1iqr

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spinqualitylabelsall models 1iqr, resolution 2.1Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Crystal structure of DNA photolyase from Thermus thermophilus

Overview

DNA photolyase is a pyrimidine-dimer repair enzyme that uses visible, light. Photolyase generally contains two chromophore cofactors. One is a, catalytic cofactor directly contributing to the repair of a, pyrimidine-dimer. The other is a light-harvesting cofactor, which absorbs, visible light and transfers energy to the catalytic cofactor. Photolyases, are classified according to their second cofactor into either a folate- or, deazaflavin-type. The native structures of both types of photolyases have, already been determined, but the mechanism of substrate recognition, remains largely unclear because of the lack of structural information, regarding the photolyase-substrate complex. Photolyase from Thermus, thermophilus, the first thermostable class I photolyase found, is, favorable for function analysis, but even the type of the second cofactor, has not been identified. Here, we report the crystal structures of T., thermophilus photolyase in both forms of the native enzyme and the complex, along with a part of its substrate, thymine. A structural comparison with, other photolyases suggests that T. thermophilus photolyase has structural, features allowing for thermostability and that its light-harvesting, cofactor binding site bears a close resemblance to a deazaflavin-type, photolyase. One thymine base is found at the hole, a putative, substrate-binding site near the catalytic cofactor in the complex form., This structural data for the photolyase-thymine complex allow us to, propose a detailed model for the pyrimidine-dimer recognition mechanism.

About this Structure

1IQR is a Single protein structure of sequence from Thermus thermophilus with PO4 and FAD as ligands. Active as Deoxyribodipyrimidine photo-lyase, with EC number 4.1.99.3 Full crystallographic information is available from OCA.

Reference

Crystal structure of thermostable DNA photolyase: pyrimidine-dimer recognition mechanism., Komori H, Masui R, Kuramitsu S, Yokoyama S, Shibata T, Inoue Y, Miki K, Proc Natl Acad Sci U S A. 2001 Nov 20;98(24):13560-5. Epub 2001 Nov 13. PMID:11707580

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