Yoo O J, Agarwal K L
J Biol Chem. 1980 Nov 25;255(22):10559-62.
Type II restriction endonucleases cleave duplex DNA at nucleotide sequences displaying 2-fold symmetry. Our data show that Msp I cleaves single strand oligonucleotides, d(G-A-A-C-C-G-G-A-G-A) and d(T-C-T-C-C-G-G-T-T) at 4 degrees, 25 degrees, and 37 degrees C reaction temperatures. The rate of cleavage of d(G-A-A-C-C-G-G-A-G-A) is several-fold faster than that of d(T-C-T-C-C-G-G-T-T). Single strand phi X174 DNA is also, cleaved by Msp I endonuclease giving well defined fragments. 5'-Nucleotide analysis of the fragments generated from single strand and replicating form DNA suggest that cleavage occurs at the recognition sequence d(C-C-G-G). The data show that Msp I endonuclease cleaves single strand oligonucleotides and prefers a recognition sequence surrounded by purine nucleotides. A general model for endonuclease cleavage of single strand and duplex DNA is presented.
II型限制性核酸内切酶在具有二重对称的核苷酸序列处切割双链DNA。我们的数据表明，Msp I在4℃、25℃和37℃的反应温度下切割单链寡核苷酸d(G-A-A-C-C-G-G-A-G-A)和d(T-C-T-C-C-G-G-T-T)。d(G-A-A-C-C-G-G-A-G-A)的切割速率比d(T-C-T-C-C-G-G-T-T)快几倍。单链φX174 DNA也被Msp I核酸内切酶切割，产生明确的片段。对单链和复制型DNA产生的片段进行5'-核苷酸分析表明，切割发生在识别序列d(C-C-G-G)处。数据表明，Msp I核酸内切酶切割单链寡核苷酸，并且偏爱被嘌呤核苷酸包围的识别序列。本文提出了一个核酸内切酶切割单链和双链DNA的通用模型。
