Frey J, Cheng X, Monnerat M P, Abdo E M, Krawinkler M, Bölske G, Nicolet J
Institute for Veterinary Bacteriology, University of Berne, Switzerland.
Res Microbiol. 1998 Jan;149(1):55-64. doi: 10.1016/s0923-2508(97)83624-8.
The gene encoding a lipoprotein of 67 kDa, named P67, was cloned from Mycoplasma sp. bovine group 7 strain PG50 and expressed in Escherichia coli K12. Analysis of the amino acid sequence derived from the DNA sequence of the P67 gene revealed a typical prokaryotic signal peptidase II membrane lipoprotein lipid attachment site and a transmembrane structure domain in the leader sequence at the amino-terminal end of the protein. Protein P67 showed 91% identical amino acid residues to the lipoprotein P72 of Mycoplasma mycoides subsp. mycoides small colony type (SC) and 53% identical amino acid residues to a peptide of an unassigned gene on the genome of Mycoplasma capricolum subsp. capricolum. Antibodies made against recombinant P67 reacted with a 67-kDa protein in all Mycoplasma sp. bovine group 7 strains tested and also, to some extent, with P72 of Mycoplasma mycoides subsp. mycoides SC. The gene encoding P67 was present in all strains of Mycoplasma sp. bovine group 7 analysed, but not in other Mycoplasma sp. of the "mycoides cluster" and not in the phylogenetically related Mycoplasma putrefaciens. PCR and restriction fragment analysis revealed that the gene of P67 is conserved in all strains of Mycoplasma sp. bovine group 7. A specific PCR reaction based on the P67 gene sequence enabled rapid identification of strains belonging to Mycoplasma sp. bovine group 7.
从牛支原体7群PG50菌株中克隆出编码67 kDa脂蛋白（命名为P67）的基因，并在大肠杆菌K12中进行表达。对源自P67基因DNA序列的氨基酸序列分析显示，在该蛋白氨基末端的前导序列中存在典型的原核信号肽酶II膜脂蛋白脂质附着位点和跨膜结构域。蛋白P67与蕈状支原体丝状亚种小菌落型（SC）的脂蛋白P72有91%的相同氨基酸残基，与山羊支原体山羊亚种基因组上一个未分类基因的肽段有53%的相同氨基酸残基。针对重组P67制备的抗体与所有检测的牛支原体7群菌株中的一种67 kDa蛋白发生反应，并且在一定程度上也与蕈状支原体丝状亚种SC的P72发生反应。编码P67的基因存在于所有分析的牛支原体7群菌株中，但在“蕈状支原体簇”的其他支原体物种中不存在，在系统发育相关的腐败支原体中也不存在。PCR和限制性片段分析表明，P67基因在所有牛支原体7群菌株中是保守的。基于P67基因序列的特异性PCR反应能够快速鉴定属于牛支原体7群的菌株。
