1qv0

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Revision as of 22:53, 20 November 2007

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spinqualitylabelsall models 1qv0, resolution 1.10Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Atomic resolution structure of obelin from Obelia longissima

Overview

The spatial structure of the Ca(2+)-regulated photoprotein obelin has been, solved to resolution of 1.1A. Two oxygen atoms are revealed substituted at, the C2-position of the coelenterazine in contrast to the obelin structure, at 1.73A resolution where one oxygen atom only was disclosed. The electron, density of the second oxygen atom was very weak but after exposing the, crystals to a trace of Ca(2+), the electron densities of both oxygen atoms, became equally intense. In addition, one Ca(2+) was found bound in the, loop of the first EF-hand motif. Four of the ligands were provided by, protein residues Asp30, Asn32, Asn34, and the main chain oxygen of Lys36., The other two were from water molecules. From a comparison of B-factors, for the residues constituting the active site, it is suggested that the, variable electron densities observed in various photoprotein structures, could be attributed to different mobilities of the peroxy oxygen atoms.

About this Structure

1QV0 is a Single protein structure of sequence from Obelia longissima with CO, K, CZH and GOL as ligands. Active as Renilla-luciferin 2-monooxygenase, with EC number 1.13.12.5 Full crystallographic information is available from OCA.

Reference

Atomic resolution structure of obelin: soaking with calcium enhances electron density of the second oxygen atom substituted at the C2-position of coelenterazine., Liu ZJ, Vysotski ES, Deng L, Lee J, Rose J, Wang BC, Biochem Biophys Res Commun. 2003 Nov 14;311(2):433-9. PMID:14592432

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