Category Archives: Techniques

Microbiome digest, November 12, 2014

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Another short installment of the Digest. Two studies on microbial DNA contamination in reagents and laboratories, and gut microbiome in Down Syndrome.
Human gut microbiome

* Gut Microbiome in Down Syndrome – Elena Biagi – PLOS ONE

* Superresolution Imaging Captures Carbohydrate Utilization Dynamics in Human Gut Symbionts – Krishanthi S. Karunatilaka – mBio

Microbiota Talks Cholera out of the Gut – Amanda J. Hay, Jun Zhu – Cell Host & Microbe

 

Animal microbiome

Comparative Metagenomic Analysis of Coral Microbial Communities Using a Reference-Independent Approach – Camila Carlos – PLOS ONE

The Effect of Antibiotics on Associated Bacterial Community of Stored Product Mites – Jan Kopecky – PLOS ONE

 

Metagenomic Insights into the RDX-Degrading Potential of the Ovine Rumen Microbiome – Robert W. Li – PLOS ONE

Plant microbiome

Functional Potential of Soil Microbial Communities in the Maize Rhizosphere – Xiangzhen Li – PLOS ONE

* Genome-wide association study of Arabidopsis thaliana leaf microbial community – Matthew W. Horton – Nature Communications

Environmental microbiome

A method for sampling microbial aerosols using high altitude balloons – N.C. Bryan – Journal of Microbiological Methods

Techniques

(preprint already featured here in July, but now officially out)
* Reagent and laboratory contamination can critically impact sequence-based microbiome analyses – Susannah J Salter – BMC Biology

* Diverse and Widespread Contamination Evident in the Unmapped Depths of High Throughput Sequencing Data – Richard W. Lusk – PLOS ONE

 

Reconceptualising the beta diversity-environmental heterogeneity relationship in running water systems – Jani Heino – Freshwater Biology

Microbes in the news

* Contaminomics: Why Some Microbiome Studies May Be Wrong – Ed Yong – National Geographic

* The Kitome: Dealing with the reagent microbiome – Pat Schloss – Mothur.org

DNA Extraction Kits Contaminated – Kerry Grens – The Scientist

Bik’s Picks

Serotonin lies at the intersection of pain and itch – Bethany Brookshire – ScienceNews

Rainbow palette found in Brooklyn’s contaminated water – Aviva Rutkin – New Scientist

This did not work on my cats, but feel free to try:
‘Cat Circles’, The Amazing Phenomenon In Which a Cat Will Always Sit Inside a Circle on the Floor – Lori Dorn – Laughing Squid

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Microbiome digest, November 11, 2014

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Human oral microbiome

Physiological Adaptations of Key Oral Bacteria – C. W. Ian Douglas – Advances in Microbial Physiology

Human gut microbiome

Development and Survival of Th17 Cells within the Intestines: The Influence of Microbiome- and Diet-Derived Signals – Joseph H. Chewning – The Journal of Immunology

Gut Inflammation and Immunity: What Is the Role of the Human Gut Virome? – Alfredo Focà – Mediators of Inflammation

Animal microbiome

Faecal Microbiota of Forage-Fed Horses in New Zealand and the Population Dynamics of Microbial Communities following Dietary Change – Karlette A. Fernandes – PLOS ONE

The Effect of Phytochemical Tannins-Containing Diet on Rumen Fermentation Characteristics and Microbial Diversity Dynamics in Goats Using 16S rDNA Amplicon Pyrosequencing – B. R. Min – Agriculture, Food & Analytical Bacteriology

Microbial diversity in forestomach and caecum contents of the greater long-tailed hamster Tscherskia triton (Rodentia: Cricetidae) – Akio Shinohara – Mammalian Biology – Zeitschrift für Säugetierkunde

The pathogen Batrachochytrium dendrobatidis disturbs the frog skin microbiome during a natural epidemic and experimental infection – Andrea J. Jani – PNAS USA

Gill bacteria enable a novel digestive strategy in a wood-feeding mollusk – Roberta M. O’Connor – PNAS USA

Arbuscular mycorrhizal fungi communities in a coral cay system (Morrocoy, Venezuela) and their relationships with environmental variables – M.M. Alguacil – Science of the Total Environment

Soil microbiome

Short-term parasite-infection alters already the biomass, activity and functional diversity of soil microbial communities – Jun-Min Li – Scientific Reports

Impact of short-term storage temperature on determination of microbial community composition and abundance in aerated forest soil and anoxic pond sediment samples – Franziska B. Brandt – Systematic and Applied Microbiology

Seasonal influence of climate manipulation on microbial community structure and function in mountain soils – Jérémy Puissant – Soil Biology and Biochemistry

Effect of organic and conventional practices on carbon-substrate utilisation by the soil microbial community in a ‘Cripps Pink’/M7 apple orchard – Andre H Meyer – South African Journal of Plant and Soil

* The Soil Biota Composition along a Progressive Succession of Secondary Vegetation in a Karst Area – Jie Zhao – PLOS ONE

Effects of salinization and crude oil contamination on soil bacterial community structure in the Yellow River Delta region, China – Yong-chao Gao – Applied Soil Ecology

Water microbiome

Community dynamics of prokaryotic and eukaryotic microbes in an estuary reservoir – Zhen Sun – Scientific Reports

