Recombinant E.coli (Escherichia coli) and application thereof

Abstract

The invention discloses recombinant E.coli (Escherichia coli) and application thereof. The recombinant E.coli is obtained by transferring an L-VC (Vitamin C) glycosylase gene sourced from bifidobacterium longum IEF101 as shown in SEQ ID NO.1 into Escherichia coli host cells. A single glycosylated product AA-2G (2-0-alpha-D-glucosyl-L-VC) is efficiently produced by adopting a biological method through one-step catalytic conversion; the recombinant E.coli IEF-blsp101 is capable of efficiently synthesizing sucrose phosphorylase in cells, glycosylation reaction of the L-VC can be efficiently catalyzed by taking the L-VC and saccharose as substrates, 90 to 100 g / L of the AA-2G can be obtained by catalyzing within 45 to 72 hours, and the average production intensity is greater than 1.3g.L<-1>.h<-1>.

Description

(1) Technical field

[0001] The invention relates to a recombinant escherichia coli containing L-ascorbic acid glycosylase gene and its application for producing 2-O-α-D-glucosyl-L-ascorbic acid (AA-2G). (2) Technical background

[0002] L-Ascorbic acid (VC) is a common water-soluble vitamin and an essential nutrient element for the human body. Its structure is as follows: figure 1 shown. Lack of VC can cause scurvy, heart disease, cancer and other diseases. Because the human body cannot synthesize VC, it must be obtained from food. In addition, it can also be used as flavoring agent, reducing agent, antioxidant, bleaching agent, etc., and is widely used in the fields of food, cosmetics and medicine. However, VC itself is unstable, and the enol hydroxyl groups on the 2- and 3-carbon atoms in the molecule are easily oxidized and dissociated, which makes VC lose its reducing activity, thus limiting its application.

[0003] L-ascorbic acid derivatives mainly include metal sa...

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