A team from the University of California, San Francisco, Stanford University, and elsewhere tallies up essential genes in the bacterial species Bacillus subtilis using a CRISPR/Cas9 interference strategy. After establishing a knockdown library targeting nearly 300 genes that are known or suspected of being essential in the bug, the researchers used CRISPR-based interference to verify essential genes, uncover potential drug targets, and gauge gene interactions and functions. "Our results provide a framework for systematic investigation of essential gene functions in vivo broadly applicable to diverse microorganisms and amenable to comparative analysis," they write.
Researchers with the National Institutes of Health and Boston University report on efforts to track human skin microbiome stability — and factors influencing it — over long periods of time in a dozen healthy individuals. Using metagenomic sequencing on samples from 17 skin sites per person collected at three time point over a couple months or a couple years, the team found that the composition of the bacterial, viral, and fungal communities were quite stable, though some body sites such as the foot varied more than others. Skin microbiome stability also appeared to vary somewhat between individuals and in relation to the phylogeny of microbes found at the skin sites sampled.
Finally, a Massachusetts Institute of Technology-, Harvard Medical School-, and Broad Institute-led team describes an isothermal RNA amplification pipeline approach for detecting the Zika virus' RNA genome in the field. The test is designed to be rapid and cell-free, sensing virus that's been extracted and amplified using nucleic acid sequence-based amplification by applying it to freeze-dried paper sensors. Along with this point-of-care test for the virus, the researchers came up with a CRISPR/Cas9-based method for distinguishing Zika virus genotypes. GenomeWeb more on the study, here.