Glyco-modification of protein with O-cyanate chain-end functionalized glycopolymer via isourea bond formation

Glycoengineering aimed at the addition of carbohydrates to proteins is an attractive approach to alter the pharmacokinetic properties of proteins, such as enhancing stability and prolonging the duration of action. We report a novel protein glyco-modification of BSA and recombinant thrombomodulin with O-cyanate chain-end functionalized glycopolymer via isourea bond formation. The protein glycoconjugates were confirmed by SDS-PAGE, western blot, and MALDI-TOF mass spectrometry. Protein C activation activity of the glyco-modified recombinant thrombomodulin was confirmed, proving no interference with activity from the glycopolymer modification. The isourea bond formation under mild conditions was demonstrated as an alternative method for protein modification with polymers.