Previous Article | Next Article ![]()
Antimicrobial Agents and Chemotherapy, September 1998, p. 2304-2311, Vol. 42, No. 9
Laboratoire de Bactériologie,
Received 3 November 1997/Returned for modification 23 January
1998/Accepted 24 March 1998
Mycoplasma hominis mutants were selected stepwise for
resistance to ofloxacin and sparfloxacin, and their gyrA,
gyrB, parC, and parE quinolone
resistance-determining regions were characterized. For ofloxacin, four
rounds of selection yielded six first-, six second-, five third-, and
two fourth-step mutants. The first-step mutants harbored a single
Asp426
0066-4804/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.
Alterations in Topoisomerase IV and DNA Gyrase in
Quinolone-Resistant Mutants of Mycoplasma hominis Obtained
In Vitro
Asn substitution in ParE. GyrA changes (Ser83
Leu or Trp)
were found only from the third round of selection. With sparfloxacin,
three rounds of selection generated 4 first-, 7 second-, and 10 third-step mutants. In contrast to ofloxacin resistance, GyrA mutations
(Ser83
Leu or Ser84
Trp) were detected in the first-step mutants
prior to ParC changes (Glu84
Lys), which appeared only after the
second round of selection. Further analysis of eight multistep-selected
mutants of M. hominis that were previously described
(2) revealed that they carried mutations in ParE
(Asp426
Asn), GyrA (Ser83
Leu) and ParE (Asp426
Asn), GyrA
(Ser83
Leu) and ParC (Ser80
Ile), or ParC (Ser80
Ile) alone, depending on the fluoroquinolone used for selection, i.e.,
ciprofloxacin, norfloxacin, ofloxacin, or pefloxacin, respectively.
These data indicate that in M. hominis DNA gyrase is the
primary target of sparfloxacin whereas topoisomerase IV is the primary
target of pefloxacin, ofloxacin, and ciprofloxacin.
*
Corresponding author. Mailing address: Laboratoire de
Bactériologie, Université Bordeaux 2, 146 rue Léo
Saignat, 33076 Bordeaux cedex, France. Phone: (33) 5.57.57.16.25. Fax:
(33) 5.56.79.56.11. E-mail:
cecile.bebear{at}labbebear.u-bordeaux2.fr.
Antimicrobial Agents and Chemotherapy, September 1998, p. 2304-2311, Vol. 42, No. 9
0066-4804/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
| Clin. Vaccine Immunol. | Clin. Microbiol. Rev. |
|---|---|
| J. Clin. Microbiol. | ALL ASM JOURNALS |