Microbial diversity and community structure across environmental gradients in Bransfield Strait, Western Antarctic Peninsula – Camila N. Signori – Frontiers in Microbiology

Metagenomics

Assessment of quality control approaches for metagenomic data analysis – Qian Zhou – Scientific Reports

PaperClip: rapid multi-part DNA assembly from existing libraries – Maryia Trubitsyna – Nucleic Acids Research

Microbial phylogeny

* Assessing the global phylum level diversity within the bacterial domain: A review – Noha H. Youssef – Journal of Advanced Research

Science, publishing, career

Crosspost: Using Google Scholar in Scholarly Workflows – Jonathan Eisen – microBEnet

Hilarious: Overly honest references: “Should we cite the crappy Gabor paper here?” – RetractionWatch – (Note: paper has been removed – see a screenshot here)

Microbes in the news

* Bacteria Hysteria? Deadly bacteria normally found in toilets was discovered in the microwave of these students – The Journal.ie

Bik’s Picks

Comparative analysis of the domestic cat genome reveals genetic signatures underlying feline biology and domestication – Michael J. Montague – PNAS USA

UCSF develops site to make sense out of sugar science – Erin Allday – SFGate

Found: The Ideal Fatness for Elephant Seals – Elizabeth Preston – Discover

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Microbiome digest, November 5, 2014

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Bioinformatic tools for tree building and metagenomics, microbiome of iPads in hospitals, and stool samples from indigenous cultures.
Human clinical microbiome

MetaGeniE: Characterizing Human Clinical Samples Using Deep Metagenomic Sequencing – Arun Rawat – PLOS ONE

“We have developed an efficient strategy that identifies “all against all” relationships between sequencing reads and reference genomes.”

Human gut microbiome

Human Fecal Microbiome–Based Biomarkers for Colorectal Cancer – Vilvapathy Narayanan – Cancer Prevention Research

“A recent study by Zackular and colleagues… provides an important way forward here in showing that specific analysis of multiple aspects of the microbiome composition in toto provides reliable detection of both precancerous and cancerous lesions. “

Plant microbiome

Covalently linked hopanoid-lipid A improves outer-membrane resistance of a Bradyrhizobium symbiont of legumes – Alba Silipo – Nature Communications

“Here we demonstrate that a photosynthetic Bradyrhizobium strain, symbiont of Aeschynomene legumes, synthesizes a unique LPS bearing a hopanoid covalently attached to lipid A.”

Microbiome of the built environment

* Surface Microbiology of the iPad Tablet Computer and the Potential to Serve as a Fomite in Both Inpatient Practice Settings as Well as Outside of the Hospital Environment – Elizabeth B. Hirsch – PLOS ONE

“Thirty iPads belonging to faculty with a variety of practice settings were sampled to determine the presence and quantity of clinically-relevant organisms.”

Bioinformatic tools

A Phylogeny-Based Benchmarking Test for Orthology Inference Reveals the Limitations of Function-Based Validation – Kalliopi Trachana – PLOS ONE

“Therefore, we constructed high quality “gold standard” orthologous groups that can serve as a benchmark set for orthology inference in bacterial species.”

Towards more accurate ancestral protein genotype–phenotype reconstructions with the use of species tree-aware gene trees – Mathieu Groussin – Molecular Biology and Evolution

“Here, we show with simulations that utilizing information on species history using a model that accounts for the duplication, horizontal transfer and loss (DTL) of genes statistically increases ASR accuracy.”

IQ-TREE: A fast and effective stochastic algorithm for estimating maximum likelihood phylogenies – Lam-Tung Nguyen – Molecular Biology and Evolution

“We show that a combination of hill-climbing approaches and a stochastic perturbation method can be time-efficiently implemented.”

Sampling and DNA extraction techniques

Nasal Screening for MRSA: Different Swabs – Different Results! – Philipp Warnke – PLOS ONE

“This study investigates the performance of different swab-types in nasal MRSA-screening by utilizing a unique artificial nose model to provide realistic and standardized screening conditions.”

Microbes in the news

Les Dethlefsen from our lab did an excellent “AMA” (ask me anything) on Reddit/Science today, on the human gut microbiota. Read the questions and Les’ answers here.

* Fecal Matters: A Stepping Stool to Understanding Indigenous Cultures – Daniella Lowenberg – PLOS Blogs

“Suspecting that this excrement is rich in biological clues, a group of researchers conducted experiments to investigate fecal microbiomes and published a study in PLOS ONE detailing insights into the diets and lifestyles of two ancient indigenous cultures of Puerto Rico”

Quantifying the Microbiome and the State of Crowd Science with Jessica Richman (1h Podcast) – The Quantified Body

“…we have an excellent guest today to bring us up to date on all this. Jessica Richman, is CEO and co-founder of uBiome.”

* If you think your city subway only consists of smelly disgruntled commuters, think again… – Marcus Leung – MicroBEnet

“Have you ever wondered what microbes are around you when you take public transport? Personally, I think about it every day during my two-hour subway commute to and from our lab here in Hong Kong.”

Science, publishing, and career

Metascience could rescue the ‘replication crisis’ – Jonathan W. Schooler – Nature

“Metascience, the science of science, uses rigorous methods to examine how scientific practices influence the validity of scientific conclusions. “

Interactive notebooks: Sharing the code – Helen Shen – Nature

“The free IPython notebook makes data analysis easier to record, understand and reproduce.”

Column: It takes time and a team to win grants – Ingrid Eisenstadter – Nature

“All our applicants are people who were bright enough to get PhDs and MDs, but the proposals we receive tend to share the same flaws, whether they come from recent graduates or from researchers with years of experience.”

Elsevier bad for your h-index? – Ferniglab

“The negotiations between the Dutch universities and Elsevier have foundered…., which means that from 1 January 2015, Dutch researchers will no longer have access to Elsevier journals.”

Sexy molecules! Comedian Megan Amram talks ‘Science… for Her!’ (Q&A) – Amanda Kooser -CNET

“”Parks and Recreation” writer Megan Amram offers up a “raunchy, crazy” textbook full of carbon dating, physics as nail art and kale.”

Bik’s Picks

YouTube video: Brian Cox visits the world’s biggest vacuum chamber – Human Universe: Episode 4 Preview – BBC Two

“…what happens when a bowling ball and a feather are dropped together under the conditions of outer space (vacuum – EB).”

Study in paradise: Stanford professors turn Hawaii into a living science classroom – Bjorn Carey – Stanford News

“Students in the School of Earth Science’s Wrigley Field Program in Hawaii spend the quarter measuring vegetation, coral reefs and volcanoes to understand the dynamics of one of the planet’s most interesting ecosystems.”

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General microbiology and science digest, October 27, 2014

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A new Shiny R tool for microbial communities, virus-like pictures in human distal gut, interaction between oral bacteria, dancing your PhD, and X-ray movies of human joints in action.

Bioinformatics

* Seed: a user-friendly tool for exploring and visualizing microbial community data –
Daniel Beck – Bioinformatics

“Seed is written in R using the Shiny library. This provides access to powerful R based functions and libraries through a simple user interface. “

Viruses and phages

With cool pictures: Characterization of virus-like particles associated with the human faecal and caecal microbiota – Lesley Hoyles – Research in Microbiology

“Various methodologies for the recovery of VLPs from faeces were tested and optimized, including successful down-stream processing of such samples for the purpose of an in-depth electron microscopic analysis, pulsed-field gel electrophoresis and efficient DNA recovery.”

Transcriptomics / Proteomics / Metabolomics

Thermophilic microbial cellulose decomposition and methanogenesis pathways recharacterized by metatranscriptomic and metagenomic analysis – Yu Xia – Scientific Reports

“The metatranscriptomic recharacterization in the present study captured microbial enzymes at the unprecedented scale of 40,000 active genes belonged to 2,269 KEGG functions were identified.”

Proteomic and transcriptional analysis of interaction between oral microbiota Porphyromonas gingivalis and Streptococcus oralis – Kazuhiko Maeda – Journal of Proteome Research

“Here, using shotgun proteomics we examined the molecular basis of mixed-biofilm formation by P. gingivalis with Streptococcus oralis.”

Review: Toward the comprehensive understanding of the gut ecosystem via metabolomics-based integrated omics approach – Wanping Aw, Shinji Fukuda – Seminars in Immunopathology

“In this review, we discuss in detail the relationship between gut microbiota and its metabolites … in the host health and etiopathogenesis of various pathological states such as multiple sclerosis, autism, obesity, diabetes, and chronic kidney disease. “

More Microbiology

Biofilms: Five-Star Accommodations for the Aerobically Challenged – Robert A. Cramer – Current Biology

“A recent study finds that fungal biofilms are capable of supporting growth of anaerobic bacteria, suggesting that these fungi can promote bacterial growth in otherwise toxic environments.”

Microbes in the news

* Sorry, Your Gut Bacteria Are Not the Answer to All Your Health Problems – Gabrielle Canon – Mother Jones

“We’re told that tweaks to the microbiome can cure everything from allergies to Ebola. Not exactly, say experts. …despite the optimism, some researchers caution that much of what we hear about microbiome science isn’t always, well, science. “

* Orthopedic surgeon studies bear bacteria to aid bear attack victims – Healio

“Working with the Montana Fish, Wildlife & Parks, Iwersen has been collecting cultures of bacteria from the mouths of grizzly bears and correlating them with the types of bacteria found in the bear bites on patients. “

Mexican scientist investigates intestinal bacteria – BetaWired

“Recent findings of the investigator Xicotencatl Gracida Canales…at Harvard University in Cambridge, USA, suggest that in the absence of an intestinal shield, variations in bacterial metabolism can affect reproductive cells and cause infertility in an animal model called C. Elegans.”

Algae-Based Material Takes On Body Odor – Dana Dovey – NewsWeek

“A team of Swedish researchers from the KTH Royal Institute of Technology has found a way to eliminate the growth of this smell-inducing bacteria using one of nature’s best antimicrobials, algae.”

MoBE Postdoctoral Fellowship: From Source to Tap: Linking the Drinking Water Microbiome to Human Health – Sarah Haig – MicroBEnet

“We hypothesize that the microbial communities in municipally treated drinking water are a source of opportunistic pathogens, posing a risk to people with cystic fibrosis”

Science, publishing, career

Is NIH policy the best way to sex equality in studies? – Bethany Brookshire – Science News

“The end goal will be to make sure that NIH-funded scientists “balance male and female cells and animals in preclinical studies in all future [grant] applications” to the NIH.”

