title: Unique variations of pbp2b sequences in penicillin-nonsusceptible Streptococcus pneumoniae isolates from Korea.
abstract: pbp2b gene alterations were analyzed in 102 clinical isolates of Streptococcus pneumoniae (30 penicillin susceptible, 23 intermediate, and 49 resistant) from Korea. On the basis of PBP2B amino acid sequences, penicillin-nonsusceptible isolates of S. pneumoniae belonged to six groups, and 76% of the isolates in groups I to IV showed the same divergent block of amino acid alterations. Thirteen isolates (group II) also possessed a divergent block that was identical to that of Streptococcus oralis. The pbp2b genes of most Korean isolates showed novel mosaic mutations due to horizontal gene transfer. The Thr252 --> Ala substitution, previously thought to be associated only with penicillin-nonsusceptible strains, was also found in three penicillin-susceptible strains. On the basis of their pbp2b nucleotide sequences, all penicillin-nonsusceptible isolates can be detected by multiplex PCR, which can be used as a novel method for detection of antibiotic-resistant pneumococcal strains in clinical specimens.
authors.affiliation: Asian-Pacific Research Foundation for Infectious Diseases,, Seoul 135-710, Korea.
authors.forename: Jin Yang
authors.initials: JY
authors.lastname: Baek
authors.forename: Kwan Soo
authors.initials: KS
authors.lastname: Ko
authors.forename: Won Sup
authors.initials: WS
authors.lastname: Oh
authors.forename: Sook-In
authors.initials: SI
authors.lastname: Jung
authors.forename: Yeon Sook
authors.initials: YS
authors.lastname: Kim
authors.forename: Hyun-Ha
authors.initials: HH
authors.lastname: Chang
authors.forename: Hyuck
authors.initials: H
authors.lastname: Lee
authors.forename: Shin Woo
authors.initials: SW
authors.lastname: Kim
authors.forename: Kyong Ran
authors.initials: KR
authors.lastname: Peck
authors.forename: Nam Yong
authors.initials: NY
authors.lastname: Lee
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Song
mesh_terms: D000595:Amino Acid Sequence; D019881:Aminoacyltransferases; D001426:Bacterial Proteins / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics*; D014644:Genetic Variation; D006602:Hexosyltransferases / Q000235:genetics*; D006801:Humans; D007723:Korea; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D002267:Muramoylpentapeptide Carboxypeptidase / Q000235:genetics*; D010403:Penicillin Resistance / Q000235:genetics*; D046915:Penicillin-Binding Proteins; D010406:Penicillins / Q000494:pharmacology; D010458:Peptidyl Transferases / Q000235:genetics*; D011008:Pneumococcal Infections / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D046915:Penicillin-Binding Proteins; D010406:Penicillins; D019881:Aminoacyltransferases; C478701:penicillin-binding protein 2b, Streptococcus; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase