cDNA isolation and functional characterization of UDP-glucose 4-epimerase from Davallia divaricate

Abstract

UDP-glucose 4-epimerase (UGE) is a universal enzyme responsible for interconversion of UDP-glucose and UDP-galactose. However, the gene encoding UGE from Davallia divaricate is elusive. In this study, two UGE genes, ddUGE1 and ddUGE2, were isolated and cloned from D. divaricate using a transcriptome-guided search strategy. Two unigenes sharing high sequence identity with UGE homologous genes were selected from transcriptome assembly. The enzymes, further functionally expressed in Escherichia coli, exhibit narrow substrate specificity. The biochemical characterization assays of DdUGE1 and DdUGE2 showed good thermal and pH stability, and metal ion independence, which provides a meaningful feature for biotechnological applications.

Keywords:

• Davallia divaricate
• UDP-galactose
• UDP-glucose 4-epimerase

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the CAMS Innovation Fund for Medical Sciences (CAMS-2016-I2M-3–012) and National Mega-project for Innovative Drugs (2018ZX09711001-006-001).