title: A comprehensive structure-function analysis shed a new light on molecular mechanism by which a novel smart copolymer, NY-3-1, assists protein refolding.
abstract: An in-depth understanding of molecular basis by which smart polymers assist protein refolding can lead us to develop a more effective polymer for protein refolding. In this report, to investigate structure-function relationship of pH-sensitive smart polymers, a series of poly(methylacrylic acid (MAc)-acrylic acid (AA))s with different MAc/AA ratios and molecular weights were synthesized and then their abilities in refolding of denatured lysozyme were compared by measuring the lytic activity of the refolded lysozyme. Based on our analysis, there were optimal MAc/AA ratio (44% MAc), M(w) (1700 Da), and copolymer concentration (0.1%, w/v) at which the highest yield of protein refolding was achieved. Fluorescence, circular dichroism, and RP-HPLC analysis reported in this study demonstrated that the presence of P(MAc-AA)s in the refolding buffer significantly improved the refolding yield of denatured lysozyme without affecting the overall structure of the enzyme. Importantly, our bioseparation analysis, together with the analysis of zeta potential and particle size of the copolymer in refolding buffers with different copolymer concentrations, suggested that the polymer provided a negatively charged surface for an electrostatic interaction with the denatured lysozyme molecules and thereby minimized the hydrophobic-prone aggregation of unfolded proteins during the process of refolding.
authors.affiliation: Key Laboratory of Biotechnology and Pharmaceutical Engineering of Zhejiang Province, Wenzhou Medical College, Wenzhou 325035, China.
authors.forename: Chaohui
authors.initials: C
authors.lastname: Ye
authors.forename: Dariush
authors.initials: D
authors.lastname: Ilghari
authors.forename: Jianlou
authors.initials: J
authors.lastname: Niu
authors.forename: Yaoyao
authors.initials: Y
authors.lastname: Xie
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.forename: Xiaokun
authors.initials: X
authors.lastname: Li
authors.forename: Bailin
authors.initials: B
authors.lastname: Liu
authors.forename: Zhifeng
authors.initials: Z
authors.lastname: Huang
mesh_terms: D004789:Enzyme Activation; D004795:Enzyme Stability; D009113:Muramidase / Q000737:chemistry*; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011489:Protein Denaturation; D017510:Protein Folding; D013329:Structure-Activity Relationship
chemical_list: D019904:Polymethyl Methacrylate; D009113:Muramidase