First Streptococcus agalactiae isolates highly resistant to quinolones, with point mutations in gyrA and parC.
Three isolates of Streptococcus agalactiae highly resistant to multiple fluoroquinolones were isolated in Japan. Compared with susceptible strains of S. agalactiae, these quinolone-resistant strains had double point mutations within the quinolone resistance-determining regions of gyrA and parC; Ser-81 was changed to Leu (TCA --> TTA) in the amino acid sequence deduced from gyrA, and Ser-79 was changed to Phe (TCC --> TTC) in the amino acid sequence deduced from parC. Comparative sequence analysis revealed the possibility of gene transfer between S. agalactiae and another beta-hemolytic streptococcus, Streptococcus difficile.
Kawamura
Yoshiaki
Y
Department of Microbial-Bioinformatics, Regeneration and Advanced Medical Science, Gifu University Graduate School of Medicine, Gifu 500-8705, Japan. kawamura@cc.gifu-u.ac.jp
Fujiwara
Hiromitsu
H
Mishima
Noriko
N
Tanaka
Yuko
Y
Tanimoto
Ayako
A
Ikawa
Shiro
S
Itoh
Youko
Y
Ezaki
Takayuki
T
D000368:Aged; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000890:Anti-Infective Agents / Q000494:pharmacology*; D027081:DNA Gyrase / Q000235:genetics*; D027101:DNA Topoisomerase IV / Q000235:genetics*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D005260:Female; D022761:Gene Transfer, Horizontal; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008969:Molecular Sequence Data; D017354:Point Mutation / Q000235:genetics*; D015363:Quinolones / Q000494:pharmacology*; D013290:Streptococcal Infections / Q000382:microbiology; D013292:Streptococcus agalactiae / Q000187:drug effects* / Q000235:genetics*
D000890:Anti-Infective Agents; D015363:Quinolones; D027101:DNA Topoisomerase IV; D027081:DNA Gyrase