title: Comparison of the sequences of the nagE operons from Klebsiella pneumoniae and Escherichia coli K12: enhanced variability of the enzyme IIN-acetylglucosamine in regions connecting functional domains.
abstract: The nagE operon, encoding the enzyme II specific for N-acetylglucosamine (EIINag), and adjacent DNA from the chromosome of Klebsiella pneumoniae were sequenced and compared with the corresponding sequence from Escherichia coli K12. The deduced EIINag sequences differ in 72 out of 651 amino acids, the K. pneumoniae sequence being three residues longer. The amino acid differences were distributed unevenly, and were most frequent in regions connecting the three functional domains of the protein. In the nagE-nagB intergenic region, two promoter, two operator, and one CAP consensus sequence with regulatory functions were highly conserved. The nag structural genes from both species were very similar (83% DNA similarity; 89% amino acid similarity) except for frequent AT to GC exchanges in the wobble base of codons in K. pneumoniae DNA relative to the E. coli DNA.
authors.affiliation: Yale University, Dept. of Molecular Biophysics and Biochemistry, New Haven, Connecticut 06511.
authors.forename: A P
authors.initials: AP
authors.lastname: Vogler
authors.forename: J W
authors.initials: JW
authors.lastname: Lengeler
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003062:Codon; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005798:Genes, Bacterial; D007711:Klebsiella pneumoniae / Q000201:enzymology / Q000235:genetics*; D008969:Molecular Sequence Data; D009876:Operon; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid
chemical_list: D003062:Codon; D004269:DNA, Bacterial; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C055931:phosphoenolpyruvate-N-acetylglucosamine phosphotransferase