Natural zinc ribbon HNH endonucleases and engineered zinc finger nicking endonuclease.

ABSTRACT: Many bacteriophage and prophage genomes encode an HNH endonuclease (HNHE) next to their cohesive end site and terminase genes. The HNH catalytic domain contains the conserved catalytic residues His-Asn-His and a zinc-binding site [CxxC](2). An additional zinc ribbon (ZR) domain with one to two zinc-binding sites ([CxxxxC], [CxxxxH], [CxxxC], [HxxxH], [CxxC] or [CxxH]) is frequently found at the N-terminus or C-terminus of the HNHE or a ZR domain protein (ZRP) located adjacent to the HNHE. We expressed and purified 10 such HNHEs and characterized their cleavage sites. These HNHEs are site-specific and strand-specific nicking endonucleases (NEase or nickase) with 3- to 7-bp specificities. A minimal HNH nicking domain of 76 amino acid residues was identified from Bacillus phage γ HNHE and sub

SUBMITTER: Xu SY 

PROVIDER: S-EPMC3592412 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature