Lautenberger J A, White C T, Haigwood N L, Edgell M H, Hutchison C A
Gene. 1980 May;9(3-4):213-31. doi: 10.1016/0378-1119(90)90324-k.
The Type II restriction endonuclease BglI recognizes the interrupted DNA sequence 5'-G-C-C-N-N-N-N-N-G-G-C-. This sequence occurs at all locations in over 33 000 base pairs of DNA sequence where the enzyme was found to cut DNA and nowhere else. All six of the specified bases are essential parts of the site since all groups of five of the six bases occur in the DNA sequences tested and none of them are cut by BglI. The length of the block of intervening unspecified positions must be exactly five since all other sizes between zero and 15 occur in the DNA sequences searched and none are cut by BglI. The 5'-terminal nucleotides of BglI cleaved phage G4 replicative form DNA and plasmid pER18 DNA were compared with the DNA sequences near the BglI sites on these DNAs. These results indicated that BglI cuts within the intervening unspecified region and produces single-stranded 3' termini that are three bases long. The BglI recognition site and cleavage points can thus be represented as follows: (Formula: see text). This study of the BglI recognition site was facilitated by the use of inexpensive microcomputers. A system of programs was developed that allowed analysis of over 33 kb of DNA sequences stored on flexible magnetic disks or audio cassettes. While these programs were generally written in the higher level language BASIC, some assembly language subroutines were utilized to reduce execution time.
II型限制性内切酶BglI识别间断的DNA序列5'-G-C-C-N-N-N-N-N-G-G-C-。在发现该酶可切割DNA的超过33000个碱基对的DNA序列中的所有位置都存在此序列，其他位置则没有。指定的六个碱基都是该位点的必需部分，因为在测试的DNA序列中出现了六个碱基中的所有五个碱基组合，且它们都不会被BglI切割。中间未指定位置的片段长度必须恰好为五个，因为在搜索的DNA序列中出现了从零到15的所有其他长度，且它们都不会被BglI切割。将BglI切割的噬菌体G4复制型DNA和质粒pER18 DNA的5'-末端核苷酸与这些DNA上BglI位点附近的DNA序列进行了比较。这些结果表明，BglI在中间未指定区域内切割，并产生三个碱基长的单链3'末端。因此，BglI识别位点和切割点可表示如下：（公式：见正文）。使用廉价的微型计算机有助于对BglI识别位点进行这项研究。开发了一个程序系统，可对存储在软盘或盒式录音带上的超过33 kb的DNA序列进行分析。虽然这些程序通常是用高级语言BASIC编写的，但也使用了一些汇编语言子程序来减少执行时间。
