title: Influences of cationic, anionic, and nonionic surfactants on alkaline-induced intermediate of bovine serum albumin.
abstract: The formation of one molten globule-like intermediate of bovine serum albumin (BSA) at pH 11.2 has been established by circular dichroism (CD) spectra, fluorescence spectroscopy and 'phase diagram' approach. Three types of surfactants induced alpha-helical structure and resumed the tertiary structure of alkaline-induced BSA intermediate. The internalized tryptophans of the intermediate were exposed to a more polar environment in the presence of surfactants. Induction of both secondary and tertiary structures in alkaline-unfolded BSA was greater in the presence of 3.5 mM cetyltrimethylammonium bromide (CTAB) followed by 8.0 mM sodium dodecyl sulphate (SDS) and the least in 0.1 mM Tween-20. Maximum ANS binding was obtained in the presence of 0.1 mM Tween-20 followed by 8.0 mM SDS. The addition of 3.5 mM CTAB resulted in loss of ANS binding sites, suggesting the burial of hydrophobic patches.
authors.affiliation: State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Si Pai Lou 2#, Nanjing 210096, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Qu
authors.forename: Hua
authors.initials: H
authors.lastname: Lu
authors.forename: Shancheng
authors.initials: S
authors.lastname: Yan
authors.forename: Zuhong
authors.initials: Z
authors.lastname: Lu
mesh_terms: D000468:Alkalies / Q000494:pharmacology*; D000817:Anilino Naphthalenesulfonates / Q000378:metabolism; D000818:Animals; D000838:Anions; D002412:Cations; D002417:Cattle; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000494:pharmacology*; D002942:Circular Dichroism; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D011136:Polysorbates / Q000494:pharmacology*; D011487:Protein Conformation / Q000187:drug effects*; D011489:Protein Denaturation / Q000187:drug effects; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology*; D013050:Spectrometry, Fluorescence; D013501:Surface-Active Agents / Q000494:pharmacology*; D014364:Tryptophan / Q000378:metabolism
chemical_list: D000468:Alkalies; D000817:Anilino Naphthalenesulfonates; D000838:Anions; D002412:Cations; D002593:Cetrimonium Compounds; D011136:Polysorbates; D013501:Surface-Active Agents; D012710:Serum Albumin, Bovine; D012967:Sodium Dodecyl Sulfate; C027132:1-anilino-8-naphthalenesulfonate; D014364:Tryptophan; D000077286:Cetrimonium