The catalytic pathway of horseradish peroxidase at high resolution.
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.
Berglund
Gunnar I
GI
Department of Biochemistry, Uppsala University, Biomedical Center, Box 576, S-751 23 Uppsala, Sweden.
Carlsson
Gunilla H
GH
Smith
Andrew T
AT
Szöke
Hanna
H
Henriksen
Anette
A
Hajdu
Janos
J
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
D007501:Iron; D006735:Horseradish Peroxidase; D010100:Oxygen