NAD⁺ -Dependent Enzymatic Route for the Epimerization of Hydroxysteroids.

ABSTRACT: Epimerization of cholic and chenodeoxycholic acid (CA and CDCA, respectively) is a notable conversion for the production of ursodeoxycholic acid (UDCA). Two enantiocomplementary hydroxysteroid dehydrogenases (7α- and 7β-HSDHs) can carry out this transformation fully selectively by specific oxidation of the 7α-OH group of the substrate and subsequent reduction of the keto intermediate to the final product (7β-OH). With a view to developing robust and active biocatalysts, novel NADH-active 7β-HSDH species are necessary to enable a solely NAD⁺ -dependent redox-neutral cascade for UDCA production. A wild-type NADH-dependent 7β-HSDH from Lactobacillus spicheri (Ls7β-HSDH) was identified, recombinantly expressed, purified, and biochemically characterized. Using this novel NAD⁺

SUBMITTER: Tonin F 

PROVIDER: S-EPMC6681466 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature