Microbial P450 enzymes in biotechnology

Abstract

Oxidations are key reactions in chemical syntheses. Biooxidations using fermentation processes have already conquered some niches in industrial oxidation processes, since they allow the introduction of oxygen even into non-activated carbon atoms in a sterically and optically selective manner which is difficult or impossible to achieve by synthetic organic chemistry. Biooxidation using isolated enzymes is limited to oxidases and dehydrogenases. In addition, P450-catalyzed reactions require a constant supply of NAD(P)H which makes continuous cell-free processes very expensive. Quite recently, several groups have started to investigate cost-efficient ways which could allow the continuous supply of electrons to the heme iron. These include, for example, the use of electron mediators, direct electron supply from electrodes and enzymatic approaches. In addition, methods of protein design and directed evolution have been applied in an attempt to enhance the activity of the enzymes and improve their selectivity. The promising application of bacterial P450s as catalyzing agents in biocatalytic reactions and recent progress made in this field are covered in this review.3

Preparation of human drug metabolites using fungal peroxygenases

“…The obvious route is to use isolated human P450s, but these complex multiprotein systems are membrane-bound, poorly stable, cofactor-dependent, and generally exhibit low reaction rates [7,8]. More promising results have been reported for laboratory-evolved bacterial P450s, which are capable of catalyzing the H 2 O 2 -dependent hydroxylation of pharmaceuticals via the "peroxide shunt" pathway [9].…”

Catalytic Hydroxylation in Biphasic Systems using CYP102A1 Mutants

“…Considering these problems, the use of isolated oxygenases in enzyme reactors could be advantageous. [6][7][8][9] Regarding the application of isolated P450 monooxygenases in fine chemical synthesis, enzymes from bacterial sources turned out as more suitable than those originating from plants, fungi or vertebrates: besides a much higher activity compared to eucaryotic enzymes, bacterial P450s exhibit in many cases higher stability. [10] P450 enzymes consisting of a heme domain fused to an FAD-and FMN-containing P450 reductase domain are -in contrast to the majority of P450s -"self-sufficient", i.e., they do not have to be supplied with additional redox partners (reductases) apart from NADPH.…”

Increased TCA cycle activity and reduced oxygen consumption during cytochrome P450‐dependent biotransformation in fission yeast

“…P450s utilize two electrons from NAD(P)H to activate dioxygen and are impressive for their ability to catalyse the insertion of oxygen into allylic positions, double bonds, or even into non-activated C-H bonds. This ability to catalyse reactions that are difficult to achieve chemically with high selectivity, especially in water, at room temperature and under atmospheric pressure, makes P450 enzymes attractive for biotechnological applications (Urlacher et al, 2004). However, some major disadvantages still exist, explaining why few industrially relevant processes exist.…”

“…Drǎgan, L. M. Blank and M. Bureik (Urlacher et al, 2004). However, a large number of reactions were developed at the laboratory scale, using a variety of host organisms (e.g.…”