Homology and Phylogenetic Analysis of Nucleotide Sequence of Omp2a Gene of Brucella abortus Local Isolates

The objective of this research was to determine the homology level and phylogenetic relationship of nucleotide sequence of omp2a gene fragment of local isolates Brucella abortus compared to B. abortus isolates from foreign countries that were accessed in GenBank. B. abortus were isolated from infected cattle from South Sulawesi and East Nusa Tenggara which obtained from Disease Investigation Center Maros. Omp2a gene of B. abortus local isolates were amplified by Polymerase Chain Reaction (PCR) technique. Specifically-designed primers used in PCR were 2ab5F and 2a900R (Sifuentes-Rincon, 1997). PCR product were sequenced by Abi Prism 310 Genetic Analyser-Applied Biosystems to get the omp2a gene nucleotide data. Then this nucleotide sequence were analyzed for homology level to isolates from foreign countries by using BLAST. The result showed that the homology level between omp2a gene nucleotide sequence of B. abortus local isolates and isolates from foreign countries have a high homology level (99%-100%). Phylogenetic analysis were done using the multiple nucleotide sequence among B. abortus isolates alignment program of BioEdit. The analysis showed that B.abortus isolate from South Sulawesi has closely related to isolates from India and France, whereas B. abortus isolate from East Nusa Tenggara has closely related to isolate from South Sulawesi and India.