General microbiology and science, September 29, 2014

Metabolomics, metagenomics, OTU binning, DNA extraction for metagenomics, RNAseq, life without water, microbes and art, and Bik’s Picks.

Metabolomics

A Peptide-Based Method for 13C Metabolic Flux Analysis in Microbial Communities – Amit Ghosh – PLOS Computational Biology

“Here we propose a new type of 13C MFA that infers fluxes based on peptide labeling, instead of amino acid labeling. “

Metabolic fingerprint of dimethyl sulfone (DMSO2) in microbial-mammalian co-metabolism – Xuan He and Carolyn Marie Slupsky – Journal of Proteome Research

“Here, we review a metabolic pathway that integrates the microbial catabolism of methionine with mammalian metabolism of methanethiol (MT), dimethyl sulfide (DMS) and dimethyl sulfoxide (DMSO)”

Metagenomics

Metagenomic epidemiology: a new frontier – Stephen S Francis, Lee W Riley – Journal of Epidemiology and Community Health

“In this commentary we hope to briefly summarise studies into the bacterial and viral microbiome and how this shifting paradigm affects epidemiology.“

Phages and viruses

Viral attack exacerbates the susceptibility of a bloom-forming alga to ocean acidification – Shanwen Chen – Global Change Biology

“..when the harmful bloom alga Phaeocystis globosa is infected with viruses under future ocean conditions, its photosynthetic performance further decreased and cells became more susceptible to stressful light levels..”

Ecology / Bioinformatics

Limits to robustness and reproducibility in the demarcation of operational taxonomic units – Thomas S. B. Schmidt – Environmental Microbiology

“Using a global data set of 887 870 bacterial 16S rRNA gene sequences, we objectively quantified biases introduced by several widely employed sequence clustering algorithms. “

Techniques

* DNA extraction protocols cause differences in 16S rRNA amplicon sequencing efficiency but not in community profile composition or structure – Benjamin E. R. Rubin – MicrobiologyOpen

“While bacterial community composition recovered using Illumina 16S rRNA amplicon sequencing was not detectably biased by any method, the quantity of bacterial DNA varied drastically, reducing the number of samples that could be amplified and sequenced. “

Protocols for metagenomic DNA extraction and Illumina amplicon library preparation for faecal and swab samples – A.-T. E. Vo1 and J. A. Jedlicka – Molecular Ecology Resources

“We developed and tested a novel metagenomic DNA extraction approach using solid phase reversible immobilization (SPRI) beads on Western Bluebird (Sialia mexicana) samples stored in RNAlater.”

Caught in the act: RNA-Seq provides novel insights into mRNA degradation – Jan Gerwig and Jörg Stülke – Molecular Microbiology

“In MolecularMicrobiology, Liu et al. (2014) have analysed RNA processing by polynucleotide phosphorylase, the major 3′–5′ exonuclease in Bacillus subtilis.”

3D genome reconstruction from chromosomal contacts – Annick Lesne – Nature Methods

“We propose a two-step algorithm, ShRec3D, and assess its accuracy using both in silico data and human genome-wide 3C (Hi-C) data.”

More microbiology

Multiplication of microbes below 0.690 water activity: implications for terrestrial and extraterrestrial life – Andrew Stevenson – Environmental Microbiology

“We discuss water activity in relation to the limits of Earth’s present-day biosphere; the possibility of microbial multiplication by utilizing water from thin, aqueous films or non-liquid sources;”

Microbes in the News

Scientists sniffing out the Western allergy epidemic – BBC News

“Both families gamely agreed to provide bacterial swabs of their skin, guts and even their homes in the hope they might offer clues about why they suffer from allergies.”

Study looks at bacteria on a plane – CNN Wire

“A study by Auburn University looked at how long two potentially deadly bacteria, e-coli and MRSA, can live on airline surfaces. They checked things like toilet handles, tray tables and seat pockets.”

Bacteria in wine may bring health benefits – LiveScience – Agata Blaszczak Boxe

“In the study, researchers in Spain isolated 11 strains of bacteria from wine, including strains of Lactobacillus, which are also found in yogurt, as well as Oenococcus and Pediococcus bacteria, which are associated with the wine-making process.”

A gut feeling: Bacteria like that found in yoghurt may have helped shape our personalities and made us who we are – Alex Finnis – Daily Mail UK

“Bacteria in our stomachs can affect our brain chemistry, scientists have discovered – which means eating yoghurt could help us be happier.

