猪源鹦鹉热衣原体外膜主蛋白编码基因的克隆和序列测定

The cloning and sequence analysis of the major outer membrane protein coding gene of Chlamydia psittaci of swine origin

运用PCR技术扩增 3株猪源鹦鹉热衣原体的外膜主蛋白 (MOMP)编码基因 ,将扩增产物连接到pMD 18 T载体克隆 ,经酶切鉴定、PCR鉴定并分析其序列 ,3菌株的MOMP核苷酸序列的同源性为 98.4%～ 99.0 % ,氨基酸序列的同源性为 97.5 %～ 98.1% ,他们之间的差异很小 ,属于同一血清型。与国外发表的GPIC株及Mn株的MOMP比较 ,核苷酸序列的同源性分别为 79.5 %～ 80 .4%和 70 .9%～ 71.3 %。氨基酸序列的同源性分别为 84.2 %～ 84.7%和 80 .2 %～80 .5 %。同时发现 3菌株与GPIC株具有相似的基因可变区 。

By polymerase chain reaction (PCR) technique the gene coding the major outer membrane protein(MOMP) of three strains of Chlamydia psittaci of swine origin were amplified with a pair of special primers which were designed on the basis of the Gene Bank, and then the MOMP gene fragments were ligated into pMD 18 T vector, respectively. It was identified by restriction endonuclease and PCR. In comparisons among the three strains,the homologies of the nucleotide sequences and putative amino acid sequences are 98.4%～99.0% and 97.5%～98.1%,respectively. Their differences were very small and they may belong to same serum type .In comparisons of the three strains with GPIC and Mn strain in the Gene Bank,the homologies of nucleotide sequences are 79.5%～80.4% and 70.9%～71.3% and the identities of putative amino acid sequences are 84.2%～84.7% and 80.2%～80.5%, respectively .Through comparisons ,it was found that the three strains in our country have the same variable domains with the GPIC strain, but differs from the Mn strain a lot.