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1ev7
From Proteopedia
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CRYSTAL STRUCTURE OF DNA RESTRICTION ENDONUCLEASE NAEI
Overview
NAE:I is transformed from DNA endonuclease to DNA topoisomerase and, recombinase by a single amino acid substitution. The crystal structure of, NAE:I was solved at 2.3 A resolution and shows that NAE:I is a dimeric, molecule with two domains per monomer. Each domain contains one potential, DNA recognition motif corresponding to either endonuclease or, topoisomerase activity. The N-terminal domain core folds like the other, type II restriction endonucleases as well as lambda-exonuclease and the, DNA repair enzymes MutH and Vsr, implying a common evolutionary origin and, catalytic mechanism. The C-terminal domain contains a catabolite activator, protein (CAP) motif present in many DNA-binding proteins, including the, type IA and type II topoisomerases. Thus, the NAE:I structure implies that, DNA processing enzymes evolved from a few common ancestors. NAE:I may be, an evolutionary bridge between endonuclease and DNA processing enzymes.
About this Structure
1EV7 is a Single protein structure of sequence from Lechevalieria aerocolonigenes. Active as Type II site-specific deoxyribonuclease, with EC number 3.1.21.4 Full crystallographic information is available from OCA.
Reference
Crystal structure of NaeI-an evolutionary bridge between DNA endonuclease and topoisomerase., Huai Q, Colandene JD, Chen Y, Luo F, Zhao Y, Topal MD, Ke H, EMBO J. 2000 Jun 15;19(12):3110-8. PMID:10856254
Page seeded by OCA on Tue Nov 20 14:20:42 2007