Science and Art

Should Silicon Valley Hire Microbes? – Glenn McDonald – Discovery

“It’s an art installation slated to launch October 21 at San Francisco’s Modernism Gallery. The event will feature the official certification of approximately 100 billion bacteria in areas including product development and finance. “

Octopus bacteria lights up this installation – Liat Clark – Wired UK

“A designer has harvested bacteria from an octopus to create a bioluminescent installation that lights up when it is moved.”

Photographer Immerses His Film in Live Bacteria for Years to Create Unique Portraits – Gannon Burgett – PetaPixel

“Over the course of a few weeks, months or years, the microbes destabilize and eat away at the silver halide particles in the emulsion.”

Bik’s Picks

Dolphins are attracted to magnets: Add dolphins to the list of magnetosensitive animals, French researchers say – Science Daily

“Dolphins are indeed sensitive to magnetic stimuli, as they behave differently when swimming near magnetized objects.”

Science explains why volcanoes are erupting all over the place right now – Robin Wylie – Washington Post

“The Earth seems to have been smoking a lot recently. Volcanoes are erupting in Iceland, Hawaii, Indonesia, Ecuador and Mexico right now. “

Scientists find tiny, poisonous new mystery frog – Andrew Griffin – Independent

“Scientists have discovered a new species of poison dart frog, small enough to fit on a fingernail but still bearing the toxic poison that gives the frogs their name.”

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General microbiome and science, June 30

Monday is always a busy day, so lots of papers today. Phages, CRISPRs, antibiotic resistance, probiotics, archaea, biofilms and a Goldilocks planet.

Antibiotics and resistance

Horizontal gene transfer in the human gastrointestinal tract: potential spread of antibiotic resistance genes – JR Huddleston – Infection and Drug Resistance

“This review aims to give an overview of the major horizontal transfer mechanisms and their evolution and then demonstrate the human lower gastrointestinal tract as an environment in which horizontal gene transfer of resistance determinants occurs.”

Screen shot 2014-06-30 at 06.47PM, Jun 30Bacterial persisters: formation, eradication, and experimental systems
Sophie Helaine, Elisabeth Kugelberg – Trends in Microbiology

“Toxin–antitoxin (TA) modules have an important role in the formation of persisters and several studies show that they can form in response to different triggers.”

Screen shot 2014-06-30 at 06.48PM, Jun 30Antibiotic Treatment Suppresses Rotavirus Infection and Enhances Specific Humoral Immunity – Robin Uchiyama – Journal of Infectious Diseases

“Microbiota ablation resulted in reduced rotavirus infection/diarrhea and a more durable rotavirus antibody response, suggesting that antibiotic administration before rotavirus vaccination could raise low seroconversion rates that correlate with the vaccine’s inefficacy in developing regions.”

And:  Antibiotics Help Control Rotavirus Infections and Enhance Antirotaviral Immunity: Are You Serious? – Luther A. Bartelt and Richard L. Guerrant – Journal of Infectious Diseases

“Yes, we must understand intriguing new findings; but no, we are far from serious about widespread use of antimicrobials with routine immunizations.”

Screen shot 2014-06-30 at 06.44PM, Jun 30Transferrin Iron Starvation Therapy for Lethal Bacterial and Fungal Infections – Lin Lin – Journal of Infectious Diseases

“These results provide proof of principle that bacterial infections can be treated in vivo by attacking host targets (ie, trace metal availability) rather than microbial targets.”

Bacterial detection in blood and other sites

Screen shot 2014-06-30 at 06.45PM, Jun 30Identification of pathogens from blood culture bottles in spiked and clinical samples using matrix-assisted laser desorption ionization time-of-flight mass-spectrometry analysis – Simone Konnerth – BMC Research Notes

“MALDI-TOF MS using the SARAMIS database was applied to 37 spiked blood culture samples. Identification rates of spiked samples were as follows: The species level was determined in 16 of 21 (76.2%) Gram negative bacteria and in 11 of 13 (84.6%) Gram positive bacteria. “

Infection and host response

Type I and III Interferon Production in Response to RNA Viruses – Elizabeth Reid and Bryan Charleston – Journal of Interferon & Cytokine Research

“There are now many examples of RNA viruses inducing type I and type III IFNs, and although these IFNs act through different receptors, in many systems studied, they induce a similar spectrum of genes. “

CRISPRs

Screen shot 2014-06-30 at 06.50PM, Jun 30Review: Adapting to new threats: the generation of memory by CRISPR-Cas immune systems – Robert Heler – Molecular Microbiology

“Recent studies have begun to elucidate the genetic requirements for adaptation and have demonstrated that rather than being a stochastic process, the selection of new spacers is influenced by several factors. We review here our current knowledge of the CRISPR adaptation mechanism”

