hrp genes of Erwinia chrysanthemi 3937 are important virulence factors
Related Experiment Video
Updated: Oct 1, 2026

Single-Cell Analysis of the Expression of Pseudomonas syringae Genes within the Plant Tissue
Published on: October 6, 2022
Ching-Hong Yang1, Marina Gavilanes-Ruiz, Yasushi Okinaka
1Department of Plant Pathology, University of California, Riverside 92521, USA.
Abstract:
We developed improved virulence assays for Erwinia chrysanthemi 3937 on African violet varieties and devised a new method for the construction of precise bacterial gene knockouts. These methods were tested by constructing mutations in genes suspected to be involved with plant interactions. The virulence of the hrpG and hrcC mutant strains (both gene products presumed to be involved in protein secretion) was greatly reduced on leaves of semitolerant African violet varieties. An hrpN mutant strain produced delayed symptoms on African violet leaves and an hrpN delta pel (delta pel = five major pectate lyase genes deleted) double mutant was nonpathogenic. The hrcC and hrpG mutants did not produce a rapid hypersensitive response (HR) in tobacco, unlike the wild-type bacterium, and the hrpN mutant gave a reduced HR. The results, therefore, establish the importance of hrp genes in the virulence of E. chrysanthemi and their ability to elicit HR on nonhosts. The data also suggest that other effector proteins secreted by the Hrp system are required for full virulence and HR elicitation.
More Related Videos
08:34Generation of In-Frame Gene Deletion Mutants in Pseudomonas aeruginosa and Testing for Virulence Attenuation in a Simple Mouse Model of Infection
Published on: January 8, 2020
07:58Laboratory Techniques Used to Maintain and Differentiate Biotypes of Vibrio cholerae Clinical and Environmental Isolates
Published on: May 30, 2017
Related Concept Videos
Regulation of Bacterial Virulence
Determinants of Bacterial Pathogenicity and Virulence
Stringent Response in E. coli
Gene Regulation in Microbial Communities: Quorum Sensing
Plasmids
Bacterial Gastroenteritis