RT Journal Article
T1 Reactive Oxygen Species Production Is a Major Factor Directing the Postantibiotic Effect of Fluoroquinolones in Streptococcus pneumoniae
A1 García Esteban, María Teresa
A1 Valenzuela, Myriam Victoria
A1 Ferrándiz, María José
A1 Gonzalez de la Campa, Adela
AB We studied the molecular mechanisms involved in the postantibiotic effect of the fluoroquinolones levofloxacin and moxifloxacin in Streptococcus pneumoniae. Wild-type strain R6 had postantibiotic effects of 2.05 ± 0.10 h (mean ± standard deviation [SD]) and 3.23 ± 0.45 h at 2.5× and 10× MIC of levofloxacin, respectively. Moxifloxacin exhibited lower effects of 0.87 ± 0.1 and 2.41 ± 0.29 h at 2.5× and 10× MIC, respectively. Fluoroquinolone-induced chromosome fragmentation was measured at equivalent postantibiotic effects for levofloxacin (2.5× MIC) and moxifloxacin (10× MIC). After 2 h of drug removal, reductions were approximately 7-fold for levofloxacin and 3-fold for moxifloxacin, without further decreases at later times. Variations in reactive oxygen species production were detected after 4 to 6 h of drug withdrawals, with decreases ≥400-fold for levofloxacin and ≥800-fold for moxifloxacin at 6 h. In accordance, after 4 to 6 h of drug withdrawal, the levofloxacin-induced upregulation of the fatCDEB operon, introducing iron in the bacteria, decreased up to 2- to 3-fold, and the moxifloxacin-induced upregulation of several genes involved in the production of pyruvate was reduced 3- to 7-fold. In accordance, lower postantibiotic effects (up to 1 h) were observed in strain R6 ΔspxB, lacking the main enzyme involved in oxygen peroxide production, than in R6. Although no change in the recovery of chromosome fragmentation was observed between R6 and R6 ΔspxB, 3.5 × 103-fold lower reactive oxygen species production was observed in R6 ΔspxB, without changes after drug removal. These results show that reactive oxygen species are the main factors directing the postantibiotic effect of levofloxacin and moxifloxacin in S. pneumoniae.
PB American Society for Microbiology
SN 0066-4804
YR 2019
FD 2019-08
LK https://hdl.handle.net/20.500.14352/112442
UL https://hdl.handle.net/20.500.14352/112442
LA eng
NO García M.T., Valenzuela M.V., Ferrándiz M.J., De la Campa A.G. (2019). Reactive oxygen species production is a major factor directing the postantibiotic effect of fluoroquinolones in Streptococcus pneumoniae. Antimicrob Agents Chemother. 2019. 63 (8): e00737-19.
NO Ministerio de Economía y Competitividad (España)
DS Docta Complutense
RD 7 abr 2025