title: Penicillin-binding protein 2 genes of chromosomally-mediated penicillin-resistant Neisseria gonorrhoeae from Greece: screening for codon Asp-345A.
abstract: Low affinity of penicillin for altered penicillin-binding protein 2 (PBP 2) of Neisseria gonorrhoeae that are chromosomally resistant to penicillin (CMRNG) has been attributed, at least partly to the insertion of an additional aspartic acid (Asp-35A) codon in the penA gene. Oligonucleotide probes were used to detect the presence or absence of this extra amino-acid residue in 34 non-penicillinase producing N. gonorrhoeae with decreased susceptibility to penicillin (MICs 0.25-2 mg/L) and 11 strains sensitive to penicillin (MIC < or = 0.06 mg/L) isolated in Greece and previously characterized by auxotype and serovar. The Asp-345A codon was found in all CMRNG strains as well as in strains with intermediate resistance to penicillin, but was absent from all strains exhibiting an MIC of penicillin of < or = 0.03 mg/L. No association of the Asp-345A insertion to any particular auxotype or serovar was found. These results expand the previously reported correlation between the presence of the Asp-345A codon and reduced sensitivity to penicillin, and shows that this particular mutation is common among epidemiologically distinct CMRNG strains.
authors.affiliation: Laboratory of Hygiene, Medical Faculty, Aristotle University, Thessaloniki, Greece.
authors.forename: I
authors.initials: I
authors.lastname: Tirodimos
authors.forename: E
authors.initials: E
authors.lastname: Tzelepi
authors.forename: V C
authors.initials: VC
authors.lastname: Katsougiannopoulos
mesh_terms: D000595:Amino Acid Sequence; D001224:Aspartic Acid / Q000378:metabolism; D001426:Bacterial Proteins; D001483:Base Sequence; D002352:Carrier Proteins; D002876:Chromosomes, Bacterial / Q000502:physiology*; D003062:Codon; D006115:Greece; D006602:Hexosyltransferases / Q000235:genetics*; D006801:Humans; D006824:Hybridization, Genetic; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000235:genetics*; D002267:Muramoylpentapeptide Carboxypeptidase; D009344:Neisseria gonorrhoeae / Q000201:enzymology / Q000235:genetics*; D015345:Oligonucleotide Probes; D010403:Penicillin Resistance / Q000235:genetics*; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D003062:Codon; D009097:Multienzyme Complexes; D015345:Oligonucleotide Probes; D046915:Penicillin-Binding Proteins; D001224:Aspartic Acid; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase