ABSTRACT
The interaction between prulifloxacin (PUFX) and human serum albumin (HSA) was investigated under simulated physiologic conditions with fluorescence spectra. The fluorescence quenching process of HSA may be mainly governed by a static quenching mechanism. The apparent binding constant K(b) between PUFX and HSA at different temperatures were 2.08+/-1.04, 2.74+/-0.50, and 4.98+/-1.61x10(8) l/mol. The thermodynamic parameters, with a negative value of DeltaG(0), revealed that the binding is a spontaneous process. A binding distance R of 1.19 nm between donor and acceptor was obtained from the Forster energy transfer theory.
Subject(s)
Dioxolanes/metabolism , Fluoroquinolones/metabolism , Piperazines/metabolism , Serum Albumin/metabolism , Binding Sites , Dioxolanes/chemistry , Fluoroquinolones/chemistry , Humans , Piperazines/chemistry , Protein Binding , Serum Albumin/chemistry , Spectrometry, Fluorescence , ThermodynamicsABSTRACT
The interaction between prulifloxacin, a kind of new oral taking antibiotic and pepsin, a kind of enzyme in the stomach has been investigated in vitro under a simulated physiological condition by different spectroscopic methods. The intrinsic fluorescence of pepsin was strongly quenched by prulifloxacin. This effect was rationalized in terms of a static quenching procedure. The binding parameters have been evaluated by fluorescence quenching methods. The negative value of DeltaG(0) reveals that the binding process is a spontaneous process. The binding distance R between donor (pepsin) and acceptor (prulifloxacin) was obtained according to the Förster's resonance energy transfer theory and found to be 0.95 nm. The results obtained herein will be of biological significance in pharmacology and clinical medicine.
