Cargando…

Functional characterization of two 3-dehydroquinases of AroQ1 and AroQ2 in the shikimate pathway and expression of genes for the type III secretion system in Ralstonia solanacearum

The shikimate pathway is a general route for the biosynthesis of aromatic amino acids (AAAs) in many microorganisms. A 3-dehydroquinase, AroQ, controls the third step of the shikimate pathway that catalyzes the formation of 3-dehydroquinate from 3-dehydroshikimate via a trans-dehydration reaction. R...

Descripción completa

Detalles Bibliográficos
Autores principales: Zhang, Qingshan, Wu, Bofan, Han, Liangliang, Yu, Duan, Liang, Tao, Wang, Yan, Guo, Tao
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10171560/
https://www.ncbi.nlm.nih.gov/pubmed/37180250
http://dx.doi.org/10.3389/fmicb.2023.1186688
_version_ 1785039445040300032
author Zhang, Qingshan
Wu, Bofan
Han, Liangliang
Yu, Duan
Liang, Tao
Wang, Yan
Guo, Tao
author_facet Zhang, Qingshan
Wu, Bofan
Han, Liangliang
Yu, Duan
Liang, Tao
Wang, Yan
Guo, Tao
author_sort Zhang, Qingshan
collection PubMed
description The shikimate pathway is a general route for the biosynthesis of aromatic amino acids (AAAs) in many microorganisms. A 3-dehydroquinase, AroQ, controls the third step of the shikimate pathway that catalyzes the formation of 3-dehydroquinate from 3-dehydroshikimate via a trans-dehydration reaction. Ralstonia solanacearum harbors two 3-dehydroquinases, AroQ1 and AroQ2, sharing 52% similarity in amino acids. Here, we demonstrated that two 3-dehydroquinases, AroQ1 and AroQ2, are essential for the shikimate pathway in R. solanacearum. The growth of R. solanacearum was completely diminished in a nutriment-limited medium with the deletion of both aroQ1 and aroQ2, while substantially impaired in planta. The aroQ1/2 double mutant was able to replicate in planta but grew slowly, which was ~4 orders of magnitude less than the parent strain to proliferate to the maximum cell densities in tomato xylem vessels. Moreover, the aroQ1/2 double mutant failed to cause disease in tomato and tobacco plants, whereas the deletion of either aroQ1 or aroQ2 did not alter the growth of R. solanacearum or pathogenicity on host plants. Supplementary shikimic acid (SA), an important intermediate of the shikimate pathway, substantially restored the diminished or impaired growth of aroQ1/2 double mutant in a limited medium or inside host plants. The necessity of AroQ1 and AroQ2 on the pathogenicity of solanacearum toward host plants was partially due to insufficient SA inside host plants. Moreover, the deletion of both aroQ1 and aroQ2 significantly impaired the expression of genes for the type III secretion system (T3SS) both in vitro and in planta. Its involvement in the T3SS was mediated through the well-characterized PrhA signaling cascade and was independent of growth deficiency under nutrient-limited conditions. Taken together, R. solanacearum 3-dehydroquinases play important roles in bacterial growth, the expression of the T3SS, and pathogenicity in host plants. These results could extend our insights into the understanding of the biological function of AroQ and the sophisticated regulation of the T3SS in R. solanacearum.
format Online
Article
Text
id pubmed-10171560
institution National Center for Biotechnology Information
language English
publishDate 2023
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-101715602023-05-11 Functional characterization of two 3-dehydroquinases of AroQ1 and AroQ2 in the shikimate pathway and expression of genes for the type III secretion system in Ralstonia solanacearum Zhang, Qingshan Wu, Bofan Han, Liangliang Yu, Duan Liang, Tao Wang, Yan Guo, Tao Front Microbiol Microbiology The shikimate pathway is a general route for the biosynthesis of aromatic amino acids (AAAs) in many microorganisms. A 3-dehydroquinase, AroQ, controls the third step of the shikimate pathway that catalyzes the formation of 3-dehydroquinate from 3-dehydroshikimate via a trans-dehydration reaction. Ralstonia solanacearum harbors two 3-dehydroquinases, AroQ1 and AroQ2, sharing 52% similarity in amino acids. Here, we demonstrated that two 3-dehydroquinases, AroQ1 and AroQ2, are essential for the shikimate pathway in R. solanacearum. The growth of R. solanacearum was completely diminished in a nutriment-limited medium with the deletion of both aroQ1 and aroQ2, while substantially impaired in planta. The aroQ1/2 double mutant