[Characteristics of Yersinia enterocolitica genes isolated in Ningxia Hui autonomous region from 1997 to 2010].
OBJECTIVE
To investigate the distribution of virulent genes of Yersinia enterocolitica (Y. enterocolitica) in Ningxia Hui autonomous region and the characteristics of the molecular patterns of Y. enterocolitica.


METHODS
283 strains of Y. enterocolitica were isolated in Ningxia Hui autonomous region between year 1997 and 2010. The genes ail, ystA, ystB, yadA and virF were analyzed by PCR method; the chromosomal DNA of Y. enterocolitica was digested by restriction endonucleases NotI and processed by pulsed-field gel electrophoreses (PFGE); and then the cluster analysis were conducted by BioNumeric computer software towards the above results.


RESULTS
Of all, 209 strains of serotypes O:3 and O:9 Y.enterocolitica showed positive virulence of genes ail, ystA, yadA and virF; 97.6% (204/209) of which, the ystB virulence were negative. The virulence of all genes in serotype O:8 and serum-unclassified strains were negative. 9 out of 11 strains of serotype O:5 Y. enterocolitica showed negative virulence of the above five genes. By PFGE, according to the NotI Macrorestriction Map on chromosomal DNA, the 29 strains of serotype O:3 Y. enterocolitica were divided into 12 PFGE patterns, 2 of which were dominant patterns which could be found in over 5 strains; and the 180 strains of serotype O:9 Y. enterocolitica were divided into 13 patterns, 4 of which were dominant patterns which existed in over 10 strains; which were isolated individually from pigs and house mouse, pigs and dogs as well as pigs and wild rabbits.


CONCLUSIONS
Y.enterocolitica serotypes O:3 and O:9 were pathogenic in Ningxia, and serotype O:3 becomes predominant gradually. O:5, O:8 and serum-unclassified serotypes were non-pathogenic.
Bacteriology Laboratory, Ningxia Center For Disease Control and Prevention, Yinchuan 750004, China.
Qiong
Q
Hao
Xiang
X
Liu
Bang-cheng
BC
Guo
Li-qun
LQ
Yan
Ming-ying
MY
Xie
Dong
D
Jin
Xin
X
Wang
Zhi-gang
ZG
Cui
Huai-qi
HQ
Jing
D000818:Animals; D001427:Bacterial Toxins / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004285:Dogs; D016521:Electrophoresis, Gel, Pulsed-Field / Q000379:methods; D005798:Genes, Bacterial; D051379:Mice; D011817:Rabbits; D034421:Sus scrofa; D014774:Virulence; D015009:Yersinia Infections / Q000382:microbiology; D015008:Yersinia enterocolitica / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity*
D001427:Bacterial Toxins; D004269:DNA, Bacterial