Molecular characteristics of penicillin-binding protein 2b, 2x, and 1a sequences in penicillin-nonsusceptible Streptococcus pneumoniae isolates in Shenyang, China.
The aim of this study was to investigate the nature of the amino acid motifs found in penicillin-binding proteins (PBP) 2b, 2x, and 1a of penicillin-nonsusceptible Streptococcus pneumoniae isolates from Shenyang, China, and to obtain information regarding the prevalence of alterations within the motifs or in positions flanking the motifs. For 18 clinical isolates comprising 4 penicillin-susceptible S. pneumoniae, 5 penicillin-intermediate S. pneumoniae, and 9 penicillin-resistant S. pneumoniae. the DNA sequences of PBP2b, PBP2x, and PBP1a transpeptidase domains were determined and then genotyped by multilocus sequence typing. Sequence analysis revealed that most penicillin-nonsusceptible S. pneumoniae isolates (penicillin MIC > or = 1.5 microg/mL and cefotaxime MIC > or = 2 microg/mL) shared identical PBP2b, PBP2x, and PBP1a amino acid profiles. Most penicillin-resistant S. pneumoniae isolates were ST320 (4-16-19-15-6-20-1), the double-locus variant of the Taiwan19F-14 clone. This study will serve as a basis for future monitoring of genetic changes associated with the emergence and spread of beta-lactam resistance in Shenyang, China.
Division of Infectious Diseases, The First Affiliated Hospital, China Medical University, Shenyang, Liaoning, China.
Su Fei
SF
Tian
Yun Zhuo
YZ
Chu
Bai Yi
BY
Chen
D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D002648:Child; D002681:China; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D010403:Penicillin Resistance; D046915:Penicillin-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011008:Pneumococcal Infections / Q000382:microbiology*; D016415:Sequence Alignment; D013296:Streptococcus pneumoniae / Q000737:chemistry / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism
D046915:Penicillin-Binding Proteins