RRC ID 3286
Author Murata Y, Tamura N, Nakaho K, Mukaihara T.
Title Mutations in the lrpE gene of Ralstonia solanacearum affects Hrp pili production and virulence.
Journal Mol Plant Microbe Interact
Abstract The Ralstonia solanacearum hrpB-regulated gene lrpE (hpx5/brg24) encodes a PopC-like leucine-rich repeat (LRR) protein that carries 11 tandem LRR in the central region. Defects in the lrpE gene slightly reduced the virulence of R. solanacearum on host plants and changed the bacterial morphology leading to the formation of large aggregates in a minimal medium. The aggregation in the deltalrpE background required the presence of a functional Hrp type III secretion system. In wild-type R. solanacearum, Hrp pili disappeared from the bacterial surface at the end of the exponential growth phase, when the pili form into long bundles. However, even in the late growth phase, bundled Hrp pili were still observed on the cell surface of the deltalrpE mutant. Such bundles were entangled and anchored the mutant cells in the aggregates. In contrast to PopC, LrpE accumulated in bacterial cells and did not translocate into plant cells as an effector protein. The expression levels of hrp genes increased three- to fivefold in the deltalrpE background compared with those in the wild type. We propose that LrpE may negatively regulate the production of Hrp pili on the cell surface of R. solanacearum to disperse bacterial cells from aggregates. In turn, dispersal may contribute to the movement of the pathogen in the plant vascular system and, as a consequence, the pathogenicity of R. solanacearum.
Volume 19(8)
Pages 884-95
Published 2006-8-1
DOI 10.1094/MPMI-19-0884
PMID 16903354
MeSH Amino Acid Motifs Amino Acid Sequence Bacterial Proteins / chemistry Bacterial Proteins / genetics* Fimbriae, Bacterial / physiology* Fimbriae, Bacterial / ultrastructure Molecular Sequence Data Mutation* Ralstonia solanacearum / genetics Ralstonia solanacearum / metabolism Ralstonia solanacearum / pathogenicity* Sequence Alignment Solanum melongena / anatomy & histology Solanum melongena / microbiology Virulence / genetics
IF 3.696
Times Cited 11
WOS Category PLANT SCIENCES BIOTECHNOLOGY & APPLIED MICROBIOLOGY BIOCHEMISTRY & MOLECULAR BIOLOGY
Resource
Prokaryotes E. coli CV-41(JM109) CV-61(S17-1)