Open AccessCloning and Sequencing of the Klebsiella pneumoniae O5 wb Gene Cluster and Its Role in Pathogenesis
Author(s) -
Susana Merino,
Marı́a Altarriba,
Luís Izquierdo,
María Mercedes Nogueras,
Miguel Regué,
Juan M. Tomás
Publication year - 2000
Publication title -
infection and immunity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.508
H-Index - 220
eISSN - 1070-6313
pISSN - 0019-9567
DOI - 10.1128/iai.68.5.2435-2440.2000
Subject(s) - biology , klebsiella pneumoniae , escherichia coli , gene cluster , open reading frame , cosmid , gene , antigen , mutant , clone (java method) , microbiology and biotechnology , enterobacteriaceae , recombinant dna , genetics , peptide sequence
One representative recombinant clone encodingKlebsiella pneumoniae O5-antigen lipopolysaccharide (LPS) was found upon screening for serum resistance in a cosmid-based genomic library ofK. pneumoniae KT769 (O5:K57) introduced intoEscherichia coli DH5α. A total of eight open reading frames (wb O5 gene cluster) were necessary to produceK. pneumoniae O5-antigen LPS inE. coli K-12. The enzymatic activities proposed for thewb O5 gene cluster are in agreement with the activities proposed for the biosynthesis ofK. pneumoniae O5-antigen LPS. Using the complete DNA sequence of theK. pneumoniae wb O5 gene cluster, we obtained (by single or double recombination) genetically well-characterized mutants devoid only of this O5-antigen LPS. Finally, using these O5− mutants and the corresponding wild-type strains or complemented mutants with thewb O5 gene cluster (O5+ strains), we found that the presence ofK. pneumoniae O5-antigen LPS is essential for some pathogenic features like serum resistance, adhesion to uroepithelial cells, and colonization (experimental infections) of the urinary tract in rats.