title: Genetic characterization of the Klebsiella pneumoniae waa gene cluster, involved in core lipopolysaccharide biosynthesis.
abstract: A recombinant cosmid containing genes involved in Klebsiella pneumoniae C3 core lipopolysaccharide biosynthesis was identified by its ability to confer bacteriocin 28b resistance to Escherichia coli K-12. The recombinant cosmid contains 12 genes, the whole waa gene cluster, flanked by kbl and coaD genes, as was found in E. coli K-12. PCR amplification analysis showed that this cluster is conserved in representative K. pneumoniae strains. Partial nucleotide sequence determination showed that the same genes and gene order are found in K. pneumoniae subsp. ozaenae, for which the core chemical structure is known. Complementation analysis of known waa mutants from E. coli K-12 and/or Salmonella enterica led to the identification of genes involved in biosynthesis of the inner core backbone that are shared by these three members of the Enterobacteriaceae. K. pneumoniae orf10 mutants showed a two-log-fold reduction in a mice virulence assay and a strong decrease in capsule amount. Analysis of a constructed K. pneumoniae waaE deletion mutant suggests that the WaaE protein is involved in the transfer of the branch beta-D-Glc to the O-4 position of L-glycero-D-manno-heptose I, a feature shared by K. pneumoniae, Proteus mirabilis, and Yersinia enterocolitica.
authors.affiliation: Departamento de Microbiología y Parasitología Sanitarias, División de Ciéncias de la Salud, Facultad de Farmacia, Universidad de Barcelona, Barcelona, Spain. regue@farmacia.far.ub.es
authors.forename: M
authors.initials: M
authors.lastname: Regué
authors.forename: N
authors.initials: N
authors.lastname: Climent
authors.forename: N
authors.initials: N
authors.lastname: Abitiu
authors.forename: N
authors.initials: N
authors.lastname: Coderch
authors.forename: S
authors.initials: S
authors.lastname: Merino
authors.forename: L
authors.initials: L
authors.lastname: Izquierdo
authors.forename: M
authors.initials: M
authors.lastname: Altarriba
authors.forename: J M
authors.initials: JM
authors.lastname: Tomás
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001430:Bacteriocins / Q000378:metabolism*; D001483:Base Sequence; D015139:Blotting, Southern; D003360:Cosmids; D004591:Electrophoresis, Polyacrylamide Gel; D004755:Enterobacteriaceae / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D005816:Genetic Complementation Test; D005964:Glucosyltransferases; D007711:Klebsiella pneumoniae / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D008070:Lipopolysaccharides / Q000096:biosynthesis* / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D020161:Physical Chromosome Mapping; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D001430:Bacteriocins; D008070:Lipopolysaccharides; C076729:bss protein, bacteria; D005964:Glucosyltransferases; C430063:WaaE protein, Klebsiella pneumoniae