Constitutive expression of a chromosomal class A (BJM group 2) beta-lactamase in Xanthomonas campestris.

ABSTRACT: Sequencing of the upstream region of the beta-lactamase gene from Xanthomonas campestris pv. campestris 11 (bla(XCC-1)) revealed the cognate ampR1 gene (289 amino acids, 31 kDa). It runs divergently from bla(XCC-1) with a 100-bp intergenic region (IG) containing partially overlapped promoters with structural features typical of the bla-ampR IG. The deduced AmpR1 protein shows significant identity in amino acid sequence and conserved motifs with AmpR proteins of other species, e.g., of Pseudomonas aeruginosa (58.2% amino acid identity). Results of insertional mutation, complementation tests, and beta-lactamase assays suggested that expression of bla(XCC-1) was constitutive and dependent on AmpR1. Four bla genes and two ampR genes are present in the fully sequenced X. campestris pv. campestr

SUBMITTER: Weng SF 

PROVIDER: S-EPMC310161 | biostudies-literature | 2004 Jan

REPOSITORIES: biostudies-literature