To develop a bioreactor system using catalytic antibodies, the reaction properties of immobilized catalytic antibodies in aqueous dimethyl sulfoxide (DMSO) were studied. As a model system, the catalytic antibody 17E11, which selectively hydrolyzes the ester group at C-4 of the carbohydrates with two 4-(N-acetyl-amino)phenylacetyl groups at C-3 and C-4 to produce a monoester 4-oh exclusively, was used. 17E11 was immobilized onto CNBr-activated Sepharose 4B (17E11-sepharose 4B) and Formyl-cellulofine (17E11-cellulofine). 17E11-sepharose 4B and 17E11-cellulofine retained a high catalytic activity in 10% DMSO/50 mm Tris-HCl buffer, pH 8.2, and showed the activity up to 40% DMSO. Moreover, both the immobilized catalytic antibodies were stable and repeatedly used for the hydrolysis of the substrate in 10% DMSO/50 mM Tris- HCl, pH 8.2, without detectable activity reduction, indicating a high durability. The immobilized catalytic antibodies are advantageous for quick production and separation of products which are unstable under the reaction conditions. Model calculations based on the kinetic parameters obtained experimentally showed that unstable 4-OH can be produced with a high yield using an appropriate amount of immobilized 17E11. These results clearly show the effectiveness of immobilized catalytic antibodies and their applicability to bioreactor systems.
- acylated carbohydrates
- catalytic antibody
- regio- and stereoselective deprotection
ASJC Scopus subject areas
- Applied Microbiology and Biotechnology