Screen shot 2014-06-30 at 06.53PM, Jun 30The three major types of CRISPR-Cas systems function independently in CRISPR RNA biogenesis in Streptococcus thermophilus – Jason Carte – Molecular Microbiology

“Our findings indicate that multiple CRISPR-Cas systems can function independently in crRNA biogenesis within a given organism – an important consideration in engineering coexisting CRISPR-Cas pathways”

Viruses and phages

Screen shot 2014-06-30 at 06.53PM, Jun 30Exploiting gut bacteriophages for human health – Marion Dalmasso – Trends in Microbiology

“We emphasise the complexity and individuality of the phageome, and the link to the health state of the host. We highlight the practical applications of bacteriophages in medicine and in the food chain.”

Screen shot 2014-06-30 at 06.52PM, Jun 30Environmental bacteriophages : viruses of microbes in aquatic ecosystems – Télesphore Sime – Ngando – Frontiers in Microbiology

“The present chapter sought to review the literature on the diversity and functional roles of viruses of microbes in environmental microbiology, focusing primarily on prokaryotic viruses (i.e. phages) in aquatic ecosystems, which form the bulk of our knowledge in modern environmental viral ecology.”

Archaea

Screen shot 2014-06-30 at 06.55PM, Jun 30Taxonomic database and cut-off value for processing mcrA gene 454 pyrosequencing data by MOTHUR – Sizhong Yang – Journal of Microbiological Methods

“The functional mcrA gene of methanogens can generate phylogeny as congruent as the 16S rRNA gene phylogeny. “

Screen shot 2014-06-30 at 06.59PM, Jun 30Biofilm formation of mucosa-associated methanoarchaeal strains
Corinna Bang – Frontiers in Microbiology

“Here, the ability of three methanoarchaeal strains, Methanobrevibacter smithii and Methanosphaera stadtmanae, which form part of the human gut microbiota, and the Methanosarcina mazei strain Gö1 to grow on different surfaces and form biofilms was investigated.”

Biofilms (see also Archaea above and Probiotics below)

Screen shot 2014-06-30 at 07.02PM, Jun 30Development of an in vitro periodontal biofilm model for assessing antimicrobial and host modulatory effects of bioactive molecules
Emma Millhouse – BMC Oral Health

Multi-species biofilms were either treated with either molecule, or alternatively epithelial cells were treated with these prior to biofilm co-culture. Biofilm composition was evaluated and inflammatory responses quantified at a transcriptional and protein level.

Probiotics

Screen shot 2014-06-30 at 06.43PM, Jun 30Review: Enumeration of probiotic strains: Review of culture-dependent and alternative techniques to quantify viable bacteria – Catherine Davis – Journal of Microbiological Methods

“Consensus on an operational definition of viability and systematic efforts to validate these alternative techniques ultimately will strengthen the accuracy and reliability of probiotic strain enumeration.”

Inhibitory effect of Lactobacillus salivarius on Streptococcus mutans biofilm formation
Chien-Chen Wu – Molecular Oral Microbiology

“We analyzed 64 L. salivarius strains and found that two, K35 and K43, significantly inhibited S. mutans biofilm formation with inhibitory activities more pronounced than those of Lactobacillus rhamnosus GG (LGG), a prototypical probiotic that shows anti-caries activity.

General taxonomy and phylogeny

Screen shot 2014-06-30 at 07.04PM, Jun 30Considering external information to improve the phylogenetic comparison of microbial communities: a new approach based on constrained Double Principal Coordinates Analysis (cDPCoA) – S Dray – Molecular Ecology Resources

“In this work, we extend DPCoA to integrate the information of external variables measured on communities. The constrained Double Principal Coordinates Analysis (cDPCoA) is able to enforce a priori classifications to retrieve subtle differences and(or) remove the effect of confounding factors. “

Screen shot 2014-06-30 at 06.43PM, Jun 30Understanding molecular identification and polyphasic taxonomic approaches for genetic relatedness and phylogenetic relationships of microorganisms – Surajit Das – Journal of Microbiological Methods

“In this regard, a polyphasic taxonomic approach is advantageous because it exploits simultaneously both conventional as well as molecular identification techniques.”

Metabolomics

Screen shot 2014-06-30 at 07.01PM, Jun 30Nutrient sharing in the microbial world – Erica C. Seth and Michiko E. Taga – Frontiers in Microbiology

“Cofactor cross-feeding can contribute to both the health and nutrition of a host organism, the virulence and persistence of pathogens, and the composition and function of environmental communities. “

Metagenomics

Combination of Metagenomics and Culture Based Methods to Study the Interaction Between Ochratoxin A and Gut Microbiota – Mingzhang Guo – Toxicological Sciences

“Changes in functional genes of gut microbiota including signal transduction, carbohydrate transport, transposase, amino acid transport system and mismatch repair were observed.”

