Ceska T A, Sayers J R
Celltech Therapeutics, Slough, Berkshire, UK.
Trends Biochem Sci. 1998 Sep;23(9):331-6. doi: 10.1016/s0968-0004(98)01259-6.
Many processes, such as DNA replication, recombination and repair, produce branched DNA structures. These bifurcated molecules are trimmed by a group of homologous 5'-3' exonucleases (also known as 5' nucleases) in structure-specific cleavage reactions. X-ray crystallographical and biochemical studies suggest that ssDNA substrates become threaded through the 5'-3' exonucleases, where hydrolysis is effected with the aid of divalent metal cations.
许多过程，如DNA复制、重组和修复，都会产生分支DNA结构。这些分叉分子在结构特异性切割反应中被一组同源的5'-3'核酸外切酶（也称为5'核酸酶）修剪。X射线晶体学和生化研究表明，单链DNA底物穿过5'-3'核酸外切酶，在二价金属阳离子的帮助下进行水解。
