Method for preparing immobilized adenosylmethionine synthetase and adenosylmethionine

Abstract

The invention relates to a method for preparing immobilized adenosylmethionine synthetase and adenosylmethionine. The method has the following technical characteristics of: crosslinking amino resin carrier Seplite LX-1000HA and glutaraldehyde solution; and reacting the amino resin carrier crosslinked with glutaraldehyde with solution of recombinant adenosylmethionine synthetase to obtain the immobilized adenosylmethionine synthetase. The amino resin carrier has high protein fixation rate, the recovery rate of the enzyme activity of the immobilized adenosylmethionine synthetase is high, and the stability and continuous operation performance are good. When the immobilized adenosylmethionine synthetase is used for producing the adenosylmethionine, the reaction operation is simple, the production cycle is short, and products are easy to purify; the immobilized enzyme can be recycled, the production cost is greatly reduced, the production efficiency is improved, and a new way is provided for industrialized production of the adenosylmethionine.

Description

technical field [0001] The invention relates to a method for preparing immobilized adenosylmethionine synthetase, and a method for preparing adenosylmethionine by using the prepared immobilized adenosylmethionine synthetase, involving enzyme immobilization and the use of immobilized The technical field of enzyme-catalyzed synthesis of high-value compounds. Background technique [0002] S-adenosylmethionine (S-adenosylmethionine, SAM) is an important metabolic intermediate widely present in organisms, first discovered by Cantoni in 1952, with a relative molecular mass of 399. SAM is a pair of chiral substances, with two isomers: (R, S)-SAM and (S, S)-SAM, only (S, S)-SAM has biological activity. In organisms, SAM is synthesized by L-methionine (L-Met) and adenosine triphosphate (ATP) catalyzed by adenosylmethionine synthetase. Because SAM contains a high-energy sulfonium atom that can activate the nucleophilic attack reaction of adjacent carbon atoms, it has the effects of ...

AI Technical Summary

Problems solved by technology

Appling et al constructed a chimeric gene consisting of methylenetetrahydrofolate reductase and adenosylmethionine synthetase, transformed Saccharomyces cerevisiae to express SAM, and increased the conversion rate of L-methionine to 40% (Appling ; Dean R.United States Patent: 7,033,815); Although the technology of fermentative production of SAM is constantly improving, there are several inherent and difficult problems in the fermentative process: (1). The conversion rate of substrate L-methionine Low; (2). The fermentation product is a mixture of (-) SAM and (+) SAM, while (-) SAM with biological activity only accounts for about 70%, and (-) SAM and (+) SAM are difficult to separate; ( 3). The fermentation cycle of yeast is long (3-5 days), which requires a lot of energy consumption; (4). The composition of SAM solution after the yeast is broken is complex, and the extraction and purification process of SAM is various, so the recovery rate of SAM is low

However, in our research, we found that the adenosylmethionine synthetase immobilized with epoxy resin has no catalytic activity, which may be due to the cross-linking reaction between the epoxy group of the resin and the amino acid in the catalytic center of the enzyme, which leads to the inactivation of the enzyme.