In chloroperoxidase

Ayala, M. Robledo, N. R. Lopez-Munguia, A., and Vazquez-Duhalt, R., Substrate specificity and ionization potential in chloroperoxidase-catalyzed oxidation of diesel fuel. Environmental Science Technology, 2000. 34(13) pp. 2804-2809. 

Chiappe C., Neri, L. and Pieraccini, D., Application of hydrophilic ionic liquids as co-solvents in chloroperoxidase catalyzed oxidations. Tetrahedron Lett., 2006, 47, 5089. 

Libby RD, Shedd AL, Phipps AK, Beachy TM, Gerstberger SM (1992) Defining the Involvement of HOC1 or Cl2 as Enzyme-Generated Intermediates in Chloroperoxidase-catalyzed Reactions. J Biol Chem 267 1769... 

Libby RD, Beachy TM, Phipps AK (1996) Quantitating Direct Chlorine Transfer from Enzyme to Substrate in Chloroperoxidase-Catalyzed Reactions. J Biol Chem 271 21820... 

Yi X, Mroczko M, Manoj KM, Wang X, Hager LP (1999) Replacement of the Proximal Heme Thiolate Ligand in Chloroperoxidase with a Histidine Residue. Proc Natl Acad Sci U S A 96 12412... 

Yi X, Conesa A, Punt PJ, Hager LP (2003) Examining the Role of Glutamic Acid 183 in Chloroperoxidase Catalysis. J Biol Chem 278 13855... 

Green MT, Dawson JH, Gray HB (2004) OxoironflV) in chloroperoxidase compound II is basic implications for P450 chemistry. Science 304 1653-1656... 

Four-valent iron centers are well known as catalytic intermediates in enzymatic heme catalysis. The catalytic cycles of, for example, catalase, peroxidase, and cytochrome P450, all have in common an intermediate that is comprised of a ferryl Fe(lV) and a further oxidation equivalent located either on the heme ring or on the protein moiety. This reaction intermediate is called compound 1 (cpd 1) and has a system spin of 5 = 1/2 (e.g., in chloroperoxidase) or 5 = 3/2 (e.g.. 

Fig. 1 Reactions involving molecular oxygen and its reduced congeners in heme proteins. Reactions where equilibria are manifest are indicated as such. In globins, peroxidases, cytochrome oxidases, and heme oxygenases, the axial ligand X is a protein-derived histidine in catalases, X is a tyrosine phenolate in chloroperoxidases and cytochromes P450, X is a cysteine thiolate...

Haloperoxidases have been shown to transform alkenes by a formal addition of hypohalous acid to produce halohydrins. The reaction mechanism of enzymatic halogenatitHi has been debated for some time and it is now accepted that it proceeds via a halonium intermediate [1770, 1771], similar to the chemical formation of halohydrins (Scheme 2.228). The former species is derived from hypohalous acid or molecular halogen, which is in turn produced by the enzyme via oxidation of halide [1772]. In support of this, a HOCl-adduct of Fe -protoporphyrin IX was identified as a direct enzyme-halogen intermediate involved in chloroperoxidase-catalyzed halogenaticHi [1773]. 

Farm YC, Gerber NC, Osmulski PA, Hager LP, Sligar SG, Hoffinan BM. 1994. ENDOR determination of heme ligation in chloroperoxidase and comparison with cytochrome P450cam. J Am Chem Soc 116(13) 5989-5990. 

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