3个血清型鸡源大肠杆菌1型菌毛蛋白抗原位点变异分析

Analysis on Variation of Antigen Prosites of Type 1 Pili from Three Sero-type Avian Escherichia coli

采用Goldkey及DNA Star分析软件对发表的3个不同血清型的鸡大肠杆菌1型菌毛结构基因(pilA)进行同源性及抗原位点分析。结果显示,3种鸡大肠杆菌(O_1、O_(78)及O_(88))l型菌毛pilA基因相似性为91.36％～98.38％,所编码的氨基酸同源性为93.50％～97.84％;3种血清型鸡大肠杆菌(O_1、O_(78)及O_(88))1型菌毛蛋白二级结构在1～73位及150～185位氨基酸的二级结构基本相似,而111～150位氨基酸的α螺旋与β折叠的数量有所不同。菌毛蛋白亲水性、抗原性及抗原决定簇预测表明,来源于3种血清型大肠杆菌的1型菌毛蛋白在l～110位及150～184位氨基酸存在相似的二级结构及抗原位点,且不同血清型之间存在一定的共同抗原。

According to DNA sequence of type 1 pili structure gene(pilA) from three different serotype(O1 ,O78 and O88 ) avian Escherichia coli strains, homologous and prosites of pili were compared and analysed with the help of Goldkey and DNA Star programs. Similarity of pilA gene and amino acids encoded by pilA were 91. 36% ~ 98. 38% and 93. 53% ~ 97. 84% , respectively. The effects of hydrophilic property, antigenicity and epitope of three type 1 pili showed that the similar secondary structure and antigen prosites were found at amino acid position from 1 to 110 and from 150 to 184 in protein of type 1 pili from three different serotype avian Escherichia coli, there are common antigen determinants among type 1 pili from different serotype avian Escherichia coli.