Some suggestions for having diverse speakers at meetings – Jonathan Eisen – The Tree of Life

“Some people were asking what one can do to improve gender diversity at meetings so I thought I would post this which I was meaning to do anyway “

‘Dance Your Ph.D.’ finalists announced – John Bohannon – Science

“Rather than reading a paper about it, why not watch a dance? A ballet and a modern dance on those very topics have made it into the finals of this year’s “Dance Your Ph.D.” contest.”

Bik’s Picks

Interactive world map of vaccine-preventable outbreaks – Council for Foreign Relations

“This interactive map visually plots global outbreaks of measles, mumps, whooping cough, polio, rubella, and other diseases that are easily preventable by inexpensive and effective vaccines.”

Dietary cocoa flavanols reverse age-related memory decline in mice – Science Daily

“Dietary cocoa flavanols —- naturally occurring bioactives found in cocoa —- reversed age-related memory decline in healthy older adults, according to a new study. Flavanols are also found naturally in tea leaves and in certain fruits and vegetables”

Amazing X-ray GIFs Show Joints In Motion – Lisa Winter – IFL Science

“Cameron Drake of San Francisco has created a collection of magnificent images showing joints in motion. He was aided by orthopedic physician Dr. Noah Weiss and the finished product is completely amazing. “

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Microbiome Digest, October 23, 2014

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Not much microbiome news today – which was good because I got time to watch the solar eclipse and a huge solar storm at the same time.  Enjoy the read!

Animal models of microbiome research

Lyn Deficiency Leads to Increased Microbiota-Dependent Intestinal Inflammation and Susceptibility to Enteric Pathogens – Morgan E. Roberts – Journal of Immunology

“Lyn2/2 mice exhibited profound cecal inflammation, bacterial dissemination, and morbidity following S. Typhimurium challenge and greater colonic inflammation throughout the course of C. rodentium infection.”

Rock microbiome

* Halophilic Archaea Cultivated from Surface Sterilized Middle-Late Eocene Rock Salt Are Polyploid – Salla T. Jaakkola – PLOS ONE

“We used real-time PCR to show that our isolates are polyploid, with genome copy numbers of 11–14 genomes per cell in exponential growth phase.”

More Microbiology

Zooming in to see the bigger picture: Microfluidic and nanofabrication tools to study bacteria – Felix J. H. Hol, Cees Dekker – Science

“Here, we review the new scientific insights gained by using a diverse set of nanofabrication and microfluidic techniques to study individual bacteria and multispecies communities.”

Review: Theory and Empiricism in Virulence Evolution – James J. Bull, Adam S. Lauring – PLOS Pathogens

“Our purpose here is to offer a brief introduction to virulence theory, explain some of its strengths and weaknesses, and suggest how theory might be united with empiric data”

Techniques

Comparing the new 16S rRNA V4 and ITS primers to the old primers-RESULTS! – Embriette Hyde – MicroBEnet

“The Knight lab has been working hard testing new primers for 16S rRNA amplicon production and its time to share our progress.”

Microbes in the News

As permafrost soils thaw, soil microbes amplify global climate change – Science Daily

“Now, research by an international team of scientists from the U.S., Sweden and Australia, led by University of Arizona scientists, shows that a single species of microbe, discovered only very recently, is an unexpected key player in climate change.”

* The Scientist: Prof. Esther Angert Studies Extreme Bacteria – Siddesh Ramesh – Cornell Sun

“While the majority of bacteria cannot be seen without a microscope, there exists a group of bacterial species that is visible to the naked eye. Known as Epulopiscium, they are “an extreme on the spectrum of diversity of bacterial life in existence,” according to Prof. Esther Angert, microbiology.”

Bik’s Picks

Flare Alert: Monster Sunspot Turns Toward Earth – Ian O’Neill – Discovery

“Amateur astronomers have been wowed by a vast sunspot that has rotated to face Earth, the largest since this solar cycle began in 2008, and solar observatories (on the ground and orbiting Earth) are closely monitoring the region.“

Watch cell division with new, remarkable resolution: Nobel winner Betzig strikes again – Tech Times

“Just weeks after sharing the Nobel Prize in chemistry for his work involving high-resolution microscopes, a U.S. researcher has again stunned the scientific world with a new technique that peers deeply into living cells.”

Ancient Europeans do not drink milk according to new study – BetaWired

“Almost everyone drinks milk today but a new study shows that ancient Europeans were not milk lovers back in the old days. According to a DNA analysis result, ancient Europeans are lactose intolerant.”

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Microbiome digest, October 21, 2014

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Human oral microbiome

Abstract 4834: Microbiome in Oral Epithelial Dysplasia and Squamous Cell Carcinoma
Deepak Saxena – Cancer Research

“PCR amplicons targeting V3-V5 region of 16S rRNA gene were sequenced by 454 pyrosequencing. “

Human respiratory microbiome

Microbial Communities in the Upper Respiratory Tract of Patients with Asthma and Chronic Obstructive Pulmonary Disease – HeeKuk Park – PLOS ONE

“To account for the qualitative and quantitative diversity of the 16S rRNA gene in the oropharynx, the microbiomes of 18 asthma patients, 17 COPD patients, and 12 normal individuals were assessed using a high-throughput next-generation sequencing analysis.”

