Highly efficient production of chiral amines in batch and continuous flow by immobilized ?-transaminases on controlled porosity glass metal-ion affinity carrier.

ABSTRACT: In this study, two stereocomplementary ?-transaminases from Arthrobacter sp. (AsR-?TA) and Chromobacterium violaceum (Cv-?TA) were immobilized via iron cation affinity binding onto polymer-coated controlled porosity glass beads (EziG^™). The immobilization procedure was studied with different types of carrier materials and immobilization buffers of varying compositions, concentrations, pHs and cofactor (PLP) concentrations. Notably, concentrations of PLP above 0.1?mM were correlated with a dramatic decrease of the immobilization yield. The highest catalytic activity, along with quantitative immobilization, was obtained in MOPS buffer (100?mM, pH 8.0, PLP 0.1?mM, incubation time 2?h). Leaching of the immobilized enzyme was not observed within 3 days of incubation. EziG-immobilized AsR-?TA and Cv-?TA retained elevated activity when tested for the kinetic resolution of rac-?-methylbenzylamine (rac-?-MBA) in single batch experiments. Recycling studies demonstrated that immobilized EziG³-AsR-?TA could be recycled for at least 16 consecutive cycles (15?min per cycle) and always affording quantitative conversion (TON ca. 14,400). Finally, the kinetic resolution of rac-?-MBA with EziG³-AsR-?TA was tested in a continuous flow packed-bed reactor (157??L reactor volume), which produced more than 5?g of (S)-?-MBA (>49% conversion, >99% ee) in 96?h with no detectable loss of catalytic activity. The calculated TON was more than 110,000 along with a space-time yield of 335?g L^-1?h^-1.

SUBMITTER: Bohmer W 

PROVIDER: S-EPMC7116800 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature