[Study on the relation between the absence of one IS100 in 102 kb pgm locus of Yersinia pestis and the stability of pigmentation phenotype].

ABSTRACT

OBJECTIVE: To study the relation between the absence of one IS100 in the 102 kb pgm locus of Yersinia pestis and the stability of pigmentation phenotype (pgm(+)). METHODS: We amplified the segment including IS100 in 102 kb pgm locus of Yersinia pestis that isolated from all ecotypes in China by polymerase chain reaction (PCR). There were 171 strains isolated from 18 ecotypes in this study. One strain was chosen to be cloned and sequenced. RESULTS: Besides the type of Microtus brandti, the types of East-North Tianshan, A and B of West-North Tianshan, Microtus Qinghai had one band with about 2560 bp. These strains lost one IS100 in 102 kb pgm locus of Yersinia pestis. Their pgm(+) phenotype was stable. Some strains of ecotypes from Qilian Mountain, Qinghai-Tibet Plateau, Gangdisi Mountain, West Yunnan Mountain had no bands in the PCR products. Negative strains would lose the whole 102 kb pgm locus. The others had one band with 4492 bp. These strains had two IS100 which flanked the 102 kb pgm locus but the pgm(+) phenotype was unstable. CONCLUSION: Yersinia pestis which had only one IS100 would flank the 102 kb pgm locus and had stable pgm(+) phenotype while the Yersinia pestis that having two IS100 flanked the 102 kb pgm locus would have unstable pgm(+) phenotype.