Population gene introgression and high genome plasticity for the zoonotic pathogen Streptococcus agalactiae

The influence that bacterial adaptation (or niche partitioning) within species has on gene spillover and transmission among bacteria populations occupying different niches is not well understood. Streptococcus agalactiae is an important bacterial pathogen that has a taxonomically diverse host range making it an excellent model system to study these processes. Here we analyze a global set of 901 genome sequences from nine diverse host species to advance our understanding of these processes. Bayesian clustering analysis delineated twelve major populations that closely aligned with niches. Comparative genomics revealed extensive gene gain/loss among populations and a large pan-genome of 9,527 genes, which remained open and was strongly partitioned among niches. As a result, the biochemical characteristics of eleven populations were highly distinctive (significantly enriched). Positive selection was detected and biochemical characteristics of the dispensable genes under selection were enriched in ten populations. Despite the strong gene partitioning, phylogenomics detected gene spillover. In particular, tetracycline resistance (which likely evolved in the human-associated population) from humans to bovine, canines, seals, and fish, demonstrating how a gene selected in one host can ultimately be transmitted into another, and biased transmission from humans to bovines was confirmed with a Bayesian migration analysis. Our findings show high bacterial genome plasticity acting in balance with selection pressure from distinct functional requirements of niches that is associated with an extensive and highly partitioned dispensable genome, likely facilitating continued and expansive adaptation

Best Practices for Queer Metadata

This document is the result of two years of work by a group of nearly one hundred knowledge organisers, cataloguers, librarians, archivists, scholars, and information professionals with a concerted interest in improving the metadata treatment of queer people, communities, and items in GLAMS (Galleries, Libraries, Archives, Museums, and Special Collections) and other informational institutions. Their work has been supported by over 800 peer reviewers; combined, these groups make up the Queer Metadata Collective (QMDC). The QMDC builds upon earlier work done by the Trans Metadata Collective (TMDC), a similarly-organised group of metadata workers and information professionals with a concerted interest in improving the metadata representation of trans and gender-diverse people. The work of the TMDC culminated in Metadata Best Practices for Trans and Gender Diverse Resources, focusing on the description, cataloguing, and classification of information resources as well as the creation of metadata about trans and gender-diverse people, including authors, communities, and other creators. Following the publication of the Best Practices, several TMDC members founded and developed the QMDC over the summer of 2022. This document focuses on metadata by and about queer people, communities, and resources. While there is significant overlap between queer metadata and trans and gender diverse metadata, QMDC’s recommendations should not be seen as excluding or superseding TMDC’s, as trans and gender diverse people, communities, and resources have specific needs. For best practices and recommendations about trans and gender-diverse resources, please consult the TMDC document. If the TMDC and QMDC recommendations conflict (we are not aware of any instances in which they do), prefer the TMDC document for trans and gender diverse resources and the QMDC for other types of queer resources.UT Librarie