was able to replicate in planta but grew slowly, which was ~4 orders of magnitude less than the parent strain to proliferate to the maximum cell densities in tomato xylem vessels. Moreover, the aroQ1/2 double mutant failed to cause disease in tomato and tobacco plants, whereas the deletion of either aroQ1 or aroQ2 did not alter the growth of R. solanacearum or pathogenicity on host plants. Supplementary shikimic acid (SA), an important intermediate of the shikimate pathway, substantially restored the diminished or impaired growth of aroQ1/2 double mutant in a limited medium or inside host plants. The necessity of AroQ1 and AroQ2 on the pathogenicity of solanacearum toward host plants was partially due to insufficient SA inside host plants. Moreover, the deletion of both aroQ1 and aroQ2 significantly impaired the expression of genes for the type III secretion system (T3SS) both in vitro and in planta. Its involvement in the T3SS was mediated through the well-characterized PrhA signaling cascade and was independent of growth deficiency under nutrient-limited conditions. Taken together, R. solanacearum 3-dehydroquinases play important roles in bacterial growth, the expression of the T3SS, and pathogenicity in host plants. These results could extend our insights into the understanding of the biological function of AroQ and the sophisticated regulation of the T3SS in R. solanacearum. Frontiers Media S.A. 2023-04-26 /pmc/articles/PMC10171560/ /pubmed/37180250 http://dx.doi.org/10.3389/fmicb.2023.1186688 Text en Copyright © 2023 Zhang, Wu, Han, Yu, Liang, Wang and Guo. https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Microbiology
Zhang, Qingshan
Wu, Bofan
Han, Liangliang
Yu, Duan
Liang, Tao
Wang, Yan
Guo, Tao
Functional characterization of two 3-dehydroquinases of AroQ1 and AroQ2 in the shikimate pathway and expression of genes for the type III secretion system in Ralstonia solanacearum
title Functional characterization of two 3-dehydroquinases of AroQ1 and AroQ2 in the shikimate pathway and expression of genes for the type III secretion system in Ralstonia solanacearum
title_full Functional characterization of two 3-dehydroquinases of AroQ1 and AroQ2 in the shikimate pathway and expression of genes for the type III secretion system in Ralstonia solanacearum
title_fullStr Functional characterization of two 3-dehydroquinases of AroQ1 and AroQ2 in the shikimate pathway and expression of genes for the type III secretion system in Ralstonia solanacearum
title_full_unstemmed Functional characterization of two 3-dehydroquinases of AroQ1 and AroQ2 in the shikimate pathway and expression of genes for the type III secretion system in Ralstonia solanacearum
title_short Functional characterization of two 3-dehydroquinases of AroQ1 and AroQ2 in the shikimate pathway and expression of genes for the type III secretion system in Ralstonia solanacearum
title_sort functional characterization of two 3-dehydroquinases of aroq1 and aroq2 in the shikimate pathway and expression of genes for the type iii secretion system in ralstonia solanacearum
topic Microbiology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10171560/
https://www.ncbi.nlm.nih.gov/pubmed/37180250
http://dx.doi.org/10.3389/fmicb.2023.1186688
work_keys_str_mv AT zhangqingshan functionalcharacterizationoftwo3dehydroquinasesofaroq1andaroq2intheshikimatepathwayandexpressionofgenesforthetypeiiisecretionsysteminralstoniasolanacearum
AT wubofan functionalcharacterizationoftwo3dehydroquinasesofaroq1andaroq2intheshikimatepathwayandexpressionofgenesforthetypeiiisecretionsysteminralstoniasolanacearum
AT hanliangliang functionalcharacterizationoftwo3dehydroquinasesofaroq1andaroq2intheshikimatepathwayandexpressionofgenesforthetypeiiisecretionsysteminralstoniasolanacearum
AT yuduan functionalcharacterizationoftwo3dehydroquinasesofaroq1andaroq2intheshikimatepathwayandexpressionofgenesforthetypeiiisecretionsysteminralstoniasolanacearum
AT liangtao functionalcharacterizationoftwo3dehydroquinasesofaroq1andaroq2intheshikimatepathwayandexpressionofgenesforthetypeiiisecretionsysteminralstoniasolanacearum
AT wangyan functionalcharacterizationoftwo3dehydroquinasesofaroq1andaroq2intheshikimatepathwayandexpressionofgenesforthetypeiiisecretionsysteminralstoniasolanacearum
AT guotao functionalcharacterizationoftwo3dehydroquinasesofaroq1andaroq2intheshikimatepathwayandexpressionofgenesforthetypeiiisecretionsysteminralstoniasolanacearum