Open AccessFacile construction of mutations in Haemophilus ducreyi using lacZ as a counter‐selectable marker
Author(s) -
Bozue Joel A,
Tarantino Laurie,
Munson Robert S
Publication year - 1998
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1998.tb13097.x
Subject(s) - haemophilus ducreyi , mutant , virulence , selectable marker , electroporation , biology , microbiology and biotechnology , gene , plasmid , bacteria , pasteurellaceae , genetics , haemophilus influenzae
Haemophilus ducreyi is a Gram‐negative bacterium which is the causative agent of chancroid, an ulcerative sexually transmitted disease. In order to understand the pathogenesis of H. ducreyi disease, studies designed to identify potential virulence determinants and construct mutants deficient in the elaboration of these determinants have been undertaken in several laboratories. At the present time, construction of isogenic mutants is accomplished by electroporation of linearized DNA containing insertionally inactivated H. ducreyi genes followed by selection for the resistance marker encoded on the inactivated gene. In our experience, certain mutants are difficult to construct using this procedure. In the construction of strains containing lacZ as a reporter gene, we observed that the growth of lacZ expressing H. ducreyi was inhibited in the presence of X‐gal. We have exploited this observation to develop a new strategy for the construction of isogenic H. ducreyi mutants.