Nobuya Itoh

Purification of bromoperoxidase from Corallinapilulifera

Abstract Bromoperoxidase was purified from the crude extract of Corallina pilulifera (Corallinaeae, Rhodophyta) and found to be homogeneous upon disc gel electrophoresis by precipitation of ammonium sulfate and sequential column chromatographies of DEAE-Sepharose CL-6B, Sepharose 6B and Cellulofine GC-700m. The purified enzyme did not exhibit optical absorption spectra of a hemoprotein. Therefore, bromoperoxidase of C. pilulifera was completely distinguishable from other haloperoxidases which have heme-irons at the catalytic sites.

Immobilized bromoperoxidase of Corallina pilulifera as a multifunctional halogenating biocatalyst

Abstract The partially purified bromoperoxidase of Corallina pilulifera (Corallinaceae, Rhodophyta) was immobilized on the following matrices: Cellulofine (covalent binding), DEAE-Cellulofine (ionic binding), or alkylsilane treated Controlled-Pore Glass (physical adsorption), and entrapped in the soft gels using photo-crosslinkable resin prepolymer (ENT-2000), polyurethane prepolymer (PU-6), or κ-carrageenan. These different forms of immobilized bromoperoxidase were tested for the bromination reactions of monochlorodimedone and uracil. The immobilization techniques using DEAE-Cellulofine and ENT-2000 were found to be suitable for the bromoperoxidase reaction. The immobilized enzyme on DEAE-Cellulofine showed the highest activity and a half-life of 45 days when it was used for the conversion of uracil to 5-bromouracil.