Human gut microbiome

Decreased bacterial diversity characterizes an altered gut microbiota in psoriatic arthritis and resembles dysbiosis of inflammatory bowel disease – Jose U. Scher – Arthritis & Rheumatology

“High-throughput 16S rRNA pyrosequencing was utilized to compare community composition of gut microbiota in PsA patients, subjects with psoriasis of the skin and healthy, matched-controls. “

Pregnancy and birth

The Salivary Scavenger and Agglutinin in Early Life: Diverse Roles in Amniotic Fluid and in the Infant Intestine – Martin Parnov Reichhardt – Journal of Immunology

“The present study revealed that SALSA was present in the amniotic fluid (AF) and exceptionally enriched in both meconium and feces of infants. “

Animal microbiome

* Unique and shared responses of the gut microbiota to prolonged fasting: a comparative study across five classes of vertebrate hosts – Kevin D. Kohl – FEMS Microbiology Ecology

“We used 16S rRNA sequencing to document changes in colonic and cecal microbiomes of animals representing five classes of vertebrates at four time points through prolonged fasting: tilapia, toads, geckos, quail, and mice. “

GeoChip-based insights into the microbial functional gene repertoire of marine sponges (HMA, LMA) and seawater – Kristina Bayer – FEMS Microbiology Ecology

“By use of GeoChip, altogether 20,273 probes encoding for 627 functional genes and representing 16 gene categories were identified”

Natural volcanic CO2 seeps reveal future trajectories for host–microbial associations in corals and sponges – Kathleen M Morrow – ISME Journal

“The corals Acropora millepora and Porites cylindrica were less abundant and hosted significantly different microbial communities at the CO2 seep than at nearby control sites <500 m away.”
Plant microbiome

Phylogenetic conservatism in plant-soil feedback and its implications for plant abundance – Brian L. Anacke – Ecology Letters

“We conclude that soil biota influence the abundance of close plant relatives in nature.”

Bioreactor microbiome

Influence of Acidic pH on Hydrogen and Acetate Production by an Electrosynthetic Microbiome – Edward V. LaBelle – PLOS ONE

“Production of hydrogen and organic compounds by an electrosynthetic microbiome using electrodes and carbon dioxide as sole electron donor and carbon source, respectively, was examined after exposure to acidic pH (~5). “

Metagenomics / Transcriptomics / Bioinformatics

Census-based rapid and accurate metagenome taxonomic profiling – Amirhossein Shamsaddini – BMC Genomics

“We have developed a robust subsampling-based algorithm implemented in a tool called CensuScope meant to take a ‘sneak peak’ into the population distribution and estimate taxonomic composition as if a census was taken of the metagenomic landscape. “

Metatranscriptomes from diverse microbial communities: assessment of data reduction techniques for rigorous annotation – Andrew Toseland – BMC Genomics

“To investigate the effect of such techniques on the annotation of metatranscriptome data we assess two commonly employed methods: clustering and de-novo assembly. To do this, we also developed an approach to simulate 454 and Illumina metatranscriptome data sets with varying degrees of taxonomic diversity. “

Microbial Ecology

Mathematical Modeling of Microbial Community Dynamics: A Methodological Review – Hyun-Seob Song – Processes

“In this article, we provide an overview of mathematical tools that include not only current mainstream approaches, but also less traditional approaches that, in our opinion, can be potentially useful. “

A phylogenetic perspective on species diversity, β-diversity, and biogeography for the microbial world – Albert Barberán† and Emilio O. Casamayor – Molecular Ecology

“We explored links between evolution/phylogeny and community ecology using bacterial 16S rRNA gene information from a high altitude lakes district dataset to describe phylogenetic community composition, spatial distribution, and β-diversity and biogeographical patterns applying evolutionary relatedness without relying on any particular operational taxonomic unit definition.”

Distance-Decay and Taxa-Area Relationships for Bacteria, Archaea and Methanogenic Archaea in a Tropical Lake Sediment – Davi Pedroni Barreto – PLOS ONE

“The samples were analyzed using T-RFLP (Terminal restriction fragment length polymorphism) targeting mcrA (coding for a subunit of methyl-coenzyme M reductase) and the genes of Archaeal and Bacterial 16S rRNA.”

More microbiology

From Denise Monack’s lab: Role of disease-associated tolerance in infectious superspreaders – Smita Gopinath – PNAS USA

“Using a mouse model of Salmonella infection, we show that levels of Salmonella are equivalent between antibiotic-treated superspreader and nonsuperspreader hosts; however, superspreader hosts are uniquely able to tolerate antibiotic treatment, unlike nonsuperspreader hosts. “

*Also see:  Antibiotics may help Salmonella spread in infected animals, scientists learn – Stanford Medicine News

Spatial organization of bacterial chromosomes – Xindan Wang, David Z Rudner – Current Opinion in Microbiology

“Here, we summarize these different patterns highlighting similarities and differences and discuss the protein factors that help establish and maintain them.”

Bacterial healers: Microbes can redeem themselves to fight disease – Susan Gaidos – Science News

“It’s just a matter of time before bacterial-based treatments become a routine part of a doctor’s toolkit, says microbiologist Robert Britton of the Baylor College of Medicine in Houston, who is studying the relationship between microbes and human health. “

Techniques

Rapid fingerprinting of methanogenic communities by high-resolution melting analysis – Jaai Kim, Changsoo Lee – Bioresource Technology

“The new method produced robust community clustering and ordination results comparable to the results from the commonly used denaturing gradient gel electrophoresis (DGGE) performed in parallel.”

