CobB-mediated deacetylation of the chaperone CesA regulates Escherichia coli O157:H7 virulence

ABSTRACT

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a common food-borne pathogen that can cause acute diseases. Lysine acetylation is a post-translational modification (PTM) that occurs in various prokaryotes and is regulated by CobB, the only deacetylase found in bacteria. Here, we demonstrated that CobB plays an important role in the virulence of EHEC O157:H7 and that deletion of cobB significantly decreased the intestinal colonization ability of bacteria. Using acetylation proteomic studies, we systematically identified several proteins that could be regulated by CobB in EHEC O157:H7. Among these CobB substrates, we found that acetylation at the K44 site of CesA, a chaperone for the type-III secretion system (T3SS) translocator protein EspA, weakens its binding to EspA, thereby reducing the stability of this virulence factor; this PTM ultimately attenuating the virulence of EHEC O157:H7. Furthermore, we showed that deacetylation of the K44 site, which is deacetylated by CobB, promotes the interaction between CesA and EspA, thereby increasing bacterial virulence in vitro and in animal experiments. In summary, we showed that acetylation influences the virulence of EHEC O157:H7, and uncovered the mechanism by which CobB contributes to bacterial virulence based on the regulation of CesA deacetylation.

KEYWORDS:

• CobB
• deacetylation
• CesA
• EspA
• virulence
• EHEC

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

B. L. and M. W. designed the research; L. L., B. Y., J. W., Y. W., B. X., Y. L., W. L., P. W., Y. W., M. L., X. Z., R. L., G. M., and T. F. performed the experiments; L. L., B. Y., Y. W., J. Q., B. X. analyzed the data; and B. L., L. L., B. Y., J. W., and Y. W. wrote the manuscript.

Data availability statement

The relevant data are provided in the manuscript (Supplementary Information). MS proteomics data were deposited in the ProteomeXchange Consortium (http://proteomecentral.proteomexchange.org) via the iProX partner repository with the dataset identifier PXD045950.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/19490976.2024.2331435

Additional information

Funding

This work was supported by the National Natural Science Foundation of China Program under Grant No. 32070130, 81772148, 31820103002, 31770144, 81871624, and 32270191; Distinguished Young Scholars of Tianjin under Grant No. 20JCJQJC00180; the Natural Science Foundation of Shenzhen under Grant No. JCYJ20220530164604010, JCYJ20230807151559009; and Fundamental Research Funds for Central Universities under Grant No. 63233172.