胸膜肺炎放线杆菌adh基因敲除株与5b野生株的培养特性及致病性比较

The Comparison of Culture Characteristic and Pathogenicity of Actinobacillus pleuropneumoniae △adh with 5b

三聚体自转运黏附素(trimeric autotransporter adhesin,TAA)是近年来发现的参与猪胸膜肺炎放线杆菌(Actinoba-cillus pleuropneumoniae,APP)黏附宿主细胞的重要毒力因子。本研究比较了5badh基因缺失株(△adh)与5b野生株的生物学特性及其对仔猪的致病性。结果表明,在BHI液体培养基中,△adh生长速度明显高于5b野生株;△adh在液体培养基中细菌集聚性明显减弱;仔猪感染后临床症状典型,猪肺脏病理组织切片结果表明,△adh致病性弱于野生株。本研究结果证实adh在APP黏附宿主过程中发挥重要作用,为下一步探究APP致病机制奠定基础。

It was found that trimeric autotransporter adhesin（TAA） was the important virulence factor for Actinobacillus pleuropneumoniae（APP） adhere to host in the recent years.In this research,we compared the culture characteristic and the pathogenicity to piglet of △adh and 5b wild strain.The results showed that the growth rate of △adh was higher than 5b obviously;the △adh showed weaker aggregation compared with 5b in liquid culture condition;the piglet showed typical symptoms after the infection,the observation of HE showed that pathogenicity of the △adh was weaker than 5b wild strain.The result of the comparisons conformed the importance of adh in the progress of APP attacking to host and set basics in the pathogenic research of APP in the next step.