title: Analysis of mutations in the pbp genes of penicillin-non-susceptible pneumococci from Turkey.
abstract: Sequence analysis of the pbp genes from 20 Streptococcus pneumoniae isolates from Turkey (eight with high-level penicillin-resistance, nine with low-level penicillin-resistance, and three that were penicillin-susceptible) was performed and phylogenetic trees were constructed. Most isolates clustered together within a single branch that was distinct from sequences deposited previously in GenBank, which suggests that these isolates have probably evolved following new recombination events. The most prominent active-site mutations, which have also been associated previously with resistance, were T371A in PBP1a, E481G followed by T451A in PBP2b, and T338A in PBP2x. All isolates also possessed a (570)SVES/TK(574) block in the PBP2b sequence, instead of the QLQPT sequence of R6, which is fairly uncommon in GenBank sequences. This is the first study to analyse alterations in the pbp sequences of pneumococci isolated in Turkey.
authors.affiliation: Department of Microbiology and Clinical Microbiology, Dokuz Eylul University, School of Medicine, Inciralti, Izmir, Turkey.
authors.forename: M
authors.initials: M
authors.lastname: Biçmen
authors.forename: Z
authors.initials: Z
authors.lastname: Gülay
authors.forename: S V
authors.initials: SV
authors.lastname: Ramaswamy
authors.forename: D M
authors.initials: DM
authors.lastname: Musher
authors.forename: D
authors.initials: D
authors.lastname: Gür
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D001665:Binding Sites / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D019143:Evolution, Molecular; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D010403:Penicillin Resistance / Q000235:genetics*; D046915:Penicillin-Binding Proteins / Q000235:genetics*; D010802:Phylogeny; D011008:Pneumococcal Infections / Q000382:microbiology; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013296:Streptococcus pneumoniae / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D014421:Turkey
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D046915:Penicillin-Binding Proteins