Microbes in the news

Our unique ‘microbial aura’ travels with us wherever we go – Science Friday – PRI

“Unless you lived exactly the same life as me, you would not have the same microbiome. You are, in essence, microbially unique,” explains Jack Gilbert

We’re making a Microbiome Documentary Series and could use your Help – Jamie – Reddit

“My name’s Jamie and I’m part of a team trying to crowdfund a documentary series on the human microbiome titled: ‘Redefining Human’.”

Building houses with bacteria – Euronews

“Houses of the future could be partially built with bacteria. It sounds like science fiction but researchers involved in an EU-backed project in Madrid are working towards making this a concrete reality.”

Bik’s Picks

The Role of Surface Chemistry in Adhesion and Wetting of Gecko Toe Pads – Ila Badge – Scientific Reports

“As expected, under wet conditions, adhesion on a hydrophilic surface (glass) was lower than that on a hydrophobic surface (alkyl-silane monolayer on glass).”

Scientists prepare for an 8-month mission to Mars – on Earth soil- BetaWired

“There’s a new experiment commencing in Hawaii, and the results will help NASA better prepare its astronauts for a lengthy mission to Mars.”

White rhino subspecies is down to one breeding male – Andrea James – BoingBoing

“Sad news from Kenya: the northern white rhino subspecies is down to one breeding male with the death of Suni this month. Only six remain.”

Scientists restore hearing in noise-deafened mice, pointing way to new therapies – ScienceDirect

“Scientists have restored the hearing of mice partly deafened by noise, using advanced tools to boost the production of a key protein in their ears.”

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General microbiology and science, October 14, 2014

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A living review of multivariate techniques, spatial organizations of bacterial genomes, and metabolomics of wetlands, pigs, marine bacteria and free-living humans.

Bioinformatics

* A Guide to Statistical Analysis in Microbial Ecology: a community-focused, living review of multivariate data analyses – Pier Luigi Buttigieg – FEMS Microbiology Ecology

“we present the GUide to STatistical Analysis in Microbial Ecology (GUSTA ME): a dynamic, web-based resource providing accessible descriptions of numerous multivariate techniques relevant to microbial ecologists”

Techniques

New approaches to understanding the spatial organization of bacterial genomes – Tung BK Le, Michael T Laub – Current Opinion in Microbiology

“Here, we review the current arsenal of techniques used to query chromosome structure”

Development of Clamping Probe for Rare DNA Detection using Universal Primers – Meyong il Kim – E-FAS Journal

“In this study, we evaluated the efficiency of rare gene detection for two kinds of clamping probes which were successfully utilized for eukaryotic symbiont analysis”

Metabolomics

Microbial community metabolic function in subsurface flow constructed wetlands of different designs – Mark Button – Ecological Engineering

“Microbial community function followed a clear gradient along the flow direction. Metabolic profiles were system specific (horizontal, vertical, and aerated).”

A high fat, high choleststerol diet leads to changes in metabolite patterns in pigs – a metabolomic study – Jianghao Sun – Food Chemistry

“Extracts of plasma, fecal and urine samples from pigs fed high fat or basal regular diets for 11 weeks were analyzed using ultra-high performance liquid chromatography with high-resolution mass spectrometry “

Free-living individuals – as in “not in prison”?
An NMR metabolomics approach reveals a combined-biomarkers model in a wine interventional trial with validation in free-living individuals of the PREDIMED study – Rosa Vázquez-Fresno – Metabolomics

A High-Resolution LC-MS-Based Secondary Metabolite Fingerprint Database of Marine Bacteria – Liang Lu – Nature Scientific Reports

“Till now, 1,430 bacterial strains spanning 168 known species collected from different marine environments were cultured and profiled. “

Viruses and phages

Ribonucleotide reductases reveal novel viral diversity and predict biological and ecological features of unknown marine viruses – Eric G. Sakowski – PNAS USA

“We identify ribonucleotide reductase (RNR) genes as superior markers of viral diversity. RNR genes are distributed over a broad range of viruses”

More microbiology

Strength in Diversity – Daniel J. Wolter, Lucas R. Hoffman – Cell Host & Microbe

“In this issue of Cell Host & Microbe, Hammer et al. (2014) show that distinct, slow-growing bacteria have better in vitro and in vivo growth and virulence when cocultured than in isolation. “

The Journal of Infectious Diseases has a special Issue on Polio: The Final Phase of Polio Eradication and Endgame Strategies for the Post-Eradication Era – Journal of Infectious Diseases

Science, publishing, career

Correcting the scientific record: An introduction to retractions – Bonnie Swoger – Scientific American

“Although the system is far from perfect, the retraction process is one of the ways in which the scientific literature corrects itself over time.”

 

Bik’s Picks

When Racism Was a Science – ‘Haunted Files: The Eugenics Record Office’ Recreates a Dark Time in a Laboratory’s Past – Joshua A. Krisch – New York Times

“In its heyday, the office was the premier scientific enterprise at Cold Spring Harbor. There, bigoted scientists applied rudimentary genetics to singling out supposedly superior races and degrading minorities. “

Paul Ryan: Science doesn’t get climate change – Jane C. Timm – MSNBC

“A full 97% of researchers taking a stance on climate change say it’s man-made, as do 97-98% of the most frequently-published climate scientists. But according to Wisconsin Rep. Paul Ryan, they’re all wrong.”

