title: Evaluation of a Brucella melitensis mutant deficient in O-polysaccharide export system ATP-binding protein as a rough vaccine candidate.
abstract: Rough Brucella mutants have been sought as vaccine candidates that do not interfere with the conventional serological diagnosis of brucellosis. In this study, a rough mutant of Brucella melitensis was generated by the disruption of the wzt gene, which encodes the O-polysaccharide (O-PS) export system ATP-binding protein. In vivo, the mutant 16MΔwzt was attenuated and conferred a level of protection against B. melitensis 16M challenge similar to that conferred by the vaccine strain B. melitensis M5 in mice. In pregnant sheep, the mutant 16MΔwzt did not induce abortion. In vitro, 16MΔwzt was more susceptible to polymyxin B and complement-mediated killing than B. melitensis 16M was. Most importantly, although 16MΔwzt had a rough phenotype, it was able to synthesize O-PS and did not induce detectable specific antibodies in sheep. These results suggested that 16MΔwzt deserved to further systematic evaluation as a vaccine for target animal hosts due to its promising features.
authors.affiliation: Animal Science and Technology College, Beijing University of Agriculture, Beinong Road 7, Huilongguan, Changping District, Beijing 102206, China; Key Laboratory of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan Xilu No. 2, Haidian District, Beijing 100193, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan Xilu No. 2, Haidian District, Beijing 100193, China.
authors.forename: Jian Rui
authors.initials: JR
authors.lastname: Niu
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan Xilu No. 2, Haidian District, Beijing 100193, China.
authors.forename: Xiao Lei
authors.initials: XL
authors.lastname: Wang
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan Xilu No. 2, Haidian District, Beijing 100193, China.
authors.forename: Tong Lei
authors.initials: TL
authors.lastname: Wu
authors.affiliation: Animal Science and Technology College, Beijing University of Agriculture, Beinong Road 7, Huilongguan, Changping District, Beijing 102206, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Cheng
authors.affiliation: Animal Science and Technology College, Beijing University of Agriculture, Beinong Road 7, Huilongguan, Changping District, Beijing 102206, China. Electronic address: lulin1209@163.com.
authors.forename: Lin
authors.initials: L
authors.lastname: Lu
authors.affiliation: Key Laboratory of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan Xilu No. 2, Haidian District, Beijing 100193, China. Electronic address: wuqm@cau.edu.cn.
authors.forename: Qing Min
authors.initials: QM
authors.lastname: Wu
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000172:deficiency*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins; D001770:Blood Bactericidal Activity; D002004:Brucella Vaccine / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D017347:Brucella melitensis / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity / Q000502:physiology; D002006:Brucellosis / Q000517:prevention & control*; D004195:Disease Models, Animal; D005260:Female; D017353:Gene Deletion; D008807:Mice, Inbred BALB C; D050296:Microbial Viability / Q000187:drug effects; D019081:O Antigens / Q000378:metabolism*; D011112:Polymyxin B / Q000494:pharmacology; D011247:Pregnancy; D012756:Sheep; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology
chemical_list: D018528:ATP-Binding Cassette Transporters; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002004:Brucella Vaccine; D019081:O Antigens; D014613:Vaccines, Attenuated; C108433:Wzt protein, bacteria; D011112:Polymyxin B
keywords: Brucella melitensis; O-PS export system ATP-binding protein; Rough mutant; Vaccine candidate