title: Characterization of the Citrobacter freundii phoE gene and development of C. freundii-specific oligonucleotides.
abstract: The phoE gene of Citrobacter freundii, encoding a pore-forming outer membrane protein, was cloned and its nucleotide sequence was determined. The homologies in terms of identical amino acids between the C. freundii PhoE protein and those of Escherichia coli, E. cloacae and Klebsiella pneumoniae were 90%, 86% and 84%, respectively. Two synthetic oligonucleotides, corresponding to hypervariable, cell surface-exposed regions of the protein, were tested for their specificity in polymerase chain reactions. They were specific for the species C. freundii, i.e., no reaction was detected with 35 non-C. freundii strains tested, including 17 Salmonella, two C. amalonaticus and three C. diversus strains, whereas all five C. freundii strains tested were correctly recognized.
authors.affiliation: Department of Molecular Cell Biology, University of Utrecht, Netherlands.
authors.forename: G
authors.initials: G
authors.lastname: Spierings
authors.forename: C
authors.initials: C
authors.lastname: Ockhuijsen
authors.forename: H
authors.initials: H
authors.lastname: Hofstra
authors.forename: J
authors.initials: J
authors.lastname: Tommassen
mesh_terms: D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001483:Base Sequence; D016971:Citrobacter freundii / Q000235:genetics*; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D010957:Plasmids; D018272:Porins; D015183:Restriction Mapping; D012475:Salmonella / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity
chemical_list: D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial; D015345:Oligonucleotide Probes; D018272:Porins