RRC ID 3221
著者 Mukaihara T, Tamura N, Murata Y, Iwabuchi M.
タイトル Genetic screening of Hrp type III-related pathogenicity genes controlled by the HrpB transcriptional activator in Ralstonia solanacearum.
ジャーナル Mol Microbiol
Abstract As in many other Gram-negative phytopathogenic bacteria, the Hrp type III secretion system is essential for the pathogenicity of Ralstonia solanacearum on host plants. The expression of most of the type III effector genes previously isolated from R. solanacearum is co-regulated with those of hrp genes by an AraC-type transcriptional activator, HrpB. In order to isolate type III-related pathogenicity genes, we screened hrpB-regulated genes in R. solanacearum. Using a transposon-based system, we isolated 30 novel hpx (hrpB-dependent expression) genes outside the hrp gene cluster. Most of the hpx genes contain a PIP (plant-inducible promoter) box-like motif in their putative promoter regions. Seven hpx genes encoded homologues of known type III effectors and type III-related proteins found in other animal and plant pathogens. Four encoded known enzymes, namely, glyoxalase I, Nudix hydrolase, spermidine synthase and transposase. Interestingly, six hpx genes encoded two types of leucine-rich repeat (LRR) protein. Products of the remaining genes did not show any significant homology to known proteins. We also identified two novel hrpB-regulated genes, hpaZ and hpaB, downstream of hrpY in the hrp cluster. The hpaB gene of R. solanacearum, but not hpaZ, was required for both the pathogenicity and ability to induce hypersensitive reaction on plants. We show that a hpaB null mutant still produces Hrp pili on the cell surface although it shows a typical Hrp-defective phenotype on plants.
巻・号 54(4)
ページ 863-75
公開日 2004-11-1
DOI 10.1111/j.1365-2958.2004.04328.x
PII MMI4328
PMID 15522073
MeSH Bacterial Proteins / genetics Bacterial Proteins / metabolism* DNA Transposable Elements DNA-Binding Proteins / genetics DNA-Binding Proteins / metabolism* Fimbriae, Bacterial / metabolism Gene Expression Regulation, Bacterial* Genes, Reporter Molecular Sequence Data Multigene Family Mutation Open Reading Frames Phenotype Ralstonia solanacearum / genetics* Ralstonia solanacearum / metabolism Ralstonia solanacearum / pathogenicity Ralstonia solanacearum / ultrastructure Tobacco / microbiology Trans-Activators / genetics Trans-Activators / metabolism* Transcription Factors / genetics Transcription Factors / metabolism* Transcription, Genetic
IF 3.418
引用数 75
WOS 分野 MICROBIOLOGY BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
原核生物(大腸菌) CV-41(JM109)? CV-61(S17-1)