P450-containing Systems - Overview

Overview

P450 enzymes usually act as terminal oxidase in multicomponent electron-transfer chains, called P450-containing monooxygenase systems, although self-sufficient non-monooxygenase P450s are also described. All known P450-containing monooxygenase systems share common structural and functional domain architecture. Apart from P450 itself, these systems contain one or more fundamental redox domains: FAD-containing flavoprotein or domain, FMN domain, ferredoxin and cytochrome b₅. These ubiquitous redox domains, in various combinations, are widely distributed in biological systems. FMN domain, ferredoxin or cytochrome b₅ transfer electrons between the flavin reductase (protein or domain) and P450. While P450-containing systems are found throughout all kingdoms of life, some organisms lack one or more of these redox domains.