Enzyme conjugation to the polysaccharide chitosan: smart biocatalysts and biocatalytic hydrogels.
Laccase from Coriolopsis gallica was conjugated to the renewable biopolymer chitosan using carbodiimide chemistry. The laccase-chitosan conjugate was observed to offer three unique properties. First, the laccase-chitosan conjugate displayed pH-responsive behavior such that the conjugate was soluble and active under acidic conditions, but precipitated when the pH was raised toward neutrality. Second, the laccase-chitosan conjugate was more stable than free laccase at extreme pHs. At pH 1, the inactivation rate constant (k(in)) for the soluble laccase-chitosan conjugate was 20-fold less than that for free laccase. At pH 13, k(in) for the insoluble laccase-chitosan conjugate was nearly 3-fold less than that for free laccase. Finally, the laccase-chitosan conjugate could be cross-linked under mild conditions to create biocatalytic hydrogels. Potential benefits for enzyme-chitosan conjugates are discussed.
Vazquez-Duhalt
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Instituto de Biotecnologia UNAM, Apartado Postal 510-3, Cuernavaca, Morelos, 62250 Mexico.
Tinoco
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D'Antonio
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Topoleski
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LD
Payne
G F
GF
D001704:Biopolymers / Q000737:chemistry*; D002384:Catalysis; D002686:Chitin / Q000031:analogs & derivatives / Q000737:chemistry*; D048271:Chitosan; D003432:Cross-Linking Reagents / Q000737:chemistry; D004795:Enzyme Stability; D005976:Glutaral / Q000737:chemistry; D020100:Hydrogels / Q000138:chemical synthesis* / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D042845:Laccase; D015394:Molecular Structure; D010088:Oxidoreductases / Q000737:chemistry* / Q000378:metabolism
D001704:Biopolymers; D003432:Cross-Linking Reagents; D020100:Hydrogels; D002686:Chitin; D048271:Chitosan; D010088:Oxidoreductases; D042845:Laccase; D005976:Glutaral