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Volume 159, Issue Pt_8

Functional analysis of PrhG regulating the regulon in host plants Free

Abstract

Genes in the regulon encode component proteins of the type III secretion system and are essential for the pathogenicity of . The regulon is controlled by HrpB. We isolated several genes regulating expression from the Japanese strain OE1-1 using minitransposon mutagenesis. Among them, we mainly focused on two genes, and , which are the positive regulators of . Although the global virulence regulator PhcA negatively regulated expression via , it positively regulated expression. We further investigated the contrasting regulation of and by PhcA and speculated that may switch from HrpG to PrhG for activation in a cell density-dependent manner. Although the mutant proliferated similarly to the wild-type in leaf intercellular spaces and in xylem vessels of the host plants, it was less virulent than the wild-type. The expression of the operon, which belongs to the regulon, was significantly reduced in the mutant by more than half in the leaf intercellular spaces and more than two-thirds in the xylem vessels when compared with the wild-type.

  • Received:
  • Accepted:
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2013-08-01
2024-04-27
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Functional analysis of Ralstonia solanacearum PrhG regulating the hrp regulon in host plants
Microbiology 159, 1695 (2013); https://doi.org/10.1099/mic.0.067819-0
/content/journal/micro/10.1099/mic.0.067819-0
/content/journal/micro/10.1099/mic.0.067819-0
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