ph.D. student in sociology at Stanford University.”

Bik’s Picks

Solar energy that doesn’t block the view – Science Daily

“Researchers have developed a new type of solar concentrator that when placed over a window creates solar energy while allowing people to actually see through the window. “

If Seals Hadn’t Introduced Tuberculosis To The New World, Europeans Would Have – Science 2.0

“A new study documents that again, finding isolated Mycobacterium pinnipedii from skeletons found in Peru which are at least 1000 years old. The pathogen is a relative of the TB bacterium that affects seals, so it likely that seals carried the pathogens from Africa to the Peruvian coast.”

Which Hot New Lab Coat Should You Buy This Season? – Fake Science

“We’ve found the hottest coats from Paris, Milan, and Batavia, Illinois and put them into our patented quiz. Take it and find out which lab coat will have you steaming up the beakers!”

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Microbiome digest, August 17, 2014

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

Human gut microbiome

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

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

Animal microbiome

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

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

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

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

Plant microbiome

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

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

Soil microbiome

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

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

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

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

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

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

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

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

Water microbiome

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

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

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

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

Metagenomics

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

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

Metabolomics

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

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

Bioinformatics

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

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

Microbes in the news

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

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

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

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

Bik’s Picks

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

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

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

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

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

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

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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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General microbiology and science, August 5, 2014

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Antibiotic resistance, phages, bioinformatics tools, and how to present your research in 3 minutes.

Antibiotic resistance

The Natural Environment May Be the Most Important Source of Antibiotic Resistance Genes – Desmond Keith O’Toole – mBio

“I found the recent paper by Wichmann et al. (1) of great interest, and it illustrates an aspect of antibiotic resistance that has concerned me for a long time, namely, the origin of that resistance.”

Phages and viruses

Pervasive domestication of defective prophages by bacteria – Louis-Marie Bobay, Marie Touchon, and Eduardo P. C. Rocha – PNAS USA

“We identified over 300 vertically inherited prophages within enterobacterial genomes. Some of these elements are very old and might predate the split between Escherichia coli and Salmonella enterica. “

Bioinformatics tools

MaxBin: an automated binning method to recover individual genomes from metagenomes using an expectation-maximization algorithm – Yu-Wei Wu, Yung-Hsu Tang, Susannah G Tringe, Blake A Simmons and Steven W Singer – Microbiome

“We have developed a binning algorithm, MaxBin, which automates the binning of assembled metagenomic scaffolds using an expectation-maximization algorithm after the assembly of metagenomic sequencing reads.”

Fast and Sensitive Alignment of Microbial Whole Genome Sequencing Reads to Large Sequence Datasets on a Desktop PC: Application to Metagenomic Datasets and Pathogen Identification – Lőrinc S. Pongor – PLOS ONE

“We have developed Taxoner, an open source, taxon assignment pipeline that includes a fast aligner (e.g. Bowtie2) and a comprehensive DNA sequence database. “

More microbes

Transient Darwinian selection in Salmonella enterica serovar Paratyphi A during 450 years of global spread of enteric fever – Zhemin Zhou, Angela McCann, François-Xavier Weill, Camille Blin, Satheesh Nair, John Wain, Gordon Dougan, and Mark Achtman – PNAS

“We identified seven modern lineages among 149 genomes on the basis of 4,584 SNPs in the core genome and estimated that Paratyphi A originated 450 y ago. “

Bacillus subtilis chromosome organization oscillates between two distinct patterns – Xindan Wang, Paula Montero Llopis, and David Z. Rudner – PNAS USA

“We propose that the distinct organization patterns observed for bacterial chromosomes reflect a common organization–segregation mechanism, and that simple modifications to it underlie the unique patterns observed in different species.”

Microbes in the news

Researchers Find Surprises in Human Microbiome – Carol Potera – BioScience

But “some forms of autism may have an etiology that lies in the gut, not the brain,” says Sarkis Mazmanian of the California Institute of Technology.

Science and publishing

Science Speak – Rina Shaikh-Lesko – The Scientist

“Contests that challenge young scientists to explain their research without jargon are turning science communication into a competitive sport.”

Researcher’s death shocks Japan – David Cyranoski – Nature Newsblog

“Yoshiki Sasai, one of Japan’s top stem-cell researchers, died this morning (5 August) in an apparent suicide. “

Bik’s Picks

The color red distorts time perception for men, but not for women – Masahiro Shibasaki & Nobuo Masataka – Nature Scientific Reports

“The results showed that the perceived duration of a red screen was longer than was that of a blue screen. However, the results reflected sex differences; men, but not women, overestimated the duration of the red screen. “

Gray’s paradox: A fluid mechanical perspective – Rahul Bale, Max Hao, Amneet Pal Singh Bhalla, Namrata Patel & Neelesh A. Patankar – Nature Scientific Reports

“Nearly eighty years ago, Gray reported that the drag power experienced by a dolphin was larger than the estimated muscle power – this is termed as Gray’s paradox. We provide a fluid mechanical perspective of this paradox.”

 

Total darkness at night key to success of breast cancer therapy, study shows – Science Daily

“Exposure to light at night, which shuts off nighttime production of the hormone melatonin, renders breast cancer completely resistant to tamoxifen, a widely used breast cancer drug, says a new study. “

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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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