Immobilisation of P450 BM-3 and an NADP+ cofactor recycling system : towards a technical application of heme-containing monooxygenases in fine chemical synthesis

Abstract

Cytochrome P450 monooxygenases are potentially a very useful class of hydroxylation catalysts; they are able to introduce oxygen at activated and non-activated carbon-hydrogen bonds and thus lead to regio- and/or stereochemically pure compounds. However, this potential is lowered by their intrinsic low activity and inherent instability. P450-catalysed biotransformations require a constant supply of NAD(P)H, making the process an expensive one. To render these catalysts more suitable for industrial biocatalysis, the immobilisation of P450 BM-3 (CYP 102A1) from Bacillus megaterium in a sol-gel matrix was combined with a cofactor recycling system based on NADPƒy-dependent formate dehydrogenase (EC 1.2.1.2) from Pseudomonas sp. 101 and tested for practical applicability. This approach was used for the conversion of £]-ionone, octane and naphthalene to the respective hydroxy-compounds with DMSO as cosolvent using sol-gel immobilised P450 BM-3 mutants.