Sucrose and malic acid in the tobacco plant induce <i>hrp</i> regulon in a phytopathogen <i>Ralstonia pseudosolanacearum</i>.

ABSTRACT: Genes encoding a type III secretion system in Ralstonia pseudosolanacearum are regulated by HrpB as an hrp regulon and induced only in plants. This study aimed to identify the plant signals that induce the hrp regulon and confirm the signal recognition mechanism. Signaling molecules that induce hrpB expression were screened using resting cells of the hrpB-lacZ reporter strain. Only the soluble fraction of smashed tobacco seedlings induced hrpB expression. The heated soluble fraction retained its hrpB-inducing activity, indicating that the signaling molecules were not proteins. When the soluble fraction was fractionated into acidic, neutral, and basic components, both the acidic and neutral fractions induced hrpB expression. As neutral

SUBMITTER: Cao Y 

PROVIDER: S-EPMC11925246 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature