Camphor monooxygenase

Sligar, S. G., and Gunsalus, I. C., 1976, A thermodynamic model of regulation Modulation of redox equilibria in camphor monooxygenase, Proc. Natl. Acad. Sci. USA 73 1078nl082. 

Fig. 10.11. 3D view of a cytochrome P450cam (Camphor Monooxygenase) (EC 1.14.15.1) with bound camphor. This structure has been obtained from the Protein Data Bank and displayed with MolScript program. 

Camphor Monooxygenase Origin Pseudomonas putida Fluka... 

Of interest is the molecular mechanism by which the electron transfer takes place. For the bacterial camphor monooxygenase it was established by various independent methods that the putida redoxin forms a complex with the heme sulfur protein with a Km value of about 0.5-3 The carboxy terminal end of putida redoxin contains a tryptophan, which seems to participate in the binding, since its cleavage by carboxypeptidase A increases the Km for cytochrome P450 from 2-4 to 91 The formation of an enzyme-enzyme complex must also be postulated... 

Jones KH, RT Smith, PW Trudgill (1993) Diketocamphane enantiomer-specific Bayer-Villiger monooxygenases from camphor-grown Pseudomonas putida ATCC 17453. J Gen Microbiol 139 797-805. 

Ougham HJ, DG Taylor, PW Trudgill (1983) Camphor revisited involvement of a unique monooxygenase in metabolism of 2-oxo-A3-4,5,5-trimethylcyclopentenylacetic acid by Pseudomonas putida. J Bacteriol 15 140-152. 

Some types of bacteria (such as Pseudomonas, Aerobacter, and Klebsiella) utilize camphor, toluene, and other hydrocarbons as energy sources the induced enzymes are soluble forms of P-450, and in some instances the induction process appears to be controlled by plasmid genes.58 Simple eukaryotic cells, such as fungi,57 250 as well as simple and more highly evolved plants and animals,201 889 have detectable P-450-mediated monooxygenase activities that can be induced by chemicals under the proper conditions. 

Epoxidation of various olefins by cytochrome P-450 enzymes has been studied using rat liver microsomes [29,30] as well as using enzymes from microbial origin. For example, Ruettinger and Fulco [31] reported the epoxidation of fatty acids such as palmitoleic acid by a cytochrome P-450 from Bacillus megaterium. Their results indicate that both the epoxidation and the hydroxylation processes are catalyzed by the same NADPH-dependent monooxygenase. More recently, other researchers demonstrated that the cytochrome P-450cam from Pseudomonas putida, which is known to hydroxylate camphor at a non-activated carbon atom, is also responsible for stereoselective epoxidation of cis- -methylstyrene [32]. The (lS,2R)-epoxide enantiomer obtained showed an enantiomeric purity (ee) of 78%. This result fits the predictions based on a theoretical approach (Fig. 2). 

Although reductive pathways are discussed in Section 6.4.4, examples involving both oxidative and reductive pathways have been observed, for example, in Pseudomonas putida strain G-786 in which the synthesis of cytochrome P-450 monooxygenase was induced by growth with camphor. 

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