Blanchard B, Saillard C, Kobisch M, Bové J M
CNEVA Ploufragan, Station de Pathologie, France.
Microbiology (Reading). 1996 Jul;142 ( Pt 7):1855-62. doi: 10.1099/13500872-142-7-1855.
A previously described DNA probe specific for Mycoplasma hyopneumoniae (I-141) was fully sequenced and found to consist of 1618 bp and to contain two tandemly repeated ORFs. The deduced amino acid sequence of the two ORFs showed significant homologies with ATP-binding cassette (ABC) transporter proteins, particularly those of the eukaryotic multidrug resistance (MDR) protein family (up to 21% identity and 47% similarity). A somewhat lower homology was evident with the secretion protein HlyB of the RTX-haemolysin from Escherichia coli. The location of the two ORFs on the M. hyopneumoniae chromosome was downstream of the rrl gene encoding the 23S rRNA, but transcribed in the opposite direction. PCR amplification and subsequent chromosomal analysis by Southern blot hybridization of several M. hyopneumoniae strains showed that all field strains contained the two putative ABC transporter genes. However, some culture collection strains derived from strain J had lost these genes as the result of a 2221 bp deletion.
一种先前描述的针对猪肺炎支原体（I-141）的DNA探针经过了全序列测定，发现其由1618个碱基对组成，并且包含两个串联重复的开放阅读框（ORF）。这两个开放阅读框推导的氨基酸序列与ATP结合盒（ABC）转运蛋白具有显著同源性，特别是与真核多药耐药（MDR）蛋白家族的转运蛋白（同一性高达21%，相似性达47%）。与大肠杆菌RTX溶血素的分泌蛋白HlyB的同源性略低。这两个开放阅读框在猪肺炎支原体染色体上的位置位于编码23S rRNA的rrl基因下游，但转录方向相反。对几株猪肺炎支原体菌株进行PCR扩增及随后的Southern印迹杂交染色体分析表明，所有田间菌株都含有这两个假定的ABC转运蛋白基因。然而，一些源自J株的保藏菌株由于2221个碱基对的缺失而丢失了这些基因。
