Whitehead P R, Jacobs D, Brown N L
Nucleic Acids Res. 1986 Sep 11;14(17):7031-45. doi: 10.1093/nar/14.17.7031.
We describe the partial purification and characterisation of five Type II restriction endonucleases from two strains of Herpetosiphon giganteus. One of the activities, HgiJII, was the first enzyme found that cleaves DNA at the family of related sequences 5'-G-R-G-C-Y/C-3'. This enzyme may be related to the enzyme HgiAI from a different strain of the same species, and which cleaves at the sites 5'-G-W-G-C-W/C-3'. We have shown that DNAs from the strains producing HgiAI and HgiJII are resistant to both of these restriction endonucleases. The remaining four enzymes described here share recognition and cleavage specificities with other restriction endonucleases. The evolution of Type II restriction-modification systems and their role in vivo are discussed.
我们描述了从两株巨大管孢藻中部分纯化和鉴定出的五种II型限制性内切酶。其中一种活性酶HgiJII是首次发现的能在相关序列家族5'-G-R-G-C-Y/C-3'处切割DNA的酶。该酶可能与来自同一物种不同菌株的HgiAI酶相关，HgiAI酶在5'-G-W-G-C-W/C-3'位点切割。我们已经表明，产生HgiAI和HgiJII的菌株的DNA对这两种限制性内切酶均具有抗性。这里描述的其余四种酶与其他限制性内切酶具有相同的识别和切割特异性。文中讨论了II型限制修饰系统的进化及其在体内的作用。
