Bacterial-derived alpha-L-rhamnosidase gene, gene expression and application thereof

Abstract

The invention relates to a bacterial-derived alpha-L-rhamnosidase gene, gene expression and application thereof. A bacterial strain Enterococcus avium capable of hydrolyzing rhamnetin-3-O-rhamnoside in total flavonoids of Loranthus tanakae into rhamnetin is screened out, two alpha-L-rhamnosidase genes EaRha1 and EaRha2 in bacteria are cloned and subjected to prokaryotic expression, and the target alpha-L-rhamnosidase is obtained. The enzymatic properties of the recombinant proteins EaRha1 and EaRha2 are studied to determine the hydrolysis mechanism of the two proteins on the flavonoid compounds, and a theoretical basis and a guiding effect are provided for biotransformation of the flavonoid compounds. pNPR is adopted as a substrate, the optimum pH of the recombinant protein EaRha1 is 7, the optimum temperature is 50 DEG C, and neohesperidin and naringin containing alpha-1, 2 glucosidic bonds and rutin containing alpha-1, 6 glucosidic bonds can be catalytically hydrolyzed by the recombinant protein EaRha1. Rhamnetin-3-O-rhamnoside is adopted as the substrate, the optimal pH value of the EaRha2 is 7, the optimal temperature is 60 DEG C, and the EaRha2 can hydrolyze rhamnetin-3-O-rhamnoside and quercitrin.

Description

technical field [0001] The invention belongs to the technical field of bioengineering, specifically, a bacterial-derived α-L-rhamnosidase gene, gene expression and application thereof. Background technique [0002] α-L-rhamnosidase is a kind of glycoside hydrolase that widely exists in nature and specifically cleaves terminal α-L-rhamnose from natural glycosides such as flavonoids and terpene-based glycosides. It is found in tissue cells and microorganisms, and its microorganisms come from a wide range of sources, most of which come from fungi. In early studies, scholars at home and abroad have done more research on α-L-rhamnosidase in fungi, especially Aspergillus is more common. In recent years, more and more bacteria have found α-L-rhamnosidase The presence. α-L-rhamnosidase is a class of enzymes with great research value. It can not only act on the glycosidic bonds directly connected between aglycon and sugar groups, but also hydrolyze the glycosidic bonds connected be...

AI Technical Summary

Problems solved by technology

In recent years, there have been many studies on rhamnetin at home and abroad, but the high price of rhamnetin limits its research and application.

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