title: Heme oxygenase: evolution, structure, and mechanism.
abstract: Heme oxygenase has evolved to carry out the oxidative cleavage of heme, a reaction essential in physiological processes as diverse as iron reutilization and cellular signaling in mammals, synthesis of essential light-harvesting pigments in cyanobacteria and higher plants, and the acquisition of iron by bacterial pathogens. In all of these processes, heme oxygenase has evolved a similar structural and mechanistic scaffold to function within seemingly diverse physiological pathways. The heme oxygenase reaction is catalytically distinct from that of other hemoproteins such as the cytochromes P450, peroxidases, and catalases, but shares a hemoprotein scaffold that has evolved to generate a distinct activated oxygen species. In the following review we discuss the evolution of the structural and functional properties of heme oxygenase in light of the recent crystal structures of the mammalian and bacterial enzymes.
authors.affiliation: Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD 21201-1180, USA. awilks@rx.maryland.edu
authors.forename: Angela
authors.initials: A
authors.lastname: Wilks
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001664:Biliverdine / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D019143:Evolution, Molecular; D006418:Heme / Q000737:chemistry / Q000378:metabolism; D006419:Heme Oxygenase (Decyclizing) / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010100:Oxygen / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D016415:Sequence Alignment; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D007527:Isoenzymes; D006418:Heme; D006419:Heme Oxygenase (Decyclizing); D001664:Biliverdine; D010100:Oxygen