Photoresponsive Peptide and Polypeptide Systems. 13. Photoinduced Cross-Linked Gel and Biodegradation Properties of Copoly(l-lysine) Containing ε-7-Coumaryloxyacetyl-l-lysine Residues

Abstract

Copoly[LysLys(Cou)] containing -7-coumaryloxyacetyl-L-lysine [Lys(Cou)] residues were synthesized by the N-carboxyanhydride method. When the aqueous solutions of copoly[LysLys(Cou)] containing 5-10 mol % of Lys(Cou) are irradiated by light, the photo-cross-linking reaction proceeds slowly between coumarin moieties in the side chains to give a cis head-to-head cyclocoumarin, and after 6-24 h the solutions become transparent hydrogels. The gels exhibit solvent-induced reversible expansion and contraction behavior in water and in ethanol. The biodegradation of the hydrogels by some proteolytic enzymes and soil filamentous fungi has been investigated using photo-cross-linked copoly[LysLys(Cou)] gels. The photo-cross-linked copoly[Lys 90-95 Lys(Cou) 10-5 ] gels are degradable by trypsin and protease type XXIII or two microorganisms, Aspergillus oryzae and Penicillium citrinum, suggesting potential for a controlled biodegradation by the different cross-linking densities in the gel matrixes upon the controlled irradiation.

Polyion complex fiber and capsule formed by self-assembly of chitosan and gellan at solution interfaces

“…The results themselves are scientifically interesting and might offer some clues towards the understanding of biological counterion interaction such as blood and extracellular material systems, as well as understanding its biomimesis, which undoubtedly includes a protein and/or polysaccharide interaction process, together with biodegradation by microorganisms and enzymes 15,[30][31][32] involved in keeping both land and sea ecology clean.…”

Coumarins in Polymers: From Light Harvesting to Photo-Cross-Linkable Tissue Scaffolds

“…Both studies found that the rate of biodegradation of both polymers by enzymes (trypsin or protease type XXIII) or by soil fungi was controlled by the ratio of coumarinated to native protein and by the cross-link density of the polypeptides. 176,182 Matsuda and co-workers synthesized 4-arm stars based on random copolymers of -caprolactone (CL) and trimethylene carbonate (TMC) and subsequently endcapped the arms at the hydroxyl terminus with coumarin groups (poly(CL/TMC)). [172][173][174][175]197 The chemical structure of the stars is shown in Figure 29.…”

Synthesis and Conformation of Star‐Shaped Poly(γ‐benzyl‐L‐glutamate)s on a Cyclotriphosphazene Core

“…[1][2][3][4][5][6][7][8][9] Functionalities on the basis of the helical structure of polyamino acid derivatives are of great interest from biotechnological points of view. However, peptide mimics are not always as good as the expectation for the synthetic polymers, probably due to the lack of organized ternary structure of the polymers employed as functional materials.…”