Fluoroquinolone resistance is a poor surrogate marker for type II topoisomerase mutations in clinical isolates of Streptococcus pneumoniae.
The association between fluoroquinolone susceptibility and DNA mutations coding for amino acid substitutions in the quinolone resistance-determining region was assessed with 44 clinical isolates of Streptococcus pneumoniae. Twenty-three strains bore at least one amino acid substitution. Only seven strains with mutations were suggested by diminished susceptibility to ciprofloxacin (MIC, > or =2 microg/ml).
Millichap
J J
JJ
Departments of Pathology and Medicine, Northwestern University Medical School, Chicago, Illinois 60611, USA.
Pestova
E
E
Siddiqui
F
F
Noskin
G A
GA
Peterson
L R
LR
D019943:Amino Acid Substitution; D000890:Anti-Infective Agents / Q000494:pharmacology*; D004250:DNA Topoisomerases, Type II / Q000235:genetics*; D004352:Drug Resistance, Microbial / Q000235:genetics; D024841:Fluoroquinolones; D005819:Genetic Markers; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D009154:Mutation; D011008:Pneumococcal Infections / Q000382:microbiology; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D005819:Genetic Markers; D004250:DNA Topoisomerases, Type II