2sbl
From Proteopedia
THE THREE-DIMENSIONAL STRUCTURE OF AN ARACHIDONIC ACID 15-LIPOXYGENASE
Overview
In mammals, the hydroperoxidation of arachidonic acid by lipoxygenases leads to the formation of leukotrienes and lipoxins, compounds that mediate inflammatory responses. Lipoxygenases are dioxygenases that contain a nonheme iron and are present in many animal cells. Soybean lipoxygenase-1 is a single-chain, 839-residue protein closely related to mammalian lipoxygenases. The structure of soybean lipoxygenase-1 solved to 2.6 angstrom resolution shows that the enzyme has two domains: a 146-residue beta barrel and a 693-residue helical bundle. The iron atom is in the center of the larger domain and is coordinated by three histidines and the COO- of the carboxyl terminus. The coordination geometry is nonregular and appears to be a distorted octahedron in which two adjacent positions are not occupied by ligands. Two cavities, in the shapes of a bent cylinder and a frustum, connect the unoccupied positions to the surface of the enzyme. The iron, with two adjacent and unoccupied positions, is poised to interact with the 1,4-diene system of the substrate and with molecular oxygen during catalysis.
About this Structure
2SBL is a Single protein structure of sequence from Glycine max. Full crystallographic information is available from OCA.
Reference
The three-dimensional structure of an arachidonic acid 15-lipoxygenase., Boyington JC, Gaffney BJ, Amzel LM, Science. 1993 Jun 4;260(5113):1482-6. PMID:8502991 Page seeded by OCA on Sun May 4 17:17:28 2008
