Bernardi A, Maat J, de Waard A, Bernardi G
Eur J Biochem. 1976 Jun 15;66(1):175-9. doi: 10.1111/j.1432-1033.1976.tb10437.x.
Bacteriophage-T4-induced endonuclease IV suitable for DNA sequence analysis has been prepared by a modified and easily reproducible method. The specificity of T4-induced endonuclease IV has been investigated in order to verify whether this enzyme exhibits a single nucleotide recognition or a short sequence recognition. The 5'-terminal dinucleotides and 3'-terminal nucleotides of oligonucleotides released by T4-induced endonuclease IV from three single-stranded DNAs (from bacteriophages phiX174, fd, M 13) have been analysed. In different DNAs, 74-82% of the 5'-terminal dinucleotides end in 5'-deoxycytidylic acid; small but significant levels of several dinucleotides ending in 5'-deoxyadenylic acid, 5'-thymidylic acid and 5'-deoxyguanylic acid are also found. As far as 3'-terminal nucleotides are concerned all nucleotides are present with a large predominance of thymidylic acid. It is concluded that T4-induced endonuclease IV recognizes short nucleotide sequences like all other DNases investigated so far. The spectrum of such sequences is, however, very narrow.
已通过一种经过改进且易于重现的方法制备出适用于DNA序列分析的噬菌体T4诱导的核酸内切酶IV。为了验证该酶是表现出单核苷酸识别还是短序列识别，对T4诱导的核酸内切酶IV的特异性进行了研究。分析了T4诱导的核酸内切酶IV从三种单链DNA（来自噬菌体φX174、fd、M13）释放的寡核苷酸的5'端二核苷酸和3'端核苷酸。在不同的DNA中，74-82%的5'端二核苷酸以5'-脱氧胞苷酸结尾；还发现了少量但显著水平的几种以5'-脱氧腺苷酸、5'-胸苷酸和5'-脱氧鸟苷酸结尾的二核苷酸。就3'端核苷酸而言，所有核苷酸都存在，其中胸苷酸占主导地位。得出的结论是，T4诱导的核酸内切酶IV与迄今为止研究的所有其他DNA酶一样，识别短核苷酸序列。然而，此类序列的范围非常狭窄。
