Construction and characterization of a live, attenuated esrB mutant of Edwardsiella tarda and its potential as a vaccine against the haemorrhagic septicaemia in turbot, Scophthamus maximus (L.).
The esrB gene of Edwardsiella tarda, which encodes a regulator protein of the type III secretion system, was mutated by the unmarked deletion method and reintroduced by allelic exchange into the chromosome of E. tarda LSE40 by means of the suicide vector pRE112. The LSE40 esrB mutant was highly attenuated when inoculated intraperitoneally into turbot Scophthamus maximus L., showing a 50% lethal dose of 10(8.1)cfu/fish. The esrB mutants were not recoverable from the internal organs at 14 days post-inoculation. Vaccination with a single dose of 10(5)-10(7) cfu/fish of the esrB mutant elicited significant protection against the wild-type strain of E. tarda LSE40 (relative percentage survival>50%). The protection correlated well with the antibody titres in the serum of vaccinated fish.
Lan
Mo Zhao
MZ
Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China. zhlmo@ms.qdio.ac.cn
Peng
Xiao
X
Xiang
Mao Yun
MY
Xia
Zou Yu
ZY
Bo
Wang
W
Jie
Li
L
Li
Xu Yong
XY
Jun
Zhang Pei
ZP
D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000276:immunology*; D020609:Edwardsiella tarda / Q000235:genetics* / Q000276:immunology* / Q000472:pathogenicity; D004756:Enterobacteriaceae Infections / Q000276:immunology / Q000401:mortality / Q000517:prevention & control / Q000662:veterinary*; D005393:Fish Diseases / Q000276:immunology / Q000382:microbiology / Q000401:mortality / Q000517:prevention & control; D005412:Flatfishes / Q000276:immunology*; D006483:Hemorrhagic Septicemia / Q000401:mortality / Q000517:prevention & control / Q000662:veterinary*; D009154:Mutation / Q000235:genetics; D016019:Survival Analysis; D013997:Time Factors; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000276:immunology
D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D014613:Vaccines, Attenuated