<i>In situ</i> NMR reveals a pH sensor motif in an outer membrane protein that drives bacterial vesicle production.

ABSTRACT: The outer membrane vesicles (OMVs) produced by diderm bacteria have important roles in cell envelope homeostasis, secretion, interbacterial communication, and pathogenesis. The facultative intracellular pathogen Salmonella enterica Typhimurium (STm) activates OMV biogenesis inside the acidic vacuoles of host cells by upregulating the expression of the outer membrane (OM) protein PagC, one of the most robustly activated genes in a host environment. Here, we used solid-state nuclear magnetic resonance (NMR) and electron microscopy (EM), with native bacterial OMVs, to demonstrate that three histidines, essential for the OMV biogenic function of PagC, constitute a key pH-sensing motif. The NMR spectra of PagC in OMVs show that they become protonated around pH 6, and His protonation is a

SUBMITTER: Wood NA 

PROVIDER: S-EPMC11785132 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature