猪胸膜肺炎放线杆菌Apx毒素的分子生物学与致病机理  

Molecular Biology and Pathogenesis of APX toxins of Actinobacillus Pleuropneumoniae

作　　者：胡成名[1] 文心田[1] 曹三杰[1] 黄小波[1] 

机构地区：[1]四川农业大学动科院动物传染病与基因芯片实验室动物疫病与人类健康四川省重点实验室,四川雅安625014

出　　处：《动物医学进展》2007年第7期94-98,共5页Progress In Veterinary Medicine

摘　　要：猪传染性胸膜肺炎是由胸膜肺炎放线杆菌（App）引起的猪的一种呼吸道传染病。到目前为止,APP已经被分离鉴定出了15种血清型（1~15）。15种血清型的APP能产生属于RTX毒素家族的4种Apx毒素,分别为ApxⅠ、ApxⅡ、ApxⅢ和ApxⅣ。ApxⅠ操纵子包含有ApxⅠC、A、B、D 4个基因;ApxⅠ毒素含有13个富含甘氨酸的重复区。ApxⅡ操纵子仅包括结构基因ApxⅡA和激活基因ApxⅡC,而无分泌基因;ApxⅡ蛋白含有8个甘氨酸的序列重复。ApxⅢ操纵子与ApxⅠ操纵子相同,具有一个完整的操纵子;ApxⅢ在N-末端有3个疏水区,在C末端部分有13个富含甘氨酸的区域。Apx毒素的致病机理为先由没有活性的前体蛋白转变为有活性的ApxA蛋白,再由有活性的ApxA蛋白侵害细胞。Actinobacillus pleuropneumoniae （App） is the pathogen of porcine pleuropneumonia, a severe, contagious pulmonary disease of pigs that causes great economic losses in industrialized pig production. So far, App has been identified for 15 serotypes according to serological typing of capsular polysaccharides; serotype 5 is subdivided further into 5a and 5b. Actinobacillus pleuropneumoniae produces four different RTX toxins, which are called Apx toxins （for A. pleuropneumoniae RTX toxins）： Apx Ⅰ , Apx Ⅱ , Apx Ⅲ, ApxⅣ respectively. Apx Ⅰ operon contains gene Apx Ⅰ C,A,B and D; Apx I toxin contains 13 glycinerich areas. Apx Ⅱ operon includes only structure gene Apx A and activation gene Apx C; Apx Ⅱ protein contains 8 glycine sequence repeat. Like Apx I operon, ApxⅢ operon contains all the elements of a operon; ApxⅢ has 3 hydrophobic area in the N-terminal, 13 glycine-rich region in the C-terminal part. Pathogenesis of Apx toxins： firstly, precursor protein changed into the active protein Apx A,then the Apx A do disoperation against ceils.

关 键 词：胸膜肺炎放线杆菌 APX毒素 分子生物学 致病机理 

分 类 号：S852.619[农业科学—基础兽医学] S858.28[农业科学—兽医学]