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2j18
From Proteopedia
CHLOROPEROXIDASE MIXTURE OF FERRIC AND FERROUS STATES (LOW DOSE DATA SET)
Overview
The X-ray crystallographic analysis of redox-active systems may be complicated by photoreduction. Although radiolytic reduction by the probing X-ray beam may be exploited to generate otherwise short-lived reaction intermediates of metalloproteins, it is generally an undesired feature. Here, the X-ray-induced reduction of the three heme proteins myoglobin, cytochrome P450cam and chloroperoxidase has been followed by on-line UV-Vis absorption spectroscopy. All three systems showed a very rapid reduction of the heme iron. In chloroperoxidase the change of the ionization state from ferric to ferrous heme is associated with a movement of the heme-coordinating water molecule. The influence of the energy of the incident X-ray photons and of the presence of scavengers on the apparent reduction rate of ferric myoglobin crystals was analyzed.
About this Structure
2J18 is a Single protein structure of sequence from Leptoxyphium fumago. Full crystallographic information is available from OCA.
Reference
Cryoradiolytic reduction of crystalline heme proteins: analysis by UV-Vis spectroscopy and X-ray crystallography., Beitlich T, Kuhnel K, Schulze-Briese C, Shoeman RL, Schlichting I, J Synchrotron Radiat. 2007 Jan;14(Pt 1):11-23. Epub 2006 Dec 15. PMID:17211068 Page seeded by OCA on Sun May 4 08:12:24 2008
