GyrA mutations in ciprofloxacin-resistant clinical isolates of Pseudomonas aeruginosa in a Silesian Hospital in Poland.
Among 73 clinical isolates of Pseudomonas aeruginosa 48 strains were ciprofloxacine (CIP) susceptible and 25 CIP resistant (Minimal inhibitory concentration--MIC>32 microg/ml - 14 strains) or of intermediate susceptibility to CIP (MIC > or = 1,5 - 32 microg/ml - 11 isolates). Mutations in the quinolone-resistance-determining region (QRDR) of gyrA gene were searched in groups of CIP resistant and of intermediate susceptibility to CIP isolates. Two methods: restriction fragment length polymorphism (RFLP) analysis and DNA sequencing analysis allowed to detect three different mutations. The nucleotide substitutions observed led to the following amino acid replacements: Thr-83 --> Ile, Asp-87 --> Asn, Asp-87 --> Gly. One mutated strain among the group of mutants analyzed showed double mutation (Thr-83 --> Ile, Asp-87 --> Gly) and additional silent mutation (Val-103 --> Val); whilst the rest of the isolates showed different single missense mutations. The most frequently detected mutation in the gyrA gene (16 out of 25 mutants) was the Thr-83 --> Ile substitution.
Wydmuch
Zenobia
Z
Department of Microbiology, Medical University of Silesia, Sosnowiec, Poland.
Skowronek-Ciołek
Olga
O
Cholewa
Krzysztof
K
Mazurek
Urszula
U
Pacha
Jerzy
J
Kepa
Małgorzata
M
Idzik
Danuta
D
Wojtyczka
Robert D
RD
D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001483:Base Sequence; D002939:Ciprofloxacin / Q000494:pharmacology*; D027081:DNA Gyrase / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial / Q000235:genetics; D006801:Humans; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009154:Mutation; D011044:Poland; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011552:Pseudomonas Infections / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D016415:Sequence Alignment
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D002939:Ciprofloxacin; D027081:DNA Gyrase