Gene Disruption by Homologous Recombination in the Xylella fastidiosa Citrus Variegated Chlorosis Strain

Abstract

Mutagenesis by homologous recombination was evaluated in Xylella fastidiosa by using the bga gene, coding for beta-galactosidase, as a model. Integration of replicative plasmids by homologous recombination between the cloned truncated copy of bga and the endogenous gene was produced by one or two crossover events leading to beta-galactosidase mutants. A promoterless chloramphenicol acetyltransferase gene was used to monitor the expression of the target gene and to select a cvaB mutant.