Comparative analysis of genetic variations of pgm locus and its flanking regions in Yersinia pestis
- VernacularTitle:鼠疫耶尔森菌pgm位点及其侧翼序列遗传变异的比较分析
- Author:
Zongzhong TONG
;
Dongsheng ZHOU
;
Yajun SONG
- Publication Type:Journal Article
- Keywords:
Yersinia pestis;
pgm locus;
genetic variation
- From:
Medical Journal of Chinese People's Liberation Army
1981;0(04):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study genetic variations of pgm locus and its flanking regions in Yersinia pestis isolated from Chinese natural focus so as to understand differences in virulence between different strains and to improve the prevention of plague. Methods We analysed the sequence variations of pgm locus and its flanking regions by using PCR-sequencing and allele-specific PCR among 260 strains of Y. pestis isolated from different foci and 7 strains of Yersinia pseudotuberculosis. Results For YP1666, only the strains of Xilin Gol grassland type and Microtus fuscus type had intact transmembrane helix, and the T-deletion at base 1406 was unique in strains of Orientalis. Same as Y. pseudotuberculosis, there was no IS100-insertion at the 3′ end of pgm locus of strains from Eastern section of North Tianshan Mountain type, Western section of North Tianshan Mountain type A and B, Xilin Gol grassland type and M. fuscus type. Only the strains of Xilin Gol grassland type and M. fuscus type had IS285-insertion in pigmentation segment and IS100-insertion at its downstream flanking region. pgm locus was deleted entirely from 36 strains, most of which came from Ordos plateau type, Song-liao plain type B , Kunlun Mountain type A and B. Conclusion Strains of Eastern section of North Tianshan Mountain type, Western section of North Tianshan Mountain type A and B, Xilin Gol grassland type and M. fuscus type are the oldest lineage of Chinese isolates. The pgm locus of the strains of these three types is very stable because there is no IS100-insertion at its 3′ terminal. We suggest that the strains of Xilin Gol grassland type and M. fuscus type should be grouped into a fourth biovar: Microtus. pgm locus is highly conserved among strains of different ecotypes, and its variations are well correlated with biovar, focus and ecotype, which indicates that pgm locus has played a role in strains′ adaptation to their environment.
