In PLOS One, researchers from Malaysia and the UK introduce a resource for collecting and analyzing genomic information related to Streptococcus mitis, one of more than a dozen streptococci species that can colonize the human oral cavity, sometimes leading to complications such as bacterial infective endocarditis or septicemia. The database, known as StreptoBase, currently contains genome sequence data for more than 100 S. mitis strains, including 27 that were newly sequenced for the study. It is also home to bioinformatics tools for profiling pathogenicity and comparing genomic patterns across strains or related species, the study's authors explain, noting that "users may obtain insights into the biology, phylogeny, genetic variation, and virulence of particular strains or species of interest."
Nanjing Agricultural University researchers outline findings from a study focused on the gut transcriptome and microbiome of the cockroach species Periplaneta americana for another PLOS One paper. The team did RNA sequencing and 16S ribosomal RNA sequencing on midgut samples from cockroaches that had or had not been treated with the insecticide cycloxaprid, to get a glimpse at the pest's gene expression patterns and gut microbial community members, respectively. The analysis detected more than 82,900 expressed genes, including several dozen components of pathways related to digestion, detoxification, and stress response, the investigators note. Likewise, their microbiome analyses pointed to the presence of bugs that may assist with digestion and detoxification.
Finally, a team from Israel and Germany describes a genetic variant in the promoter region of the ST18 tumor suppressor gene that seems to significantly bump up the risk of developing pemphigus vulgaris, a serious and sometimes deadly autoimmune condition characterized by blistering on the skin and mucocutaneous tissues. As they report in PLOS Genetics, the researchers used deep, targeted sequencing to follow up on a chromosome 8 locus implicated in a prior genome-wide association study of the condition. Targeted sequence data from 16 pemphigus vulgaris patients of Jewish ancestry turned up a pemphigus vulgaris-associated variant in the ST18 promoter that appeared to enhance the gene's expression, potentially fueling skin inflammation and other features of the disease.