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Biology subjects

Sosinski, L. M.

Publications and source records attributed to Sosinski, L. M..

2 recordsLinked to original sources

MolEvolvR: a web-app for characterizing proteins using molecular evolution and phylogeny

Studying proteins through the lens of evolution can reveal features such as conserved domains, lineage-specific variants, and co-occurring domain architectures in phylogenetic context across all superkingdoms. MolEvolvR enables researchers to conduct such evolution-focused studies to generate testable hypotheses about protein function and evolution. MolEvolvR is a novel web-app allowing researchers to visualize the molecular evolution of their proteins of interest in a phylogenetic context across the tree of life. It accepts multiple input formats - protein/domain sequences, homologous proteins, or domain scans - and, using a general-purpose computational workflow, returns detailed homolog data and dynamic graphical summaries (e.g., phylogenetic trees, multiple sequence alignments, domain architectures, domain proximity networks, phyletic spreads, co-occurrence patterns across lineages). MolEvolvR performs domain-centric searches to capture remote homologs that are missed by full-length searches, integrates domain architecture evolution with phyletic distribution analyses, and provides evolutionary context visualizations that reveal lineage-specific adaptations versus those that are broadly conserved. Thus, MolEvolvR is a powerful, easy-to-use web interface for computational protein characterization. The web-app can be accessed here: https://jravilab.org/molevolvr.

genomics↗

The glutathione import system satisfies the Staphylococcus aureus nutrient sulfur requirement and promotes interspecies competition.

Sulfur is an indispensable element for proliferation of bacterial pathogens. Prior studies indicated that the human pathogen, Staphylococcus aureus utilizes glutathione (GSH) as a source of nutrient sulfur; however, mechanisms of GSH acquisition are not defined. Here, we identify a previously uncharacterized five-gene locus comprising a putative ABC-transporter and {gamma}-glutamyl transpeptidase (ggt) that promotes S. aureus proliferation in medium supplemented with either reduced or oxidized GSH (GSSG) as the sole source of nutrient sulfur. Based on these phenotypes, we name this transporter the Glutathione import system (GisABCD). We confirm that Ggt is capable of cleaving GSH and GSSG {gamma}-bonds and that this process is required for their use as nutrient sulfur sources. Additionally, we find that the enzyme is cell associated. Bioinformatic analyses reveal that only Staphylococcus species closely related to S. aureus encode GisABCD-Ggt homologues. Homologues are not detected in Staphylococcus epidermidis. Consequently, we establish that GisABCD-Ggt provides a competitive advantage for S. aureus over S. epidermidis in a GSH-dependent manner. Overall, this study describes the discovery of a nutrient sulfur acquisition system in S. aureus that targets GSH and promotes competition against other staphylococci commonly associated with the human microbiota.

microbiology↗