PMID: 9699635 , Related PDB ids: 1A76, 1A77

Authors:

Hwang KY, Baek K, Kim HY, Cho Y

Title:

The crystal structure of flap endonuclease-1 from Methanococcus jannaschii.

Journal:

Nat Struct Biol. 1998 Aug;5(8):707-13.

Abstract:

Flap endonuclease-1 (FEN-1), a structure specific nuclease, is an essential enzyme for eukaryotic DNA replication and repair. The crystal structure of FEN-1 from Methanococcus jannaschii, determined at 2.0 A resolution, reveals an active site with two metal ions residing on top of a deep cleft where several conserved acidic residues are clustered. Near the active site, a long flexible loop comprised of many basic and aromatic residues forms a hole large enough to accommodate the DNA substrate. Deletion mutations in this loop significantly decreased the nuclease activity and specificity of FEN-1, suggesting that the loop is critical for recognition and cleavage of the junction between single and double-stranded regions of flap DNA.