Get fish fry with a side of science at ‘Science of the Supper Club’ this Friday – Lindsay Christians – The Capital Times

“Science is everywhere, even at a Friday night fish fry. That’s the message of a new event this Friday called “Science of Supper Clubs,” part of the four-day Wisconsin Science Festival held at various venues around the state.”

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Microbiome digest, October 8, 2014

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Blogging from our yearly retreat in Santa Cruz, California: Rethinking Enterotypes, Wolbachia phylogenomics,  hydrothermal vents, and the influence of salamanders on soil microbiome.

Human Microbiome General

Genes & cells: Body microbes make useful molecules: Human microbiome produces thousands of drug candidates – Tina Hesman Saey – Science News

Human Gut Microbiome

Rethinking “Enterotypes” – Dan Knights – Cell Host and Microbe

“However, as discussed here, several different methods of collapsing enterotype variation into a few discrete clusters suggest that enterotype distribution is continuous and can vary widely within an individual.”

Fecal Bacterial Community Changes Associated with Isoflavone Metabolites in Postmenopausal Women after Soy Bar Consumption – Cindy H. Nakatsu – PLOS ONE

“Using DGGE profiles of PCR amplified 16S rRNA genes (V3 region) to compare microbial communities in fecal samples collected one week before and one week during soy supplementation revealed significant differences (ANOSIM p<0.03) before and after soy supplementation in all subjects. “

Insect microbiome

Phylogenomic analyses uncover origin and spread of the Wolbachia pandemic – Michael Gerth  – Nature Communications

“Here we present the first comprehensive phylogenomic analysis of Wolbachia supergroup relationships based on new whole-genome-shotgun data.”

Coral microbiome

Comparing Bacterial Community Composition of Healthy and Dark Spot-Affected Siderastrea siderea in Florida and the Caribbean – Christina A. Kellogg – PLOS ONE

“Microbial-community DNA was extracted from coral samples (mucus, tissue, and skeleton), amplified using bacterial-specific primers, and applied to PhyloChip G3 microarrays to examine the bacterial diversity associated with this coral. “

Soil Microbiome

Summer temperature increase has distinct effects on the ectomycorrhizal fungal communities of moist tussock and dry tundra in Arctic Alaska – Luis N. Morgado – Global Change Biology

“We used Ion Torrent sequencing of the rDNA internal transcribed spacer 2 (ITS2) region to compare ECM fungal communities in plots with and without long-term experimental warming in both dry and moist tussock tundra.”

A metagenomics-based approach to the top-down effect on the detritivore food web: a salamanders influence on fungal communities within a deciduous forest – Donald M. Walker – Ecology and Evolution

“From each sample, DNA was extracted, fungal-specific amplification performed, and 454 pyrosequencing was used to sequence the nuclear ribosomal internal transcribed spacer (ITS2) region and partial ribosomal large subunit (LSU).”

Water microbiome

Evolutionary Strategies of Viruses, Bacteria and Archaea in Hydrothermal Vent Ecosystems Revealed through Metagenomics – Rika E Anderson – PLOS ONE

“Here, we explore the evolutionary strategies of both microorganisms and viruses in hydrothermal systems through comparative analysis of a cellular and viral metagenome, “

Metabolomics

Discovery and Characterization of Gut Microbiota Decarboxylases that Can Produce the Neurotransmitter Tryptamine – Brianna B. Williams – -Cell Host and Microbe

“Using a combination of genetics, biochemistry, and crystallography, we identify and characterize two phylogenetically distinct enzymes found in the human microbiome that decarboxylate tryptophan to form the β-arylamine neurotransmitter

Techniques

Selective Microbial Genomic DNA Isolation Using Restriction Endonucleases – Helen E. Barnes – PLOS ONE

“Using synthetic genome mixtures, we demonstrate 80% recovery of Escherichia coli genomic DNA even when only femtogram quantities are spiked into 10 µg of human DNA background.”

 More Microbiology

Pseudomonas aeruginosa eradicates Staphylococcus aureus by manipulating the host immunity – Erwan Pernet – Nature Communications

“Our results indicate that a bacterium can eradicate another bacterium by manipulating the host immunity.”

Preparation and evaluation of low-calorie functional ice cream containing inulin, lactulose and Bifidobacterium lactis  – Majid Hashemi- International Journal of Dairy Technology

“This study was aimed to investigate the effects of replacing 5% fat and sugar by inulin and lactulose, respectively, on the survival of Bifidobacterium lactis and physicochemical and sensorial characteristics of the ice cream. “

Microbes in the News

Second Genome, Mayo Clinic team up to explore the microbiome – Stephanie M. Lee – SF Gate

“Second Genome will identify up to eight conditions in which the microbiome potentially plays a role, and the Mayo Clinic will provide human clinical samples for patients with those diseases.”

 Oral health affects overall health – PhillyTrib

“The evidence shows that an infection from periodontitis, or gum disease, can put you at risk for other serious conditions like heart disease, stroke and more.”

Safety Bees: Bacteria From Bees Used To Fight Infections – The Ledger

 “A group of 13 lactic-acid bacteria found in fresh honey from the honey stomach of bees could be the key to bringing an old folk remedy into modern science”

Bik’s Picks  

How dinosaurs divided their meals at the Jurassic dinner table – Science Daily

“How the largest animals to have ever walked on Earth fed, and how this allowed them to live alongside one another in prehistoric ecosystems, is the subject of new research.”

