Dual role of CsrA in regulating the hemolytic activity of Escherichia coli O157:H7
| Title: | Dual role of CsrA in regulating the hemolytic activity of Escherichia coli O157:H7 |
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| Authors: | Zhibin Sun, Ning Zhou, Wenting Zhang, Yan Xu, Yu-Feng Yao |
| Source: | Virulence, Vol 13, Iss 1, Pp 859-874 (2022) |
| Publisher Information: | Taylor & Francis Group, 2022. |
| Publication Year: | 2022 |
| Collection: | LCC:Infectious and parasitic diseases |
| Subject Terms: | Escherichia coli O157:H7, hemolysis, CsrA/RsmA, virulence, protein–RNA interaction, Infectious and parasitic diseases, RC109-216 |
| More Details: | Post-transcriptional global carbon storage regulator A (CsrA) is a sequence-specific RNA-binding protein involved in the regulation of multiple bacterial processes. Hemolysin is an important virulence factor in the enterohemorrhagic Escherichia coli O157:H7 (EHEC). Here, we show that CsrA plays a dual role in the regulation of hemolysis in EHEC. CsrA significantly represses plasmid-borne enterohemolysin (EhxA)-mediated hemolysis and activates chromosome-borne hemolysin E (HlyE)-mediated hemolysis through different mechanisms. RNA structure prediction revealed a well-matched stem-loop structure with two potential CsrA binding sites located on the 5' untranslated region (UTR) of ehxB, which encodes a translocator required for EhxA secretion. CsrA inhibits EhxA secretion by directly binding to the RNA leader sequence of ehxB to repress its expression in two different ways: CsrA either binds to the Shine–Dalgarno sequence of ehxB to block ribosome access or to ehxB transcript to promote its mRNA decay. The predicted CsrA-binding site 1 of ehxB is essential for its regulation. There is a single potential CsrA-binding site at the 5'-end of the hlyE transcript, and its mutation completely abolishes CsrA-dependent activation. CsrA can also stabilize hlyE mRNA by directly binding to its 5' UTR. Overall, our results indicate that CsrA acts as a hemolysis modulator to regulate pathogenicity under certain conditions. |
| Document Type: | article |
| File Description: | electronic resource |
| Language: | English |
| ISSN: | 21505594 2150-5608 2150-5594 |
| Relation: | https://doaj.org/toc/2150-5594; https://doaj.org/toc/2150-5608 |
| DOI: | 10.1080/21505594.2022.2073023 |
| Access URL: | https://doaj.org/article/a9e70a1361464c0e861c3ae553768da2 |
| Accession Number: | edsdoj.9e70a1361464c0e861c3ae553768da2 |
| Database: | Directory of Open Access Journals |
| ISSN: | 21505594 21505608 |
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| DOI: | 10.1080/21505594.2022.2073023 |
| Published in: | Virulence |
| Language: | English |