Chromosomal organization

NuChart-II: a graph-based approach for the analysis and interpretation of Hi-C data (PDF) – Fabio Tordini – Proceedings of the CIBB 2014

“NuChart-II is a highly optimized implementation of a previous prototype package developed in R, in which the graph-based representation of Hi-C data was tested, but that also showed inevitable problems of scalability while working genome-wide on large datasets.”

Science and education

Screen shot 2014-06-30 at 06.58PM, Jun 30Starting small: using microbiology to foster scientific literacy
Amy F. Savage, Brooke A. Jude – Trends in Microbiology

“In order to achieve scientific literacy for all students, Bard College recently implemented Citizen Science, a common January course for all first-year students. Structured around the question ‘how do we reduce the global burden of disease?’, this course uses microbiological tools to develop an understanding of potential answers.”

 

Dr. Bik’s Picks

Screen Shot 2014-07-01 at 12.06.17 AMBird brains: Public asked to look out for clever rooks – Victoria Gill – BBC News

“The British Trust for Ornithology (BTO) is asking the public to take part in a national survey of bird intelligence. From 1 July, the charity is asking people to submit video clips or descriptions of the behaviour or rooks – some of our cleverest garden birds.”

Screen Shot 2014-07-01 at 12.06.52 AMPotentially habitable Earth-like planet discovered; May have similar temperatures to our planet – Science Daily

“A potentially habitable Earth-like planet that is only 16 light years away has been discovered. The “super-Earth” planet, GJ 832 c, takes 16 days to orbit its red-dwarf star, GJ 832, and has a mass at least five times that of Earth.”

Screen Shot 2014-07-01 at 12.07.35 AMStudy Implicates Smog In Autism And Schizophrenia – Science 2.0

“A recent paper found that exposure to air pollution early in life produces harmful changes in the brains of mice, including an enlargement of part of the brain that is seen in humans who have autism and schizophrenia, and that led them to conclude that smog causes autism.”

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General microbiology and science, June 18

Learn about dengue at the World Cup, a deadly lake, 3D structures of genomes, OTUs and tables, musical kids, and why your iPhone headphones are always in a knot.

Dengue

Evaluation of single-round infectious, chimeric dengue type 1 virus as an antigen for dengue functional antibody assays – Atsushi Yamanaka – Vaccine

“In the present study, SRIPs of DENV-1 (D1-SRIPs) were evaluated as an antigen for functional antibody assays.”

An inhibition model of BPTI to unlinked dengue virus NS2B-NS3 protease – Hua Li – FEBS Letters

“BPTI shows strong competitive inhibitory activity (Ki = 6.5 nM) against this unlinked protease, which adopts a closed conformation.”

The role of cell proteins in dengue virus infection – Ma. Isabel Salazar – Journal of Proteomics

“This review focuses on recent reports about cellular proteins involved along the dengue virus replication cycle, in prime cellular targets during the infection of both humans and mosquito hosts and also on the proteomics and other approaches that are being used to reveal the entire orchestration and most significant processes altered during infection.”

Dengue outlook for the World Cup in Brazil – Eduardo Massad – The Lancet Infectious Diseases

Correspondence on: Dengue outlook for the World Cup in Brazil: an early warning model framework driven by real-time seasonal climate forecasts

Arsenic metabolism

43,000 die annually in Bangladesh: Study – The Daily Star

“This rate is 25 percent all over Bangladesh, said Dr Kazi Matin Ahmed, geology professor of Dhaka University. He presented the paper at a seminar titled “Arsenic Activities, Research and Outcomes” organised by the Bangladesh Medical Research Council (BMRC) in its auditorium in the capital yesterday.”

Arsenic speciation in rice-based food for adults with celiac disease – Sandra Munera-Picazo – Food Additives and Contaminants

“…the objective of this study was to analyze the occurrence of arsenic (As) in gluten-free products, basically those rice-based, intended for celiac adult consumers.”

Could This Acid Lake Hold the Elixir of Life for Cancer Patients? – Ryot.org

“The Berkeley Acid Pit is a giant hole filled with arsenic and sulfuric acid, and has a history of causing disturbing deaths… and it’s making its way into the city’s water supply, according to PitWatch.”

