STK-mediated FadR phosphorylation regulates the acid resistance and virulence of Streptococcus suis.

ABSTRACT: The phagolysosomes of macrophages play a crucial role in eradicating pathogenic microorganisms, but bacteria have evolved sophisticated mechanisms to survive in the acidic environment of phagolysosomes, leading to host infection and subsequent dissemination. However, it is largely unknown how bacteria sense the extracellular stimuli and regulate their acid tolerance capacity to resist the killing by host immune cells. Here, we report the new substrate FadR of the serine/threonine kinase (STK) in Streptococcus suis serotype 2 (SS2) and demonstrate that the phosphorylation site is Thr230. Notably, FadR phosphorylation significantly enhances the acid resistance of SS2, leading to an increase in the lethality of SS2 in mice, and a marked increase in bacterial load in the blood and various orga

SUBMITTER: Li S 

PROVIDER: S-EPMC12463286 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature