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2ig9
From Proteopedia
Structure of a full-length Homoprotocatechuate 2,3-Dioxygenase from B. fuscum in a new spacegroup.
Overview
We report the structures of three intermediates in the O2 activation and insertion reactions of an extradiol ring-cleaving dioxygenase. A crystal of Fe2+-containing homoprotocatechuate 2,3-dioxygenase was soaked in the slow substrate 4-nitrocatechol in a low O2 atmosphere. The x-ray crystal structure shows that three different intermediates reside in different subunits of a single homotetrameric enzyme molecule. One of these is the key substrate-alkylperoxo-Fe2+ intermediate, which has been predicted, but not structurally characterized, in an oxygenase. The intermediates define the major chemical steps of the dioxygenase mechanism and point to a general mechanistic strategy for the diverse 2-His-1-carboxylate enzyme family.
About this Structure
2IG9 is a Single protein structure of sequence from Brevibacterium fuscum. Full crystallographic information is available from OCA.
Reference
Crystal structures of Fe2+ dioxygenase superoxo, alkylperoxo, and bound product intermediates., Kovaleva EG, Lipscomb JD, Science. 2007 Apr 20;316(5823):453-7. PMID:17446402 Page seeded by OCA on Sun May 4 07:28:02 2008
