The microbial communities that recolonize the skin after a slight abrasion more closely resemble the microbiomes of lower skin layers than those initially found on the skin's surface, according to a Genome Biology study by a team based in The Netherlands. Researchers from Radboud University, NIZO Food Research, and Wageningen University used 16S ribosomal RNA sequencing to look at the microbial community dynamics in skin layers over time, following a mild skin injury, in five individuals. After using a tape stripping method to remove the top layers of skin in an upper buttock area, researchers report seeing some skin microbiome variation related to host gender and immune response profiles. Even so, their results suggest that recolonization of the skin's surface relies on microbes from the deep skin layers — sites suspected of harboring each individual's "host indigenous microbiome."
University of Oxford researchers take a crack at unraveling the regulatory role of some messenger RNAs by focusing on a group of pseudogenes that lost their protein-coding capability in the rodent lineage. By assessing four dozen such loci, the study's authors say, they aimed to uncover mRNAs that have conserved post-transcriptional roles related to the regulation of other, related transcripts via interactions with microRNAs. Indeed, based on their results so far, the researchers argue that "post-transcriptional regulation by bifunctional mRNAs can persist over long evolutionary time periods even after their protein-coding ability has been lost."
An international team led by investigators in the UK has sifted through data for hundreds of Streptococcus pneumoniae isolates collected over the course of seven decades as part of an effort to understand the roots of penicillin resistance in pneumococcus, a bacterial strain known for its role in ear or sinus infections, pneumonia, and meningitis. From data on 426 pneumococcus isolates, researchers traced penicillin resistance back to an Australian pneumococci isolate — now believed to be the ancestor of a widespread, multidrug resistant pneumococcus clone known as PMEN1. Moreover, their results suggest that PMEN1 has been "uniquely promiscuous with its DNA, donating penicillin-resistance genes and sometimes many other genes associated with antibiotic resistance, virulence and cell adherence, to many genotypically diverse pneumococci."