Protein Folding Assisted by Covalent Hydrogel Based on Amphiphilic Supramolecular

A novel monomeric species, 2-{6-[3-(6-methyl-4-oxo-1,4-dihydropyrimidin-2-yl)ureido]hexylcarbamo-yloxy} butyl acrylate(UPy-C-6-HBA), was synthesized while 4-hydroxybutyl acrylate(HBA) was introduced to the intermediate compound 2-(6-isocyanatohexyl ureido)-6-methyl-4[1H] pyrimidinone(UPy-C-6-NCO) which was obtained through the reaction of 2-aminomethyl-4-hydroxy-6-methylpyrimidine(MIS) with 1,6-hexane diisocyanate (HDI). UPy-C-6-HBA together with acrylamide(AM) and N,N'-methylenediacrylamide(Bis) was polymerized by UV -induced free radical polymerization method, yielding physically crosslinked hydrogels that possessed a homogenous porous architecture and pronounced swelling capacity. Lysozyme was incorporated within the hydrogel matrix containing UPy-C-6-HBA monomer which in vitro refolding was facilitated via hydrophobic interactions. The effects of UPy-C-6-HBA concentration, hydrogel dosage, lysozyme concentration and refolding temperature on the refolding rate of lysozyme were meticulously investigated. Remarkably, the supramolecular hydrogel comprising UPy-C-6-HBA at a mass fraction of 15% exhibited a remarkable 41% enhancement in the refolding rate of lysozyme at 25 C-degrees compared with the control. These findings unequivocally demonstrate the addition of UPy-C-6-HBA monomer to the hydrogel matrix significantly improved the refolding rate of lysozyme, which is of great significance for the refolding of high concentration denatured lysozyme.