MvaT binds to the P exsC promoter to repress the type III secretion system in Pseudomonas aeruginosa

Liwen Yin; Qi Liu; Xiaolei Pan; Chenjing Lv; Yuxi Bai; Fang Bai; Zhihui Cheng; Weihui Wu; Un-Hwan Ha; Yongxin Jin

doi:10.3389/fcimb.2023.1267748

MvaT binds to the P _exsC promoter to repress the type III secretion system in Pseudomonas aeruginosa

Front Cell Infect Microbiol. 2023 Nov 6:13:1267748. doi: 10.3389/fcimb.2023.1267748. eCollection 2023.

Authors

Liwen Yin¹, Qi Liu¹, Xiaolei Pan¹, Chenjing Lv¹, Yuxi Bai¹, Fang Bai¹, Zhihui Cheng¹, Weihui Wu¹, Un-Hwan Ha², Yongxin Jin¹

Affiliations

¹ State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China.
² Department of Biotechnology and Bioinformatics, Korea University, Sejong, Republic of Korea.

Abstract

Pseudomonas aeruginosa is an opportunistic human pathogen capable of causing a variety of acute and chronic infections. Its type III secretion system (T3SS) plays a critical role in pathogenesis during acute infection. ExsA is a master regulator that activates the expression of all T3SS genes. Transcription of exsA is driven by two distinct promoters, its own promoter P_exsA and its operon promoter P_exsC. Here, in combination with a DNA pull-down assay and mass spectrometric analysis, we found that a histone-like nucleoid-structuring (H-NS) family protein MvaT can bind to the P_exsC promoter. Using EMSA and reporter assays, we further found that MvaT directly binds to the P_exsC promoter to repress the expression of T3SS genes. The repression of MvaT on P_exsC is independent of ExsA, with MvaT binding to the -429 to -380 bp region relative to the transcription start site of the exsC gene. The presented work further reveals the complex regulatory network of the T3SS in P. aeruginosa.

Keywords: MvaT; P. aeruginosa; PexsA; PexsC; T3SS; transcriptional regulation.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bacterial Proteins / metabolism
Gene Expression Regulation, Bacterial
Humans
Promoter Regions, Genetic
Pseudomonas aeruginosa / genetics
Pseudomonas aeruginosa / metabolism
Trans-Activators* / genetics
Type III Secretion Systems* / genetics
Type III Secretion Systems* / metabolism

Substances

Type III Secretion Systems
Trans-Activators
Bacterial Proteins

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by the National Key Research and Development Project of China (2021YFE0201300 and 2021YFE0101700), the Science and Technology Committee of Tianjin (22JCYBJC00790 and 22JCYBJC00560), the National Science Foundation of China (31970179, 31970680, 32170177, 82061148018, and 32170199), and the Fundamental Research Funds for the Central Universities, Nankai University (63231048 and 63231047). The funders had no role in the study design, data collection and interpretation, or the decision to submit the work for publication.