title: The catalytic pathway of horseradish peroxidase at high resolution.
abstract: A molecular description of oxygen and peroxide activation in biological systems is difficult, because electrons liberated during X-ray data collection reduce the active centres of redox enzymes catalysing these reactions. Here we describe an effective strategy to obtain crystal structures for high-valency redox intermediates and present a three-dimensional movie of the X-ray-driven catalytic reduction of a bound dioxygen species in horseradish peroxidase (HRP). We also describe separate experiments in which high-resolution structures could be obtained for all five oxidation states of HRP, showing such structures with preserved redox states for the first time.
authors.affiliation: Department of Biochemistry, Uppsala University, Biomedical Center, Box 576, S-751 23 Uppsala, Sweden.
authors.forename: Gunnar I
authors.initials: GI
authors.lastname: Berglund
authors.forename: Gunilla H
authors.initials: GH
authors.lastname: Carlsson
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Smith
authors.forename: Hanna
authors.initials: H
authors.lastname: Szöke
authors.forename: Anette
authors.initials: A
authors.lastname: Henriksen
authors.forename: Janos
authors.initials: J
authors.lastname: Hajdu
mesh_terms: D002384:Catalysis / Q000528:radiation effects; D003460:Crystallization; D018360:Crystallography, X-Ray; D006735:Horseradish Peroxidase / Q000737:chemistry* / Q000378:metabolism*; D007501:Iron / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D010084:Oxidation-Reduction / Q000528:radiation effects; D010100:Oxygen / Q000378:metabolism*; D011487:Protein Conformation / Q000528:radiation effects; D014965:X-Rays
chemical_list: D007501:Iron; D006735:Horseradish Peroxidase; D010100:Oxygen