Stereoselective Carveol Dehydrogenase from Rhodococcus erythropolis DCL14

Abstract

A novel nicotinoprotein, catalyzing the dichlorophenolindophenol-dependent oxidation of carveol to carvone, was purified to homogeneity from Rhodococcus erythropolis DCL14. The enzyme is specifically induced after growth on limonene and carveol. Dichlorophenolindophenol-dependent carveol dehydrogenase (CDH) is a homotetramer of 120 kDa with each subunit containing a tightly bound NAD(H) molecule. The enzyme is optimally active at pH 5.5 and 50°C and displays a broad substrate specificity with a preference for substituted cyclohexanols. When incubated with a diastereomeric mixture of (4R)

Williopsis californica, Williopsis saturnus, and Pachysolen tannophilus: Novel microorganisms for stereoselective oxidation of secondary alcohols

“…Two strains from the Williopsis genus are the most active strains. There are only two active bacteria, Rhodococcus rhodochrous DSMZ 11097 and the well-reported Rhodococcus erythropolis ( Van der Werf et al, 1989;Van der Werf and Boot, 2000).…”

Biotechnological Flavour Generation

“…An unusual (4R,8R)-limonene-8,9-epoxide was the only transformation product when a Xanthobacter isolate selected on cyclohexane as the sole carbon source was exposed to (4R)-limonene (Van der Werf et al, 2000). Many other transformation pathways of limonene were compiled by the same authors ( Van der Werf et al, 1999). The conversion of ␤-myrcene by the edible fungus Pleurotus ostreatus was investigated using trideutero-labelled ␤-myrcene or presumed intermediates as the substrates.…”

“…Many possible sources of enzymes, for example marine organisms (Chandrasekaran, 1997), have remained almost unexplored so far. With the rapid progress in basic enzymological and genetic knowledge even NAD + -dependent redox enzymes gain interest, particularly if a synthetic electron sink, such as dichlorophenol indophenol, is accepted and high stereoselectivity is observed ( Van der Werf et al, 1999).…”

The Metabolic Formation and Utilization of 5‐Oxo‐ L ‐proline ( L ‐Pyroglutamate, L ‐Pyrrolidone Carboxylate)

“…In the presence of 150 mlkl potassium ions and 2 m M ATP, either magnesium ions or manganese ions were required at optimal concentrations of 1-2 mM. The apparent K,,, values of 5-oxo-~-prolinase for A T P and 5-oxo-~-proline were 0.17 m M and 0.05 mM, respectively (89,90). The enzyme exhibits activity over a broad range of p H (90).…”

“…The enzyme exhibits activity over a broad range of p H (90). 5-Oxoprolinase activity is inhibited by a number of sulfhydryl reagents including p-hydroxymercuribenzoate, N-ethylmaleamide, and iodoacetamide (30,90); thus, the enzyme is evidently a "sulfhydryl enzyme".…”