A Unique Arabinose 5-Phosphate Isomerase Found within a Genomic Island Associated with the Uropathogenicity of Escherichia coli CFT073

• DOI: 10.1128/jb.00033-11
• Publication Date: 2011-04-16T07:31:37Z
• Authors: Joshua A. Mosberg; Alejandra Yep; Timothy C. Meredith; Sara Smith; Pan-Fen Wang; Tod P. Holler; Harry L. T. Mobley; Ronald W. Woodard
• Keywords: 0303 health sciences; Genomic Islands; Escherichia coli Proteins; Molecular Sequence Data; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; 3. Good health; Mice; 03 medical and health sciences; Cystitis; Mutation; Escherichia coli; Animals; Uropathogenic Escherichia coli; Kidney Diseases; Amino Acid Sequence; Aldose-Ketose Isomerases; Escherichia coli Infections

ABSTRACT

Previous studies showed that deletion of genes c3405 to c3410 from PAI- metV , a genomic island from Escherichia coli CFT073, results in a strain that fails to compete with wild-type CFT073 after a transurethral cochallenge in mice and is deficient in the ability to independently colonize the mouse kidney. Our analysis of c3405 to c3410 suggests that these genes constitute an operon with a role in the internalization and utilization of an unknown carbohydrate. This operon is not found in E. coli K-12 but is present in a small number of pathogenic E. coli and Shigella boydii strains. One of the genes, c3406, encodes a protein with significant homology to the sugar isomerase domain of arabinose 5-phosphate isomerases but lacking the tandem cystathionine beta-synthase domains found in the other arabinose 5-phosphate isomerases of E. coli . We prepared recombinant c3406 protein, found it to possess arabinose 5-phosphate isomerase activity, and characterized this activity in detail. We also constructed a c3406 deletion mutant of E. coli CFT073 and demonstrated that this deletion mutant was still able to compete with wild-type CFT073 in a transurethral cochallenge in mice and could colonize the mouse kidney. These results demonstrate that the presence of c3406 is not essential for a pathogenic phenotype.