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Chitinase A, a tightly regulated virulence factor of Salmonella enterica serovar Typhimurium, is actively secreted by a Type 10 Secretion System
As a facultative intracellular pathogen, Salmonella enterica serovar Typhimurium is one of the leading causes of food-borne diseases in humans. With the ingestion of fecal contaminated food or water, S. Typhimurium reaches the intestine. Here, the pathogen efficiently invades intestinal epithelial c...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2023
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10109510/ https://www.ncbi.nlm.nih.gov/pubmed/37018381 http://dx.doi.org/10.1371/journal.ppat.1011306 |
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author | Krone, Lena Faass, Larissa Hauke, Martina Josenhans, Christine Geiger, Tobias |
author_facet | Krone, Lena Faass, Larissa Hauke, Martina Josenhans, Christine Geiger, Tobias |
author_sort | Krone, Lena |
collection | PubMed |
description | As a facultative intracellular pathogen, Salmonella enterica serovar Typhimurium is one of the leading causes of food-borne diseases in humans. With the ingestion of fecal contaminated food or water, S. Typhimurium reaches the intestine. Here, the pathogen efficiently invades intestinal epithelial cells of the mucosal epithelium by the use of multiple virulence factors. Recently, chitinases have been described as emerging virulence factors of S. Typhimurium that contribute to the attachment and invasion of the intestinal epithelium, prevent immune activation, and modulate the host glycome. Here we find that the deletion of chiA leads to diminished adhesion and invasion of polarized intestinal epithelial cells (IEC) compared to wild-type S. Typhimurium. Interestingly, no apparent impact on interaction was detected when using non-polarized IEC or HeLa epithelial cells. In concordance, we demonstrate that chiA gene and ChiA protein expression was solely induced when bacteria gain contact with polarized IEC. The induction of chiA transcripts needs the specific activity of transcriptional regulator ChiR, which is co-localized with chiA in the chitinase operon. Moreover, we established that after chiA is induced, a major portion of the bacterial population expresses chiA, analyzed by flow cytometry. Once expressed, we found ChiA in the bacterial supernatants using Western blot analyses. ChiA secretion was completely abolished when accessory genes within the chitinase operon encoding for a holin and a peptidoglycan hydrolase were deleted. Holins, peptidoglycan hydrolases, and large extracellular enzymes in close proximity have been described as components of the bacterial holin/peptidoglycan hydrolase-dependent protein secretion system or Type 10 Secretion System. Overall, our results confirm that chitinase A is an important virulence factor, tightly regulated by ChiR, that promotes adhesion and invasion upon contact with polarized IEC and is likely secreted by a Type 10 Secretion System (T10SS). |
format | Online Article Text |
id | pubmed-10109510 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2023 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-101095102023-04-18 Chitinase A, a tightly regulated virulence factor of Salmonella enterica serovar Typhimurium, is actively secreted by a Type 10 Secretion System Krone, Lena Faass, Larissa Hauke, Martina Josenhans, Christine Geiger, Tobias PLoS Pathog Research Article As a facultative intracellular pathogen, Salmonella enterica serovar Typhimurium is one of the leading causes of food-borne diseases in humans. With the ingestion of fecal contaminated food or water, S. Typhimurium reaches the intestine. Here, the pathogen efficiently invades intestinal epithelial cells of the mucosal epithelium by the use of multiple virulence factors. Recently, chitinases have been described as emerging virulence factors of S. Typhimurium that contribute to the attachment and invasion of the intestinal epithelium, prevent immune activation, and modulate the host glycome. Here we find that the deletion of chiA leads to diminished adhesion and invasion of polarized intestinal epithelial cells (IEC) compared to wild-type S. Typhimurium. Interestingly, no apparent impact on interaction was detected when using non-polarized IEC or HeLa epithelial cells. In concordance, we demonstrate that chiA gene and ChiA protein expression was solely induced when bacteria gain contact with polarized IEC. The induction of chiA transcripts needs the specific activity of transcriptional regulator ChiR, which is co-localized with chiA in the chitinase operon. Moreover, we established that after chiA is induced, a major portion of the bacterial population expresses chiA, analyzed by flow cytometry. Once expressed, we found ChiA in the bacterial supernatants using Western blot analyses. ChiA secretion was completely abolished when accessory genes within the chitinase operon encoding for a holin and a peptidoglycan hydrolase were deleted. Holins, peptidoglycan hydrolases, and large extracellular enzymes in close proximity have been described as components of the bacterial holin/peptidoglycan hydrolase-dependent protein secretion system or Type 10 Secretion System. Overall, our results confirm that chitinase A is an important virulence factor, tightly regulated by ChiR, that promotes adhesion and invasion upon contact with polarized IEC and is likely secreted by a Type 10 Secretion System (T10SS). Public Library of Science 2023-04-05 /pmc/articles/PMC10109510/ /pubmed/37018381 http://dx.doi.org/10.1371/journal.ppat.1011306 Text en © 2023 Krone et al https://creativecommons.org/licenses/by/4.0/This is an open access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
spellingShingle | Research Article Krone, Lena Faass, Larissa Hauke, Martina Josenhans, Christine Geiger, Tobias Chitinase A, a tightly regulated virulence factor of Salmonella enterica serovar Typhimurium, is actively secreted by a Type 10 Secretion System |
title | Chitinase A, a tightly regulated virulence factor of Salmonella enterica serovar Typhimurium, is actively secreted by a Type 10 Secretion System |
title_full | Chitinase A, a tightly regulated virulence factor of Salmonella enterica serovar Typhimurium, is actively secreted by a Type 10 Secretion System |
title_fullStr | Chitinase A, a tightly regulated virulence factor of Salmonella enterica serovar Typhimurium, is actively secreted by a Type 10 Secretion System |
title_full_unstemmed | Chitinase A, a tightly regulated virulence factor of Salmonella enterica serovar Typhimurium, is actively secreted by a Type 10 Secretion System |
title_short | Chitinase A, a tightly regulated virulence factor of Salmonella enterica serovar Typhimurium, is actively secreted by a Type 10 Secretion System |
title_sort | chitinase a, a tightly regulated virulence factor of salmonella enterica serovar typhimurium, is actively secreted by a type 10 secretion system |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10109510/ https://www.ncbi.nlm.nih.gov/pubmed/37018381 http://dx.doi.org/10.1371/journal.ppat.1011306 |
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