An extracellular zinc metalloprotease gene of Burkholderia cepacia

Abstract

Burkholderia cepaciaproduces at least one extracellular zinc metalloprotease that may be involved in virulence. AB. cepaciazinc metalloprotease gene was cloned using aBurkholderia pseudomalleizinc metalloprotease gene as a probe. The predicted amino acid sequences of theseB. cepaciaand aB. pseudomalleiextracellular zinc metalloproteases indicate that they are similar to the thermolysin-like family of metalloproteases (M4 family of metalloendopeptidases) and they are likely to be secreted via the general secretory pathway.zmpAisogenic mutants were constructed inB. cepaciagenomovar III strains Pc715j and K56-2 by insertional inactivation of thezmpAgenes. ThezmpAmutants produced less protease than the parent strains. TheB. cepaciastrain K56-2zmpAmutant was significantly less virulent than its parent strain in a chronic respiratory infection model; however, there was no difference between the virulence ofB. cepaciastrain Pc715j and a Pc715jzmpAmutant. The results indicate that this extracellular zinc metalloprotease may play a greater role in virulence in some strains ofB. cepacia.