禽致病性大肠杆菌唾液酸酶siaK1基因缺失株的构建及其生物学特性分析

Construction of the siaK1 mutant of avian pathogenic Escherichia coli and its characterization

禽致病性大肠杆菌(avian pathogenic Escherichia coli,APEC)是危害养禽业发展的重要病原之一。本试验利用Red同源重组技术构建APEC IMT5155唾液酸酶基因sia K1缺失株和互补株,系统比较其生物学特性的差异。生长曲线测定表明,缺失株比野生株和互补株生长速度加快,而野生株和互补株的生长速度无明显差异;生物被膜形成能力测定表明,sia K1缺失导致细菌生物被膜形成能力显著减弱,而互补株可恢复至野生株水平,说明sia K1基因缺失可影响禽致病性大肠杆菌的生长速度及生物被膜的形成。本研究为进一步探讨sia K1基因功能奠定了基础。

Avian pathogenic Escherichia coli （APEC） is one of the most important bacterial pathogens in the poultry industry. To character- ize the sialidase gene siaK1 in APEC, the siaKl mutant of APEC was constructed by the Red recombination system. Then the differences of growth and biofilm formation were analyzed between the siaK1 mutant strain and the wild strain. Compared with the wild strain, the mutant strain had significant difference in growth. The growth curves indicated that siaKl mutant grew more quickly compared to that of wild strain. However, biofilm formation significantly decreased. These data indicated that siaK1 gene could influence the growth and biofilm formation of APEC. This study provides a basis for investigation of the function of siaK1 gene in APEC.