1aiv
From Proteopedia
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APO OVOTRANSFERRIN
Overview
The three-dimensional crystal structure of hen apo-ovotransferrin has been, solved by molecular replacement and refined by simulated annealing and, restrained least squares to a 3.0-A resolution. The final model, which, comprises 5312 protein atoms (residues 1 to 686) and 28 carbohydrate atoms, (from two monosaccharides attached to Asn(473)), gives an R-factor of, 0.231 for the 11,989 observed reflections between 20.0- and 3.0-A, resolution. In the structure, both empty iron binding clefts are in the, open conformation, lending weight to the theory that Fe(3+) binding or, release in transferrin proceeds via a mechanism that involves domain, opening and closure. Upon opening, the domains rotate essentially as rigid, bodies. The two domains of the N-lobe rotate away from one another by 53, degrees, whereas the C-lobe domains rotate away each another by 35, degrees. These rotations take place about an axis that passes through the, two beta-strands, linking the domains. The domains of each lobe make, different contacts with one another in the open and closed forms. These, contacts form two interdomain interfaces on either side of the rotation, axis, and domain opening or closing produces a see-saw motion between, these two alternative close-packed interfaces. The interdomain disulfide, bridge (Cys(478)-Cys(671)), found only in the C-lobe, may restrict domain, opening but does not completely prevent it.
About this Structure
1AIV is a Single protein structure of sequence from Gallus gallus. Full crystallographic information is available from OCA.
Reference
Crystal structure of hen apo-ovotransferrin. Both lobes adopt an open conformation upon loss of iron., Kurokawa H, Dewan JC, Mikami B, Sacchettini JC, Hirose M, J Biol Chem. 1999 Oct 1;274(40):28445-52. PMID:10497206
Page seeded by OCA on Tue Nov 20 10:53:27 2007