Chromosomal Organization

Targeted chromatin capture (T2C): a novel high resolution high throughput method to detect genomic interactions and regulatory elements – Petros Kolovos – Epigenetics &

“We applied T2C on well-known model regions, the mouse beta-globin locus and the human H19/IGF2 locus. In both cases we identified all known chromatin interactions”

A statistical approach for inferring the 3D structure of the genome – Nelle Varoquaux – Bioinformatics

“We propose a novel approach to infer a consensus 3D structure of a genome from Hi-C data. The method incorporates a statistical model of the contact counts, assuming that the counts between two loci follow a Poisson distribution whose intensity decreases with the physical distances between the loci.”

Spatial organization of interphase chromosomes and the role of chromatin fibril dynamics in the positioning of genome elements – E. S. Gushchanskaya – Molecular Biology

In this review, we discuss the results of these projects, which allow us to explain the functional basis of nucleus multilevel compartmentalization and to identify the principles of high-level chromatin organization. “

Computational ecology

A fast and unbiased procedure to randomize ecological binary matrices with fixed row and column totals – Giovanni Strona – Nature Communications

“A well-known problem in numerical ecology is how to recombine presence-absence matrices without altering row and column totals. “

Consistent, comprehensive and computationally efficient OTU definitions – Jai Ram Rideout – PeerJ PrePrints

“We present a performance-optimized algorithm, subsampled open-reference OTU picking, for assigning marker gene (e.g., 16S rRNA) sequences generated on next-generation sequencing platforms to operational taxonomic units (OTUs) for microbial community analysis.”

 

Bacteria in blood and sterile sites

Rapid and direct MALDI-MS identification of pathogenic bacteria from blood using ionic liquid-modified magnetic nanoparticles (Fe3O4@SiO2) – Mukesh L. Bhaisare – Journal of Materials Chemistry B

“A novel method for pathogenic bacteria identification directly from blood samples using cationic ionic liquid-modified magnetic nanoparticles (CILMS) is reported.”

Metagenomics

GroopM: An automated tool for the recovery of population genomes from related metagenomes – Michael Imelfort – PeerJ PrePrints

“Here we introduce GroopM, an automated binning tool that primarily uses differential coverage to obtain high fidelity population genomes from related metagenomes. “

DNA-dependent RNA polymerase detects hidden giant viruses in published databanks – Vikas Sharma – Genome Biology and Evolution

“To explore the dark matter, we used viral RNAP2 and reconstructed putative ancestral RNAP2, which were significantly superior in detecting distant clades than current sequences, and we revealed two additional unknown mimiviruses, misclassified as an euryarchaeote and a oomycete plant pathogen, and detected unknown putative viral clades”

Metabolomics

Comparative Metabolomics and Structural Characterizations Illuminate Colibactin Pathway-Dependent Small Molecules – Maria I. Vizcaino – Journal of the American Chemical Society

“Here we implemented a comparative metabolomics and targeted structural network analyses approach to identify a catalog of small molecules dependent on the colibactin pathway from the meningitis isolate E. coli IHE3034 and the probiotic E. coli Nissle 1917.”

Scientific writing and publishing

Screen Shot 2014-06-18 at 11.01.34 PMColour blindness: Still too many red–green figures – S. Colby Allred – Nature

“People with red–green colour blindness cannot interpret figures in research papers that use these colours. We call for all journals to provide alternative versions of figures that are more accessible to such individuals.”

Open access: Sharing your data is easier than you think – Stephen Eglen – Nature

“Storing large volumes of raw data is costly, but many items destined for sharing are highly processed and relatively small. “

Dr. Bik’s Picks

The Irish potato famine pathogen Phytophthora infestans originated in central Mexico rather than the Andes – Erica M. Goss – PNAS

“We sequenced four nuclear genes in representative samples from Mexico and the South American Andes. An Andean origin of P. infestans does not receive support from detailed analyses of Andean and Mexican populations. “

Behavioral and Neural Correlates of Executive Functioning in Musicians and Non-Musicians – Jennifer Zuk – PLOS ONE

“Overall, musicians show enhanced performance on several constructs of EF, and musically trained children further show heightened brain activation in traditional EF regions during task-switching.”

There’s a scientific reason your iPhone headphones are always tangled – Fiona MacDonald – Science Alert

“But between 46 centimeters and 150 centimeters (about five feet), the probability of a knot forming rises dramatically.”

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More microbiology and science, June 2, 2014

Dengue and humidity, bacteria from Mars, sequencing, and aspartame.

Dengue

Microbes in Space

Sequencing and bioinformatics

Chromosome organization

Arsenic metabolism

Dr. Bik’s Picks

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