title: Identification of putative virulence-associated genes among Haemophilus parasuis strains and the virulence difference of different serovars.
abstract: This study was aimed at determining virulence-associated genes among Haemophilus parasuis (H. parasuis) strains, and supplying for the Kielstein-Rapp-Gabrielson serotyping scheme. The subtractive fragments, obtained through suppression subtractive hybridization and reverse Southern blot hybridization, were found to encode genes representative of 7 different functions. PCR was used to investigate the distribution of these fragments in H. parasuis strains isolated from different infection sites in pigs. Mice challenge was then used to analyze the correlationship between subtractive fragments, infection sites and bacterial virulence. Eight weeks old female BALB/c mice (10 mice/group) were inoculated intraperitoneally with 3.0 × 10(9) CFU suspension (0.5 ml/mouse) of H. parasuis strains in PBS. Results indicated that H. parasuis possessed varied virulence even among the same serovar strains. Transcription units hsdR, hsdS, gpT and ompP2, identified from the subtractive fragments, were uniformly expressed in highly virulent strains, while absent in weakly virulent strains, and demonstrated variable degrees of expression in moderately virulent strains. Moreover, H. parasuis strains, isolated from pericardium and heart blood, were all highly virulent strains, while from nasal cavity and joint were moderately or weakly virulent strains. This study indicated that fragments hsdR, hsdS, gpT and ompP2 were associated with the virulence of H. parasuis. The virulence of H. parasuis strains isolated from different infection sites was different. The current research provides a new reference for determining bacterial virulence in different H. parasuis strains.
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China; Shandong Normal University, Jinan 250014, China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Yu
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Jiaqiang
authors.initials: J
authors.lastname: Wu
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Yuyu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Yijun
authors.initials: Y
authors.lastname: Du
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Peng
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Chen
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Wenbo
authors.initials: W
authors.lastname: Sun
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Cong
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Shaojian
authors.initials: S
authors.lastname: Xu
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Jianli
authors.initials: J
authors.lastname: Shi
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Baohua
authors.initials: B
authors.lastname: Huang
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China.
authors.forename: Xiwang
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Shandong Academy of Agricultural Sciences, Jinan 250100, China; Shandong Key Lab of Animal Disease Control and Breeding, Jinan 250100, China; Shandong Normal University, Jinan 250014, China. Electronic address: jinbaowang@aliyun.com.
authors.forename: Jinbao
authors.initials: J
authors.lastname: Wang
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005798:Genes, Bacterial; D006192:Haemophilus Infections / Q000382:microbiology / Q000473:pathology; D044137:Haemophilus parasuis / Q000145:classification* / Q000235:genetics*; D008807:Mice, Inbred BALB C; D065288:Serogroup; D012703:Serotyping / Q000379:methods; D013552:Swine; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D037521:Virulence Factors
keywords: Haemophilus parasuis; Serovars; Virulence evaluation; Virulence genes