title: At very low concentrations known chaotropes act as kosmotropes for the N and B isoforms of human serum albumin.
abstract: Very few studies have been done to understand the effect of millimolar concentrations of chaotropes on protein structure. In our previous study we observed that the secondary and tertiary structure of human serum albumin (HSA) increases in the presence of 5 mmol/L urea. Micelle formation in amphoteric detergents increases in the presence of equivalent concentrations of urea. Here, we observed a significant increase in the secondary and tertiary structure of HSA. Interestingly, guanidine hydrochloride, another chaotropic agent, also shows a similar effect. Our results show electrostatic interaction may play a role in neutral to basic transition in HSA. This study further supports the claim that at millimolar concentrations the chaotropes may act as kosmotropes for proteins.
authors.affiliation: Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, India.
authors.forename: Priyankar
authors.initials: P
authors.lastname: Sen
authors.forename: Mohd Moin
authors.initials: MM
authors.lastname: Khan
authors.forename: Asif
authors.initials: A
authors.lastname: Equbal
authors.forename: Ejaz
authors.initials: E
authors.lastname: Ahmad
authors.forename: Rizwan Hasan
authors.initials: RH
authors.lastname: Khan
mesh_terms: D003902:Detergents / Q000737:chemistry*; D019791:Guanidine / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D008958:Models, Molecular; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012709:Serum Albumin / Q000737:chemistry*; D012996:Solutions; D014508:Urea / Q000737:chemistry*
chemical_list: D003902:Detergents; D008823:Micelles; D012709:Serum Albumin; D012996:Solutions; D014508:Urea; D019791:Guanidine