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Preparation and In Vivo Use of an Activity-based Probe for N-acylethanolamine Acid Amidase
Published on: November 23, 2016
Biotransformation of amides to acids using a co-cross-linked enzyme aggregate of Rhodococcus erythropolis amidase
Hyun Joo Park1, Ki-Nam Uhm, Hyung Kwoun Kim
1Division of Biotechnology, The Catholic University of Korea, Bucheon 420-743, Korea.
Abstract:
Rhodococcus erythropolis amidase was expressed in Escherichia coli cells. The crude amidase in the cell-free extract was immobilized using the cross-linked enzyme aggregate (CLEA) method. The crude amidase was mixed with bovine serum albumin and then precipitated with ammonium sulfate. The resultant precipitant was subsequently cross-linked with glutaraldehyde. Scanning electron microscopy revealed that this co-CLEA had a ball-like shape of a diameter of approximately 1 micronm. This co-CLEA evidenced hydrolytic activity toward a variety of amide substrates. The amidase co-CLEA evidenced an optimum temperature of 60 degrees and an optimum pH of 8.0, results that were similar to those of the soluble amidase. The reaction stability of the co-CLEA was increased. That is, it was stable up to 50 degrees and in a pH range of 5.0-12.0. Additionally, the co-CLEA could be recovered by centrifugation, and retained 96% activity after 3 repeated cycles. This amidase co-CLEA may prove useful as a substitute for soluble amidase as a biocatalyst in the pharmaceutical and chemical industries.
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