摘要
青枯菌Ralstonia solanacearum是全球作物生产中的一种重要病原细菌。由青枯菌引起的植物细菌性枯萎病(简称青枯病)危害数百种经济作物并造成严重经济损失。环二鸟苷酸(cyclic diguanylate,c-di-GMP)是一种广泛存在于细菌中的第二信使分子,通过调控生物膜形成、运动性等影响病原菌致病力。但在青枯菌中,c-di-GMP的调控网络并不清楚。本试验以青枯菌GMI 1000中的c-di-GMP降解酶基因gedrG缺失突变体菌株(ΔgedrG-GMI)为研究对象,将pMiniHimarI RB1质粒通过双亲共结合法导入ΔgedrG-GMI突变体,筛选运动性表型恢复的转座子插入突变体(transposon mutagenesis),共鉴定了13272株转座子插入突变体。其中,转座子插入vsrD基因时,ΔgedrG-GMI运动性恢复为野生型水平。分析表明vsrD基因缺失后,突变株运动性极显著增强,胞内c-di-GMP水平降低,致病力丧失,vsrD基因互补菌株运动性恢复至缺失前水平。以上结果表明,vsrD参与了青枯菌GMI 1000中c-di-GMP调控通路,影响GMI 1000运动性,且与致病性密切相关。
Ralstonia solanacearum is an important pathogen in crop production worldwide.The bacterial wilt caused by R.solanacearum affects hundreds of crops and causes serious economic losses.Cyclic diguanylate(c-di-GMP)is a widely distributed second messenger molecule in bacteria,which can regulate biofilm formation,motility,and other factors that affect pathogenicity.However,the regulatory network of c-di-GMP in R.solanacearum remains unclear.In this study,the c-di-GMP degrading enzyme gene gedrG deletion mutant strainΔgedrG-GMI was used as test object.The pMiniHimar1 RB1 plasmid was introduced into theΔgedrG-GMI mutant by biparental conjugation.Transposon mutagenesis was used to screen for mutants with recovered motility phenotypes.A total of 13272 transposon mutants were identified.When the transposon inserted into the vsrD gene,motility inΔgedrG-GMI was restored.Analysis showed that the deletion of vsrD resulted in significantly enhanced motility,reduced intracellular c-di-GMP levels,and loss of virulence.However,the motility of the vsrD complementation strain was restored to the pre-deletion level,but virulence was not restored.These results indicate that vsrD is involved in the regulation of the c-di-GMP pathway in R.solanacearum GMI 1000 and is closely related to its pathogenic mechanism.
作者
杨晓欣
许景升
徐进
韩文超
李志明
冯洁
YANG Xiaoxin;XU Jingsheng;XU Jin;HAN Wenchao;LI Zhiming;FENG Jie(State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences,Beijing 100193,China)
出处
《植物保护》
北大核心
2025年第3期102-112,共11页
Plant Protection
基金
国家重点研发计划(2021YFD1400200)。
作者简介
通信作者:冯洁,E-mail:jfeng@ippcaas.cn。
