可变鱼腥藻中两种序列特异性核酸内切酶的分离与鉴定

Murray K, Hughes S G, Brown J S, Bruce S A

Biochem J. 1976 Nov;159(2):317-22. doi: 10.1042/bj1590317.

Two endonucleases, AvaI and AvaII, were isolated from Anabaena variabilis on the basis of their ability to make a limited number of breaks at specific points in bacteriophage lambda DNA. Neither enzyme has cofactor requirements beyond Mg2+. Endonuclease AvaI makes eight breaks in the phage lambda chromosome at which the 5'-terminal sequence is pPy-C-G-N. AvaII endonuclease cuts phage lambda DNA more extensively, yielding fragments with the 5'-terminal sequence G-T-C-N or G-A-C-N. Neither enzyme generates cohesive ends.

根据它们在噬菌体λDNA特定位点产生有限数量切口的能力，从多变鱼腥藻中分离出了两种核酸内切酶，AvaI和AvaII。除了Mg2+之外，这两种酶都不需要辅助因子。核酸内切酶AvaI在噬菌体λ染色体上产生八个切口，其5'-末端序列为pPy-C-G-N。AvaII核酸内切酶对噬菌体λDNA的切割更为广泛，产生的片段其5'-末端序列为G-T-C-N或G-A-C-N。这两种酶都不会产生粘性末端。