title: High conversion in asymmetric hydrolysis during permeation through enzyme-multilayered porous hollow-fiber membranes.
abstract: We describe a novel porous hollow-fiber support for immobilizing aminoacylase in multilayers. Epoxy-group-containing polymer chains were grafted onto a porous hollow-fiber membrane by radiation-induced graft polymerization of glycidyl methacrylate, and subsequently a diethylamino group as an anion-exchange group was introduced into the graft chain. Aminoacylase was adsorbed in multilayers by allowing the amioacylase buffer solution to permeate through the pores across the hollow fiber; the graft chains provided three-dimensional space for the enzymes because of their electrostatic repulsion. The adsorbed enzyme at a degree of multilayer binding of 15 was cross-linked with glutaraldehyde to prevent leakage. An acetyl-DL-methionine solution was allowed to permeate through the pores surrounded by the aminoacylase-immobilized graft chain. Production of L-methionine was observed at a 4.1 mol/h per L of the fiber for a space velocity of 200 h(-1), defined as the flow rate of the effluent penetrating the outside surface of the hollow fiber divided by the membrane volume including the lumen.
authors.affiliation: Department of Materials Technology, Faculty of Engineering, Chiba University, Inage, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kawai
authors.forename: M
authors.initials: M
authors.lastname: Nakamura
authors.forename: K
authors.initials: K
authors.lastname: Sugita
authors.forename: K
authors.initials: K
authors.lastname: Saito
authors.forename: T
authors.initials: T
authors.lastname: Sugo
mesh_terms: D000581:Amidohydrolases / Q000378:metabolism*; D000596:Amino Acids / Q000302:isolation & purification; D003432:Cross-Linking Reagents / Q000737:chemistry; D004800:Enzymes, Immobilized / Q000378:metabolism*; D004867:Equipment Design; D005976:Glutaral / Q000737:chemistry; D006868:Hydrolysis; D008567:Membranes, Artificial; D008715:Methionine / Q000302:isolation & purification; D010539:Permeability; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D003432:Cross-Linking Reagents; D004800:Enzymes, Immobilized; D008567:Membranes, Artificial; D008715:Methionine; D000581:Amidohydrolases; C019672:aminoacylase I; D005976:Glutaral