[ALL 98 strains of Brucella OMP25 gene is conservative in China].

OBJECTIVE

To investigate the genetic polymorphism of OMP25 gene isolated from 116 Brucella strains, including 18 Brucella reference strains and 98 Chinese field strains.

METHODS

Chromosomal DNA of Brucella strains were analyzed by PCR, and then the product OMP25 gene was digested with Hind III and separated on 10% polypropylene agarose gel electrophoresis. OMP25 genes of different types were sequenced.

RESULTS

Eight gene types (I-VIII) existing in 116 strains were examined, among them type II and VII were only found in certain wild strains. Sequencing analysis of OMP25 revealed only 10 sites varied in all 8 types. OMP25 of 98 Chinese Brucella strains was highly homologic and characteristic of stable antigen.

CONCLUSION

High conservation characteristics helps to epidemiologically detect Brucella in China as well as to found a theoretical basis for vaccine development.