title: Preferential interactions between protein and arginine: effects of arginine on tertiary conformational and colloidal stability of protein solution.
abstract: The purpose of this study was to better understand the preferential binding behavior of arginine to protein as well as the impact of arginine on the conformational and colloidal stability of protein solution. Physical stabilities of model proteins, bovine serum albumin (BSA) and ovalbumin (OVA), were investigated by fluorescence-based and dynamic light scattering techniques in the absence and presence of arginine. We investigated the interactions between arginine and tryptophan or tyrosine residues by conducting solubility and fluorescence studies of two amino acid derivatives, N-acetyl-l-tryptophanamide (NATA) and N-acetyl-l-tyrosinamide (NAYA), in arginine solutions. The result showed that arginine preferentially bond to the aromatic amino acids of proteins mainly through hydrogen bonds and Van der Waals' forces, while the binding constant K of arginine with BSA and OVA at 298K was 41.92 and 5.77L/mol, respectively. The fluorescence quenching, the decreased fluorescence lifetime and the red-shifted ANS peak position revealed that arginine perturbed the local environment of tryptophan and tyrosine residues. We also found the attenuated electrostatic repulsion among BSA and OVA molecules after adding arginine. These findings provided strong evidence that arginine possessed negative effects on tertiary conformational and colloidal stability of BSA and OVA during the preferential binding process.
authors.affiliation: Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan Province, PR China.
authors.forename: Lili
authors.initials: L
authors.lastname: Wen
authors.affiliation: Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan Province, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan Province, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Liao
authors.affiliation: Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan Province, PR China.
authors.forename: Xianxian
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan Province, PR China. Electronic address: yzn@scu.edu.cn.
authors.forename: Zongning
authors.initials: Z
authors.lastname: Yin
mesh_terms: D001120:Arginine / Q000737:chemistry*; D003102:Colloids; D010047:Ovalbumin / Q000737:chemistry*; D055550:Protein Stability; D017434:Protein Structure, Tertiary; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D014364:Tryptophan / Q000031:analogs & derivatives* / Q000737:chemistry; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D003102:Colloids; C019142:N-acetyltyrosylamide; C016952:N-acetyltryptophanamide; D012710:Serum Albumin, Bovine; D014443:Tyrosine; D014364:Tryptophan; D010047:Ovalbumin; D001120:Arginine
keywords: Arginine; Bovine serum albumin; Colloidal stability; Ovalbumin; Tertiary conformational stability