groEL encodes a highly antigenic protein in Burkholderia pseudomallei

No recombinant protein is available for serodiagnosis of melioidosis, In th is study, we report the cloning of the groEL gene, which encodes an immunog enic protein of Burkholderia pseudomallei, Bidirectional DNA sequencing of groEL revealed that the gene contained a single open reading frame encoding 546 amino acid residues with a predicted molecular mass of 57.1 M)a. Basic Local Alignment Search Tool analysis showed that the putative protein enco ded by groEL is homologous to the chaperonins encoded by the groEL genes of other bacteria. It has 98% amino acid identity with the GroEL of Burkholde ria cepacia, 98% amino acid identity with the GroEL of Burkholderia vietnam iensis, and 82% amino acid identity with the GroEL of Bordetella pertussis, Furthermore, it was observed that patients with melioidosis develop a stro ng antibody response against GroEL, suggesting that the recombinant protein and its monoclonal antibody may be useful for serodiagnosis in patients wi th melioidosis and that the protein may represent a good cell surface targe t for host humoral immunity. Further studies in these directions would be w arranted.