Inhibitory effect and mode of action of chitosan solution against rice bacterial brown stripe pathogen Acidovorax avenae subsp. avenae RS-1.
Inhibitory effect and mode of action of chitosan solution against rice bacterial brown stripe pathogen Acidovorax avenae subsp. avenae (Aaa) strain RS-1 was examined in this study. Result from this study indicated that chitosan solutions at 0.10, 0.20, and 0.40mg/mL inhibited the in vitro growth of Aaa strain RS-1, and in general the inhibitory efficiency increased with the increase of both chitosan concentration and the incubation time. Antibacterial activity of chitosan in this study may be mainly due to the damage of cell membrane, which was evidenced by both the cell lysis observed by transmission electron microscopy, and the increased release of cell materials based on the measurement of cell membrane integrity. Furthermore, chitosan solutions at concentrations of 0.1, 0.2, and 0.4mg/mL markedly inhibited bacterial biofilm formation compared to the control, and the inhibitory effect increased with the increase of chitosan concentration. In addition, quantitative real-time PCR of the 10 secretion system related genes revealed the differential expression of genes in particular ompA/motB, emphasizing the importance of this gene in the response of Aaa strain RS-1 to chitosan stress. These results indicated that the antibacterial mode of action of chitosan may be mainly due to membrane disruption and lysis, reduction of biofilm formation, and gene expression change. Overall, the results clearly indicated that chitosan had the potential to control bacterial brown stripe of rice.
State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, 310058 Hangzhou, China.
Chunlan
C
Yang
State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, 310058 Hangzhou, China. Electronic address: libin0571@zju.edu.cn.
Bin
B
Li
State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, 310058 Hangzhou, China.
Mengyu
M
Ge
State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, 310058 Hangzhou, China.
Kaile
K
Zhou
State Key Laboratory Breeding Base for Zhejiang Sustainable Plant Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, 310021 Hangzhou, China.
Yanli
Y
Wang
State Key Laboratory of Rice Biology, China National Rice Research Institute, 310006 Hangzhou, China.
Ju
J
Luo
Department of Biosciences, COMSATS Institute of Information Technology, Sahiwal Campus, Sahiwal, Pakistan.
Muhammad
M
Ibrahim
State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, 310058 Hangzhou, China.
Guanlin
G
Xie
State Key Laboratory Breeding Base for Zhejiang Sustainable Plant Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, 310021 Hangzhou, China. Electronic address: sungc01@sina.com.
Guochang
G
Sun
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D048271:Chitosan / Q000737:chemistry / Q000494:pharmacology*; D042621:Comamonadaceae / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D008826:Microbial Sensitivity Tests; D012275:Oryza / Q000382:microbiology*; D012996:Solutions; D013329:Structure-Activity Relationship
D000900:Anti-Bacterial Agents; D012996:Solutions; D048271:Chitosan
A. avenae subsp. avenae; Antibacterial activity; Biofilm; Chitosan; Gene expression; qRT-PCR