Typing on the cellular fatty acids of Brucella species by Gas-chromatography analysis / 中国人兽共患病学报

ABSTRACT

To investigate the the possibility to utilize the cellular fatty acid (CFA) information as a method in Brucella typing, 90 Brucella strains were subjected to the study on CFAs, and all the experimental strains were inoculated on Brucella Agar plates for 48 hours. After that, cells were harvested, saponificated, methylated and extracted to provide fatty acids methylesters for gas chromatography analysis. Based on the CFAs data matrix, dendrogram of 90 experimental strains was generated by SPSS11.5 software package. As shown in the dendrogram, 90 Brucella strains could be divided into 5 clusters. The first cluster included some species of Brucella abortus,Brucella melitensis,Brucella suis, Brucella ovis; and some of the variant strains of Brucella abortus and Brucella melitensis and the typical strain of Brucella neotomae. The second cluster included typical strains of Brucella suis (1,2,3 and 5 types); vaccine strains of Brucella suis S2; vaccine strains of Brucella melitensis M28、Rev.1 and typical strain of Brucella ovis. The third cluster included some of Brucella melitensis; some of the variant strains of Brucella melitensis; some of Brucella abortus(3,6 types); Brucella canis and Brucella ovis. The fourth cluster was the typical strain of Brucella canis.and the fifth cluster included some of Brucella melitensis(1 type); some of Brucella abortus (1 type); some of the variant strains of Brucella melitensis and Brucella suis(1,3 type). It is apparent that CFAs information can be used in brucella typing. and Brucella suis and Brucella canis can be distinguished by the difference in the CFA contents of 3 fatty acids 190CYCLOω8c, 181ω7c and 160. The results of CFAs typing in Brucella species show that Brucella canis includes 2 biovars at least and the high homologization of Brucella abortus (3 type) and Brucella abortus(6 type) can be found.