title: Stabilization of Human Serum Albumin against Urea Denaturation by Diazepam and Ketoprofen.
abstract: Stabilizing effect of diazepam and ketoprofen, Sudlow's site II markers on human serum albumin (HSA) against urea denaturation was studied using fluorescence spectroscopy. The two-step, three-state urea transition of HSA was transformed into a single-step, two-state transition with the abolishment of the intermediate state along with a shift of the transition curve towards higher urea concentrations in the presence of diazepam or ketoprofen. Interestingly, a greater shift in the transition curve of HSA was observed in the presence of ketoprofen compared to diazepam. A comparison of the intrinsic fluorescence and three-dimensional fluorescence spectra of HSA and partially-denatured HSAs, obtained in the absence and the presence of diazepam or ketoprofen suggested significant retention of native-like conformation in the partially-denatured states of HSA in the presence of Sudlow's site II markers. Taken together, all these results suggested stabilization of HSA in the presence of diazepam or ketoprofen, being greater in the presence of ketoprofen.
authors.forename: Pralad
authors.initials: P
authors.lastname: Manoharan
authors.forename: Yin H
authors.initials: YH
authors.lastname: Wong
authors.affiliation: Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. saadtayyab2004@yahoo.com.
authors.forename: Saad
authors.initials: S
authors.lastname: Tayyab
mesh_terms: D003975:Diazepam / Q000494:pharmacology*; D006801:Humans; D007660:Ketoprofen / Q000494:pharmacology*; D008024:Ligands; D011489:Protein Denaturation / Q000187:drug effects*; D055550:Protein Stability / Q000187:drug effects; D012709:Serum Albumin / Q000737:chemistry*; D014508:Urea / Q000494:pharmacology*
chemical_list: D008024:Ligands; D012709:Serum Albumin; D014508:Urea; D007660:Ketoprofen; D003975:Diazepam