title: Tyrosinase-catalyzed synthesis of a universal coil-chitosan bioconjugate for protein immobilization.
abstract: Chitosan has been reported as a promising material for gene and drug delivery as well as for tissue engineering and regenerative medicine. We report here the conjugation of a de novo designed coil peptide (Kcoil) to chitosan ( M(n) = 200 kDa) to achieve a universal Kcoil-chitosan scaffold for subsequent immobilization of proteins tagged with the Kcoil partner, i.e., the Ecoil peptide. Kcoil-chitosan conjugate was synthesized using a tyrosinase-catalyzed protocol. Extensive UV/vis and IR characterization demonstrated that Kcoil peptide was covalently grafted to amines of chitosan. The ability of Kcoil-chitosan conjugate to recruit Ecoil tagged epidermal growth factor (EGF) was assessed by surface plasmon resonance measurements (SPR). Despite nonspecific interactions between chitosan and EGF, the specific formation of an E/K coiled coil complex was observed at slightly acidic pH and high salt concentration conditions, demonstrating that grafting to chitosan did not negatively impact binding characteristics of Kcoil peptide. Finally, the benefits of such bioconjugates for biomedical applications are discussed.
authors.affiliation: Department of Chemical Engineering, Institute of Biomedical Engineering, Ecole Polytechnique de Montréal, P.O. Box 6079, Station Centre-ville, Montréal, Québec H3C3A7, Canada.
authors.forename: Antoine
authors.initials: A
authors.lastname: Demolliens
authors.forename: Cyril
authors.initials: C
authors.lastname: Boucher
authors.forename: Yves
authors.initials: Y
authors.lastname: Durocher
authors.forename: Mario
authors.initials: M
authors.lastname: Jolicoeur
authors.forename: Michael D
authors.initials: MD
authors.lastname: Buschmann
authors.forename: Gregory
authors.initials: G
authors.lastname: De Crescenzo
mesh_terms: D000588:Amines / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D001672:Biocompatible Materials / Q000138:chemical synthesis*; D002384:Catalysis; D048271:Chitosan / Q000031:analogs & derivatives / Q000138:chemical synthesis*; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D014442:Monophenol Monooxygenase / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism; D012492:Salts / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000588:Amines; D001672:Biocompatible Materials; D010455:Peptides; D011506:Proteins; D012492:Salts; D048271:Chitosan; D014442:Monophenol Monooxygenase