1ev7
From Proteopedia
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. 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 Fri May 2 15:33:23 2008
