儿茶酚胺类激素对猪胸膜肺炎放线杆菌生长调控的机制研究

病原菌能主动响应宿主的儿茶酚胺类应激激素，从而调节自身的生长、代谢和毒力等行为，这种现象成为了应激能影响感染性疾病发生与发展的一种新的机制，也是病原菌重要的致病机理之一。胸膜肺炎放线杆菌(APP)是一种猪的重要呼吸道病原菌，我们的前期研究发现儿茶酚胺类激素可以调控APP大量基因的表达，并在铁限制条件下促进APP的生长。本项目拟进一步证实儿茶酚胺类激素对APP生长的调控作用，并从APP的儿茶酚胺类激素受体信号通路和铁的利用调控两个方面探索解析儿茶酚胺类激素促进APP生长的分子机制。本研究从宿主分泌的激素小分子对病原菌的作用这一视觉来研究病原菌与宿主的相互作用机制，研究结果对APP和其它病原菌引起的传染病的发病机制和新型防控策略的研究都具有重要的理论和现实意义。

Pathogenic bacteria can actively respond to host stress hormones (catecholamines), thereby regulate their growth, metabolism, virulence characters and other behaviors. This phenomenon provides new explanations of the fact that stress can influence the occurence and development of infectious disease, and is also an important aspect contributing to bacterial pathogenesis. Actinobacillus pleuropneumoniae is an important swine respiratory pathogen. In our previous study, it has been confirmed that in A. pleuropneumoniae, catecholamines can regulate a great number of genes. Furthermore, catecholamines can stimulate A. pleuropneumoniae growth under iron-restricted condition. Based on these findings, this project plans to further confirm the effect of catecholamines on A. pleuropneumoniae growth, and investigate the regulation mechanism of this effect from two aspects: the receptor mediated signalling pathway and the iron metabolism regulation. This study try to investigate the interaction mechanism between bacteria and its host from the perspective of the effects of molecules secreted by host (hormones) on bacteria. The results will has important theoretical and practical significance in the identification of mechanism and the discovery of new prevention strategy of infectious disease caused by A. pleuropneumoniae and other pathogenic bacteria.