Sequencing and characterization of a novel serine metalloprotease from Burkholderia pseudomallei

Burkholderia pseudomallei, a Gram-negative bacterium is found in the soil a nd water, mainly in Southeast Asia and Northern Australia. It is responsibl e for melioidosis in human and animals. The bacteria produce several potent ial virulent factors such as extracellular protease, hemolysin, lipase and lecithinase. The isolation of virulence genes and the study of their functi ons will contribute to our understanding of bacterial pathogenesis. Previou s studies have implicated protease as a contributing virulence factor in th e pathogenesis of some bacteria. Three out of 5000 clones screened from a g enomic DNA library of B. pseudomallei were found to express protease activi ty. The clones were found to have the same sequence. The nucleotide sequenc e revealed an open reading frame (designated as metalloprotease A, mprA) en coding a 500-amino acid protein, MprA, with an estimated molecular mass of 50 241 Da. The predicted amino acid sequence shares homology with the subti lisin family of serine proteases. (C) 2000 Federation of European Microbiol ogical Societies. Published by Elsevier Science B.V. All rights reserved.