Mutation in gyrA and parC Genes of Ciprofloxacin-resistant Isolates of Acinetobacter baumannii
- VernacularTitle:耐环丙沙星鲍氏不动杆菌的gyrA基因及parC基因突变分析
- Author:
Yan LI
;
Zhen SONG
;
Xiaohong SONG
- Publication Type:Journal Article
- Keywords:
Acinetobacter baumannii;
Resistance;
gyr A gene;
parC gene;
Quinolone
- From:
Chinese Journal of Nosocomiology
1994;0(01):-
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE To study the correlation between mutations of gyrA and parC genes and ciprofloxacin-(resistant) clinical isolates of Acinetobacter baumannii from Chengdu.METHODS The genes of gyrA and parC DNA in 28 ciprofloxacin-resistant and 2 ciprofloxacin-susceptible isolates of A.baumannii were amplified by PCR and then analyzed by restriction fragment length polymorphism(PCR-RFLP) and DNA sequencing.(RESULTS) Hinf Ⅰ digestion of the gyrA gene products of susceptible isolates(generated) two fragments,but resistant isolates(generated) one fragment.The parC gene products generated 2 fragments.DNA sequencing of 5 resistant isolates revealed mutations in gyrA gene that resulted in amino acid substitutions: Ser83→Leu and Ala88→Thr,especially,Ser83 point mutation accounting for the disappearance of sequence of Hinf Ⅰ.There was not any mutation in(gyrA) of 1 susceptible isolate;the substitution of Ser108→Ile in parC(gene) of 1 susceptible and 1 resistant isolates were identified,the remaining four isolates had more nosense mutations.CONCLUSIONS Compared with parC gene mutations,(gyrA) gene mutations of A.baumannii appears to be the main molecular mechanism responsible for ciprofloxacin resistance.The high-level ciprofloxacin resistance in A.baumannii probably needs a variety of mutations.
