Isolation And Identification Of Brucella And Cloning Of OMP25 Gene

The Brucellosis, caused by Brucella, is a kind of infectious diseases contracted commonly by both human beings and livestock ,which has been widespread for a long time in Inner Mongolia.The samples of aborted fetus and lamb as well as milk of dairy cattle whose brucellosis serological test was positive were collected to carry on the isolation and identification of pathogen.After separation,smear,biochemLcal tests and slide agglutination test,4 Brucella strains were separated and identified that 3 strains of isolates were Brucella melitensis biovar 3 and the other 1 strain was the biotype 3 of cattle species with the methods of carbon dioxide experiment,hydrogen sulfide experiment,dye inhibition,single-factor serum and phage test,such results were identical.For making up the some deficiences of serologic diagnosis and microbiological examination,At the same time,according to the Brucella outer membrane protein 25 kDa (OMP25) gene sequences reported on GeneBank to design primer in order to amplify the two biotype Brucella strains and standard strain separately by PCR technique and clon by connecting with the T vector. Sequence analysis showed that the target gene was cloned successfully and the nucleotide of Brucella melitensis biovar 3 isolates had 100% identity and had 99.8% identity with reference strains,cattle species strain has 99.5% identity with reference strains.The Cloning of OMP25 has a great importance to detect and diagnose Brucellosis.