Chloroperoxidase: Use of a Hydrogen Peroxide-Stat for Controlling Reactions and Improving Enzyme Performance

Hydrogen Peroxide in Biocatalysis. A Dangerous Liaison

“…Hydrogen peroxide is a useful oxidant [1][2][3] in many different biocatalytic reactions [8,49,51,52,205]. However, it is also able to seriously damage the chemical structure of the proteins, inactivating enzymes.…”

“…In the chloroperoxidase catalyzed oxidation of indole in tert-butyl alcohol/water mixtures, chloroperoxidase was stabilized towards oxidative destruction as long as indole was present in the reaction mixture but inactivation occurred in the absence of a reductant [205]. In contrast, chloroperoxidase was inactivated in water by hydrogen peroxide even when indole was present in the reaction mixture and the oxidant concentration was as low as 30 μM.…”

Improvement of the total turnover number and space-time yield for chloroperoxidase catalyzed oxidation

“…Hydrogen peroxide sensors and dosing systems which recently have become commercially available are used for the disinfection and sterilization of equipment as well as for waste water treatment (Reinicke, 1996). In view of the deactivation of CPO by hydrogen peroxide mentioned above, we reasoned that such a hydrogen peroxide feed-on-demand system would further improve the catalyst performance (Deurzen et al, 1997). The merits of the various systems are discussed and the results are compared to other enzyme systems already established for the synthesis of amino acids and carbohydrates.…”

The rational design of semisynthetic peroxidases

“…After 15 min of stirring at 20°C the addition of thioanisole (0.90 M solution in dimethoxyethane/water mixture of 90:10 (v/v); 2.7 mol min −1 ) and hydrogen peroxide (0.30 M solution), using a hydrogen peroxide-stat (as described by Van Deurzen et al, 1997c), operated at 125 M H 2 O 2 were started. The formation of thioanisole sulfoxide was followed by HPLC.…”

“…1.11.1.10) from Caldariomyces fumago, have been shown to catalyze a wide variety of synthetically useful (enantioselective) oxygen transfer reactions with H 2 O 2 (Hager et al, 1998;Van Deurzen et al, 1997a), e.g., asymmetric epoxidation of olefins (Allain et al, 1993;Dexter et al, 1995;Lakner and Hager, 1996), benzylic, propargylic, and allylic hydroxylation (Hu and Hager, 1999;Miller et al, 1995;Zaks and Dodds, 1995), asymmetric sulfoxidation (Colonna et al, 1992(Colonna et al, , 1997Van Deurzen et al, 1997b;Kobayashi et al, 1987), and oxidation of indoles to the corresponding 2-oxindoles (Corbett and Chipko, 1979;Van Deurzen et al, 1996). However, a major shortcoming of all heme-dependent peroxidases, such as CPO, is their low operational stability (Van Deurzen et al, 1997c), resulting from facile oxidative degradation of the porphyrin ring. In contrast, vanadium haloperoxidases, such as vanadium chloroperoxidase from Curvularia inaequalis (Messerschmidt and Wever, 1996;Van Schijndel et al, 1993 are non-heme enzymes and, hence, are much more stable.…”