Imitation, Genetic Lineages, and Time Influenced the Morphological Evolution of the Violin – Daniel H. Chitwood – PLOS ONE

“Here, I provide an analysis of morphological evolution in the violin family, sampling the body shapes of over 9,000 instruments over 400 years of history.”

Cat Watch 2014: What’s it like being a cat? – BBC

“Cats are at a crucial point in their evolutionary journey as they transform from solitary hunters to domestic pets, a study by the BBC and the Royal Veterinary College has revealed.”
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General microbiology and science digest, October 2, 2014

Posted on by

Viruses and metagenomics, the soil of Central Park, and sweat eating bacteria.

Ecology

Loops and autonomy promote evolvability of ecosystem networks – Jianxi Luo – Scientific Reports

“To correlate ecosystem structure and evolvability, we adopt the NK model originally from evolutionary biology to generate and assess the ruggedness of fitness landscapes of a wide spectrum of model food webs with gradual variation in the amount of feeding loops and link density. “

Erosion of functional independence early in the evolution of a microbial mutualism
Kristina L. Hillesland – PNAS USA

“We show that as the bacterium Desulfovibrio vulgaris evolved for 1,000 generations in conditions forcing cooperation with the archaeon Methanococcus maripaludis, it lost a key metabolic trait that would be required for it to grow alone in most environments.”

Tree diversity does not always improve resistance of forest ecosystems to drought – Charlotte Grossiord – PNAS USA

“Within our study network of 160 forest stands across Europe, we found that mixed species forests are less exposed to drought stress in some regions only. “

Phages, viruses, and metagenomics

Dynamics of CRISPR Loci in Microevolutionary Process of Yersinia pestis Strains – Maria Paloma S. Barros – PLOS ONE

“This study allowed observing a microevolutionary process in a group of Y. pestis isolated from Brazil. “

Metagenomic approaches for direct and cell culture evaluation of the virological quality of wastewater – Tiong Gim Aw – Journal of Virological Methods

“In this study, NGS and bioinformatics have been employed for the direct detection and characterization of viruses in wastewater and of viruses isolated after cell culture. “

Metagenomics / Bioinformatics

Analysis of the Relationship between Genomic GC Content and Patterns of Base Usage, Codon Usage and Amino Acid Usage in Prokaryotes: Similar GC Content Adopts Similar Compositional Frequencies Regardless of the Phylogenetic Lineages – Hui-Qi Zhou – PLOS ONE

“The GC contents of 2670 prokaryotic genomes that belong to diverse phylogenetic lineages were analyzed in this paper. “

Benchmarking Undedicated Cloud Computing Providers for Analysis of Genomic Datasets
Seyhan Yazar – PLOS ONE

“We benchmarked two established cloud computing services, Amazon Web Services Elastic MapReduce (EMR) on Amazon EC2 instances and Google Compute Engine (GCE), using publicly available genomic datasets”

SDT: A Virus Classification Tool Based on Pairwise Sequence Alignment and Identity Calculation – Brejnev Muhizi Muhire – PLOS ONE

“Here we present Sequence Demarcation Tool (SDT), …that aims to provide a robust and highly reproducible means of objectively using pairwise genetic identity calculations to classify any set of nucleotide or amino acid sequences.”

A two-stage statistical procedure for feature selection and comparison in functional analysis of metagenomes – Naruekamol Pookhao – Bioinformatics

“We propose a two-stage statistical procedure for selecting informative features and identifying differentially abundant features between two or more groups of microbial communities.”

FOAM (Functional Ontology Assignments for Metagenomes): a Hidden Markov Model (HMM) database with environmental focus – Emmanuel Prestat – Nucleic Acids Research

“A new functional gene database, FOAM (Functional Ontology Assignments for Metagenomes), was developed to screen environmental metagenomic sequence datasets. “

Microbes in the News

Soil Microbiome of Central Park – Jef Akst – The Scientist

“The soil of New York City’s Central Park is bursting with biodiversity spanning all three domains of life, according to a study published today”

Supporting the “Good” Gut Microbes – Anna Azvolinksy – The Scientist

“During systemic infection, mice kick-start the production of a specific sugar to feed and protect the beneficial bacteria in their guts while fighting pathogenic strains.”

Sweat-Eating Bacteria: Acne Miracle Cure? – Discovery News

“A new, small study has shown that applying a topical creme containing the bacteria leads to healthier skin and could be used to treat acne and promote healing in wounds.”

Women in Science

* Sexism in Science – sbhatnagar3 – Phylogenomics Blogspot

“Please don’t treat these seminars as a fashion show. It distracts the people away from your work”.”

Bik’s Picks

Behavior of bats at wind turbines – Paul. M. Cryan – PNAS USA

“Bats are dying in unprecedented numbers at wind turbines, but causes of their susceptibility are unknown. “

Flexible energetics of cheetah hunting strategies provide resistance against kleptoparasitism – David M. Scantlebury – Science

“We show that daily energy expenditure (DEE) of cheetahs was similar to size-based predictions and positively related to distance traveled.”

Previously unseen details of seafloor exposed in new map – Science Daily

“Twice as accurate as the previous version, the new map features a much more vivid picture of seafloor structures, including thousands of previously uncharted mountains.”

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General microbiology and science, September 29, 2014

Posted on by

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 Molecular Microbiology, 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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