MCDB seminar will be from Jada George from the Cahoon lab will be presenting their research titled:
Title: Listeria monocytogenes post-translocation chaperones PrsA1 and PrsA2 are required for protein secretion and stress resistance.
Friday, February 14, 2025
A219B Langley Hall
12:00 PM
PrsA1 and PrsA2 are parvulin peptidyl-prolyl isomerases that function as post-translocation secretion chaperones in Listeria monocytogenes. To assess the contributions of PrsA1 and PrsA2 to L. monocytogenes protein secretion, we analyzed prsA1 and prsA2 deletion mutants and PrsA2 structural variants for altered secretion profiles when compared to wildtype bacteria using Tandem Mass-Tagged Mass Spectrometry (TMT-MS). We find that among the subset of known secreted proteins that demonstrate significantly altered secretion abundance, were those with characterized functions in virulence, cell division and cell wall assembly, and stress response. Further, to identify common pathways and protein factors that are altered when PrsA is absent, we conducted a meta-analysis comparing our data from L. monocytogenes to recently published quantitative proteomic secretome data of prsA deletion mutants from diverse Gram-positive human pathogens, including Streptococcus pneumoniae, Streptococcus pyogenes, and Staphylococcus aureus. We find that when PrsA homologs are absent in diverse Gram-positive bacteria, several pathways are similarly affected including those promoting bacterial virulence, cell division and cell wall assembly, and oxidative stress resistance. Moreover, we provide evidence of novel roles for L. monocytogenes PrsA1 and PrsA2 in oxidative stress resistance and cell morphology, and PrsA2 in thermo-osmotic stress resistance. Overall, this work suggests that Gram-positive PrsA homologs serve in the maturation of multiple protein substrates with varied and diverse functions.