鸭疫里默氏杆菌膜通透性（Imp）基因功能解析

Protein encoded by gene Imp(increased membrane permeability) from Gram-negative bacteria has some important biological functions. But there are no any researches data about the function of Imp gene in Riemerella anatipestifer (RA) till now, the pathogen can cause seriously infectious diseases in duck and many other birds. Based on the previous analysis of the complete genome sequence about the high virulence RA-CH-1 strain, we plan to study the influences of Imp on cell envelope, membrane composition and permeability, lipopolysaccharide synthetic amount and assembly, virulence, organic solvent tolerance, and antibiotic resistance by the construction of gene Imp deletion RA strain. With the results, we hope to understand the role that Imp plays on the mechanism of cell envelope biogenesis, lipopolysaccharide assembly, virulence, and organic solvent tolerance. We also plan to explain the relationship between the gene Imp with organic solvent tolerance and antibiotic resistance by organic solvent tolerance induced, antibiotic induced, construction of gene Imp expression vector and transfer into the sensitive RA strain of organic solvent and antibiotic. With above research results, we can understand the biological function better, and provide some important information for us to develop a new gene-deletion marked bacterial vaccine and new drugs. This research program has important scientific, theoretical and practice values.

革兰氏阴性菌的膜通透性（Imp）基因编码蛋白具有多种生物学功能，而感染鸭等多种禽类并致严重传染病的鸭疫里默氏杆菌(Riemerella anatipestifer，RA)，国内外对其Imp基因却缺乏相关科学数据。本研究拟在前期解析RA强毒RA-CH-1株基因组信息基础上，通过构建Imp基因缺失株，探索Imp对RA菌体被膜形成、RA菌体膜组分变化和外膜通透性、RA菌体脂多糖合成量与装配、毒力、耐药性、有机溶剂耐受性等影响，以期阐明Imp基因对RA菌体被膜形成和脂多糖装配调控机制、Imp基因与RA的毒力、RA的耐药性相关性；通过机溶剂和抗生素诱导及构建Imp基因表达载体并导入（有机溶剂、抗生素）敏感RA菌株，进一步探讨Imp基因与RA对有机溶剂、抗生素耐受性的关系。研究结果将为阐明Imp蛋白的功能以及新型基因缺失标记疫苗和针对性新型药物的研制解决关键科学数据，具有重要科学价值、理论和实际意义。

革兰氏阴性菌的膜通透性（Imp）基因编码蛋白(也叫LptD蛋白)具有多种生物学功能，而感染鸭等多种禽类并致严重传染病的鸭疫里默氏杆菌(Riemerella anatipestifer，RA)，国内外对其Imp基因却缺乏相关科学数据。本研究在前期解析RA强毒RA-CH-1株和ATCC11845株基因组信息基础上，通过构建Imp基因缺失株、干扰/过表达/缺失回补等重组株，探究Imp对RA菌体被膜形成、RA菌体膜组分变化和外膜通透性、RA菌体脂多糖合成量、毒力、耐药性、有机溶剂耐受性、对非灭活血清的抵抗力等的影响，初步阐明了Imp基因对RA菌体被膜形成和脂多糖的影响、Imp基因与RA的毒力、RA的耐药性相关性；通过机溶剂和抗生素诱导及构建Imp基因表达载体并导入（有机溶剂、抗生素）敏感RA菌株，进一步探讨Imp基因与RA对有机溶剂、抗生素耐受性的关系。还建立了基于Imp基因的PCR方法检测RA及基于Imp肽核酸探针检测血清1型RA的方法，为RA的诊断提供了新的方法和思路，具有潜在的应用价值。研究结果为阐明Imp蛋白的功能以及新型基因缺失标记疫苗和针对性新型药物的研制解决关键科学数据，为Imp的功能研究提供了可行的方法和基础材料，为RA的深入研究搭建了良好的研究平台，也为RA的诊断和防治提供理论指导，具有重要科学价值、理论和实际意义。