1FOK

STRUCTURE OF RESTRICTION ENDONUCLEASE FOKI BOUND TO DNA

Summary for 1FOK

• Entry DOI: 10.2210/pdb1fok/pdb
• Descriptor: DNA (5'-D(*TP*CP*GP*GP*AP*TP*GP*AP*TP*AP*AP*CP*GP*CP*TP*AP*G P*TP*CP*A)-3'), DNA (5'-D(*AP*TP*GP*AP*CP*TP*AP*GP*CP*GP*TP*TP*AP*TP*CP*AP*T P*CP*CP*G)-3'), PROTEIN (FOKI RESTRICTION ENDONUCLEASE), ... (4 entities in total)
• Functional Keywords: complex (endonuclease-dna), type iis, restriction endonuclease, deoxyribonuclease, dna hydrolysis, dna cleavage, hydrolase-dna complex, hydrolase/dna
• Biological source: Planomicrobium okeanokoites; More
• Total number of polymer chains: 3
• Total formula weight: 77786.20

Authors

Aggarwal, D.A.,Wah, J.A.,Hirsch, L.F.,Dorner, I.,Schildkraut, A.K. (deposition date: 1997-04-18, release date: 1997-12-03, Last modification date: 2024-02-07)

Primary citation

Wah, D.A.,Hirsch, J.A.,Dorner, L.F.,Schildkraut, I.,Aggarwal, A.K.
Structure of the multimodular endonuclease FokI bound to DNA.
Nature, 388:97-100, 1997

PubMed Abstract: FokI is a member of an unusual class of bipartite restriction enzymes that recognize a specific DNA sequence and cleave DNA nonspecifically a short distance away from that sequence. Because of its unusual bipartite nature, FokI has been used to create artificial enzymes with new specificities. We have determined the crystal structure at 2.8A resolution of the complete FokI enzyme bound to DNA. As anticipated, the enzyme contains amino- and carboxy-terminal domains corresponding to the DNA-recognition and cleavage functions, respectively. The recognition domain is made of three smaller subdomains (D1, D2 and D3) which are evolutionarily related to the helix-turn-helix-containing DNA-binding domain of the catabolite gene activator protein CAP. The CAP core has been extensively embellished in the first two subdomains, whereas in the third subdomain it has been co-opted for protein-protein interactions. Surprisingly, the cleavage domain contains only a single catalytic centre, raising the question of how monomeric FokI manages to cleave both DNA strands. Unexpectedly, the cleavage domain is sequestered in a 'piggyback' fashion by the recognition domain. The structure suggests a new mechanism for nuclease activation and provides a framework for the design of chimaeric enzymes with altered specificities.

PubMed: 9214510
DOI: 10.1038/40446

Experimental method

X-RAY DIFFRACTION (2.8 Å)