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Updated: Jul 3, 2026

Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine
Published on: February 16, 2018
7alpha- and 12alpha-Hydroxysteroid dehydrogenases from Acinetobacter calcoaceticus lwoffii: a new integrated
Pier Paolo Giovannini1, Alessandro Grandini, Daniela Perrone
1Dipartimento di Biologia ed Evoluzione, Università di Ferrara, C.so Ercole I d'Este 32, I-44100 Ferrara, Italy.
Abstract:
We report the very efficient biotransformation of cholic acid to 7-keto- and 7,12-diketocholic acids with Acinetobacter calcoaceticus lwoffii. The enzymes responsible of the biotransformation (i.e. 7alpha- and 12alpha-hydroxysteroid dehydrogenases) are partially purified and employed in a new chemo-enzymatic synthesis of ursodeoxycholic acid starting from cholic acid. The first step is the 12alpha-HSDH-mediated total oxidation of sodium cholate followed by the Wolf-Kishner reduction of the carbonyl group to chenodeoxycholic acid. This acid is then quantitatively oxidized with 7alpha-HSDH to 7-ketochenodeoxycholic acid, that was chemically reduced to ursodeoxycholic acid (70% overall yield).
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