Quorum-sensing contributes to virulence, twitching motility, seed attachment and biofilm formation in the wild type strain Aac-5 of Acidovorax citrulli.
Acidovorax citrulli is a seed-borne pathogen causing bacterial fruit blotch of cucurbits including melon and watermelon. We investigated the roles of quorum sensing in the wild-type group II strain Aac-5 of A. citrulli by generating aacR and aacI knockout mutants and their complementation strains. We found that twitching motility and virulence were reduced, but biofilm formation and seed attachment were increased significantly in the two mutants as compared to the wild type strain. Deletion of aacR and aacI, however, had no effect on swimming motility and polar flagella formation of Aac-5. Furthermore, deletion of aacR resulted in reduced gene expression of hrpE, hrcN and pilT, while deletion of aacI affected only the expression of hrpE and pilT, not hrcN.
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China; National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, State Key Laboratory Breeding Base of Dao-di Herbs, Beijng, 100700, China. Electronic address: wtl82@163.com.
Tielin
T
Wang
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China. Electronic address: wyngwan@yahoo.com.
Wei
W
Guan
Floral and Nursery Plants Research Unit, Agricultural Research Service, U. S. Dept. of Agriculture, Beltsville, Maryland, USA. Electronic address: qi.huang@ars.usda.gov.
Qi
Q
Huang
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China. Electronic address: yangyuwen@126.com.
Yuwen
Y
Yang
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China. Electronic address: yanwanrong818@163.com.
Wanrong
W
Yan
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China. Electronic address: baixin_2008@163.com.
Baixin
B
Sun
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China. Electronic address: tingchangzhao@gmail.com.
Tingchang
T
Zhao
D001422:Bacterial Adhesion; D018441:Biofilms / Q000254:growth & development*; D029773:Citrullus / Q000382:microbiology; D042621:Comamonadaceae / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D020869:Gene Expression Profiling; D005816:Genetic Complementation Test; D008124:Locomotion; D053038:Quorum Sensing; D012639:Seeds / Q000382:microbiology*; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics
D037521:Virulence Factors
Acidovorax citrulli; Biofilm formation; Quorum sensing; Twitching motility