Chloroperoxidase catalysis

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

Colonna S, Gaggero N, CasellaL, Carrea G, Pasta P (1993) Enantioselective Epoxidation of Styrene Derivatives by Chloroperoxidase Catalysis. Tetrahedron Asym 4 1325... 

Hager LP, Lakner FJ, Basavapathruni A (1998) Chiral Synthons via Chloroperoxidase Catalysis. J Mol Catal B Enzym 5 95... 

Geigert J, Dalietos DJ, Neidleman SL, Lee TD, Wadsworth J (1983) Peroxide oxidation of primary alcohols to aldehydes by chloroperoxidase catalysis. Biochem Biophys Res Com-mun 114 1104-1108... 

Chloroperoxidase catalysis by, 58, 302 in chlorination of pyrazoles, 57, 337 Chlorophyll, thioaldehyde synthetic intermediate to, 55, 3 Chlorosulfonyl isocyanate, reaction with 2-arylhydrazono-3-oxobutanoate, 59, 148 Chromatography, of [l,2,4]triazolo[l,5-a]-pyrimidines, 57, 106 Chrom-3-enes, see 2//-l-Benzopyrans Chromium tricarbonyl complexes of 3,5-diphenyl-l-(alkyl- or oxido-)-thiabenzenes, 59, 206, 227 indoles, lithiation of, 56, 181, 184 of pyridine, 58, 160 pyridines, lithiation of, 56, 230, 239 of 2f/-thiopyrans, 59, 227 Chromones, see l-Benzopyran-4-ones Cinnamonitrile, a-cyano-, condensations with thio-, seleno-amides, 59, 184, 186 Cinnoline, nitration, MO calculation, 59, 302... 

Rai GP, Sakai S, Florez AM, Mogollon L, Hager LP (2001) Directed Evolution of Chloroperoxidase for Improved Epoxidation and Chlorination Catalysis. Adv Synth Catal 343 638... 

Metalloenzymes contain a bound metal ion as part of their structure. This ion can either partidpate directly in the catalysis, or stabilize the active conformation of the enzyme. In Lewis acid catalysis (typically with zinc, vanadium, and magnesium), the M"+ ion is used instead of H+. Many oxidoreductases use metal centers such as V, Mo, Co, and Fe in much the same way as homogeneous catalysis uses ligand-metal complexes. Figure 5.7 shows a simplified mechanism for the halide oxidation readion catalyzed by vanadium chloroperoxidase. The vanadium atom ads as a Lewis add, activating the bound peroxide [30]. 

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.. 

Okazaki O, Guengerich FP. Evidence for specific base catalysis in M-dealkylation reactions catalyzed by cytochrome P450 and chloroperoxidase. Differences in rates of deprotonation of aminium radicals as an explanation for high kinetic hydrogen isotope effects observed with peroxidases. / Biol Chem 1993 268 1546-52. 

A wide range of metal ions is present in metalloenzymes as cofactors. Copper zinc snperoxide dismntase is a metalloenzyme that nses copper and zinc to help catalyze the conversion of snperoxide anion to molecnlar oxygen and hydrogen peroxide. Thermolysin is a protease that nses a tightly bonnd zinc ion to activate a water atom, which then attacks a peptide bond. Aconitase is one of the enzymes of the citric acid cycle it contains several iron atoms bonnd in the form of iron-sulfur clusters, which participate directly in the isomerization of citrate to isocitrate. Other metal ions fonnd as cofactors in metalloenzymes include molybdenum (in nitrate rednctase), seleninm (in glutathione peroxidase), nickel (in urease), and vanadinm (in fungal chloroperoxidase). see also Catalysis and Catalysts Coenzymes Denaturation Enzymes Krebs Cycle. 

PS-b-PIAT Polymersomes CalB lipase, GOx, HRP, chloroperoxidase Therapeutics, biosensing, diagnostics, catalysis, conducting materials [10,44-46]... 

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