M. Wada et al., Purification and characterization of monovalent cation-activated levodionereductase from Corynebacterium aquaticum M-13, APPL ENVIR, 65(10), 1999, pp. 4399-4403
(6R)-2,2,6-Trimethyl-1,4-cyclohexanedione (levodione) reductase was isolate
d from a cell extract of the soil isolate Corynebacterium aquaticum M-13, T
his enzyme catalyzed regio- and stereoselective reduction of levodione to (
4R,6R)-4-hydroxy-2,2,6-trimethylcyclohexanone (actinol). The relative molec
ular mass of the enzyme was estimated to be 142,000 Da by high-performance
gel permeation chromatography and 36,000 Da by sodium dodecyl sulfate-polya
crylamide gel electrophoresis. The enzyme required NAD(+) or NADH as a cofa
ctor, and it catalyzed reversible oxidoreduction between actinol and levodi
one, The enzyme was highly activated by monovalent cations, such as K+, Na, and NH4+. The NH2-terminal and partial amino acid sequences of the enzyme
showed that it belongs to the short-chain alcohol dehydrogenase/reductase
family. This is the first report of levodione reductase.