title: Guanidinium chloride-induced spectral perturbations of 4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid confound interpretation of data on molten globule states.
abstract: We describe limitations in the use of 4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid (bis-ANS) to examine unfolding intermediates associated with guanidinium chloride (GuHCl)-induced protein denaturation. Several studies have used alterations in fluorescence emission of bis-ANS to quantify the population of "molten globule" states. Our findings indicate that the observed changes in bis-ANS spectroscopic properties could originate from the interactions of bis-ANS and GuHCl and the aggregation of the dye at higher GuHCl concentrations. We posit that in the absence of additional complementary structural or spectroscopic measurements, the use of bis-ANS emission alone to monitor protein conformations can be misleading.
authors.affiliation: Section of Endocrinology, Diabetes, and Nutrition, Boston University School of Medicine, Boston, MA 02118, USA.
authors.forename: M N
authors.initials: MN
authors.lastname: Zakharov
authors.forename: J
authors.initials: J
authors.lastname: Ulloor
authors.forename: S
authors.initials: S
authors.lastname: Bhasin
authors.forename: J A
authors.initials: JA
authors.lastname: Ross
authors.forename: N S
authors.initials: NS
authors.lastname: Narula
authors.forename: M
authors.initials: M
authors.lastname: Bakhit
authors.forename: B K
authors.initials: BK
authors.lastname: Pillai
authors.forename: R
authors.initials: R
authors.lastname: Kumar
authors.forename: D M
authors.initials: DM
authors.lastname: Jameson
authors.forename: R
authors.initials: R
authors.lastname: Jasuja
mesh_terms: D000817:Anilino Naphthalenesulfonates / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D019791:Guanidine / Q000032:analysis / Q000494:pharmacology*; D011487:Protein Conformation / Q000187:drug effects; D011489:Protein Denaturation / Q000187:drug effects; D058767:Protein Unfolding / Q000187:drug effects; D011506:Proteins / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013329:Structure-Activity Relationship
chemical_list: D000817:Anilino Naphthalenesulfonates; D011506:Proteins; C035763:5,5'-bis(8-(phenylamino)-1-naphthalenesulfonate); D019791:Guanidine