Monooxygenases cyclohexanone monooxygenase

The product (6 hexanohde) is a cyclic ester or lactone (Section 19 15) Like the Baeyer-Vilhger oxidation an oxygen atom is inserted between the carbonyl group and a carbon attached to it But peroxy acids are not involved m any way the oxidation of cyclohexanone is catalyzed by an enzyme called cyclohexanone monooxygenase with the aid of certain coenzymes... 

Organic chemists often use enantiomencally homogeneous starting materials for the synthe SIS of complex molecules (see Chiral Drugs p 296) A novel preparation of the S enantiomer of compound B has been descnbed using a bacterial cyclohexanone monooxygenase enzyme system... 

The November, 2001 issue of the Journal of Chemical Education (pp. 1533-1534) describes an introductory biochemistry laboratory experiment involving cyclohexanone monooxygenase oxidation of cyclic ketones. 

Enantioselective oxidation of cyclic dithioacetals to monosulfoxides catalyzed by bacterial cyclohexanone monooxygenases 96CC2303. 

Cyclohexanone and Cyclopentanone Monooxygenases as Baeyer-Villigerases and Sulfoxidation Catalysts... 

Most biochemical and biocatalytic studies have been performed with type I B VMOs. This is partly because of the fact that they represent relatively uncomplicated monooxygenase systems. These monooxygenases are typically soluble and composed of only one polypeptide chain. Expression systems have been developed for a number of type I BVMOs while no recombinant expression has been reported for a type II BVMO. Cyclohexanone monooxygenase (CHMO) from an Acinetobacter sp. NCIMB9871 was the only recombinant available BVMO... 

Figure 3 Illustration of overlapping substrate specificities of four BVMOs. Cyclohexanone monooxygenase (CHMO), cyclopentanone monooxygenase (CPMO), 4-hydroxyacetophenone monooxygenase (HAPMO) and phenylacetone monooxygenase (PAMO). For each enzyme, several typical substrates are...

Flavoprotein 1,2-monooxygenases are used for the insertion of an atom of oxygen into the ring that is the first step in the degradation of both cyclopentanone and cyclohexanone before hydrolysis of the resulting lactones and dehydrogenation (Figure 3.5). There are two types of cycloalkanone... 

Walsh and coworkers oxidized ethyl p-tolyl sulfide on an analytical scale to the S-sulfoxide of 64% enantiomeric purity using a bacterial flavoenzyme cyclohexanone monooxygenase derived from Adnetobacter . Using a flavin adenine dinucleotide containing monooxygenase purified from hog liver microsomes yielded the R-sulfoxide of 90% enantiomeric purity. HPLC on a column containing a 3,5-dinitrobenzoyl-D-phenylglycine chiral stationary phase was used to determine the optical purity of the sulfoxides. 

Stereoselective oxygen transfer to the sulphur atom of alkyl aryl sulphides catalyzed by 2-flavoenzyme monooxygenases afforded optically active sulphoxides in high optical yields . For instance, with ethyl p-tolyl sulphide as substrate cyclohexanone monooxygenase from Actinetobacter produces predominantly (— )-(S)-sulphoxide with 64% e.e. In contrast, FAD-containing dimethylaniline monooxygenase purified from hog liver microsomes affords (+ )-(i )-enantiomer of this sulphoxide with 90% optical purity . ... 

Recently, an oxidative biotransformation of secondary amines into nitrones applying cyclohexanone monooxygenase, an enzyme isolated from Acinetobacter... 

Light DR, Waxman DJ, Walsh C. 1982. Studies on the chirality of sulfoxidation catalyzed by bacterial flavoenzyme cyclohexanone monooxygenase and hog liver flavin adenine dinucleotide containing monooxygenase. Biochemistry 21 2490-2498. 

Stereoselective Synthesis of )0-Hydroxy Sulfoxides Catalyzed by Cyclohexanone Monooxygenase... 

Colonna, S., Gaggero, N., Pasta, P., Ottolina G., Enantioselective oxidation of sulfides to sulfoxides catalysed by bacterial cyclohexanone monooxygenases. Chem. Commun., 1996, 2303. 

Ottolina, G., Bianchi, S., Belloni, B., Carrea, G. and Danieli, B., First asymmetric oxidation of tertiary amines by cyclohexanone monooxygenase. Tetrahedron Lett., 1999, 40, 8483. 

Colonna, S., Pironti, V., Carrea, G., Pasta, P. and Zambianchi, F., Oxidation of secondary amines by molecular oxygen and cyclohexanone monooxygenase. Tetrahedron, 2004,60, 569. 

Trudgill, P.W., Cyclohexanone 1,2-monooxygenase from Acinetobacter NCIMB 9871. Methods EnzymoL, 1990,188, 70. 

Doig, S.D., O Sullivan, L.M., Patel, S., Ward, J.M. and Woodley, J.M., Large scale production of cyclohexanone monooxygenase from Escherichia coli TOPIO pQR239. Enzyme Microb. TechnoL, 2001, 28, 265. 

Secundo, F., Zambianchi, F., Crippa, G., Carrea, G. and Tedeschi, G., Comparative study of the properties of wild type and recombinant cyclohexanone monooxygenase, an enzyme of synthetic interest. J. Mol. Catal. B Enzym., 2005, 34, 1. 

Stewart, J.D., Cyclohexanone monooxygenase a useful reagent for as3mimetric Baeyer-Villiger reactions. Curr. Org. Chem., 1998, 2, 195-216. 

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