host/pathogen

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 …

Phage defence by deaminase-mediated depletion of deoxynucleotides in bacteria

DciA Helicase Operators Exhibit Diversity across Bacterial Phyla

Despite the fundamental importance of DNA replication for life, this process remains understudied in bacteria outside Escherichia coli and Bacillus subtilis. In particular, most bacteria do not encode the helicase-loading proteins that are essential in E. coli and B. subtilis for DNA replication. Instead, most bacteria encode a DciA homolog that likely constitutes the predominant mechanism of helicase operation in bacteria. However, it is still unknown how DciA structure and function compare across diverse phyla that encode DciA proteins. In this study, we performed computational evolutionary analyses to uncover tremendous diversity among DciA homologs. These studies provide a significant advance in our understanding of an essential component of the bacterial DNA replication machinery.

Novel Internalin P homologs in Listeria ivanovii londoniensis and Listeria seeligeri

The intracellular bacterial pathogen Listeria monocytogenes can breach protective barriers in the pregnant host, allowing the colonization of the placenta in pregnant people and resulting in numerous adverse pregnancy outcomes. Previous studies aimed at delineating the mechanisms behind placental colonization of L. monocytogenes identified a key virulence factor, internalin P (InlP). The internalin family of proteins has been studied extensively due to their conservation in the genus Listeria and their contribution to virulence and pathogenicity in L. monocytogenes. Still, many questions remain regarding the evolution of internalins and their potential roles in non-pathogenic Listeria. Our work addresses this gap in knowledge by (1) identifying additional InlP homologs in Listeria, including L. ivanovii, L. seeligeri, L. innocua, and L. costaricensis, and (2) characterizing these homologs using computational evolutionary methods to compare their primary sequences, domain architectures, and structural models. Together, our findings contribute to the field by providing insights into the evolution of one key member of the internalin family, as well as serving as a catalyst for future studies of InlP and its role in Listeria pathogenesis.

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

Studying proteins through the lens of evolution can help identify conserved features and lineage-specific variants, and potentially, their functions. MolEvolvR (http://jravilab.org/molevolvr) is a web-app that enables researchers to run a …

Discovery of a predominant and distinct lineage of Mycobacterium tuberculosis in Brazilian indigenous population

After nearly a century of vaccination and six decades of drug therapy, tuberculosis (TB) kills more people annually than any other infectious disease. Substantial challenges to disease eradication remain among vulnerable and underserved populations. …

sRNA discovery

Discovering unique pathogenic sRNA in infected hosts

Phage-shock-protein (Psp) Envelope Stress Response: Evolutionary History & Discovery of Novel Players

The Staphylococcus aureus cystine transporters, TcyABC and TcyP, facilitate nutrient sulfur acquisition during infection

Variations on a theme: evolution of the phage-shock-protein system in Actinobacteria