REVERSIBLE CHEMICAL MODIFICATION OF URACIL THYMINE AND GUANINE NUCLEOTIDES AND MODIFICATION OF ACTION OF RIBONUCLEASE ON RIBONUCLEIC ACID
REVERSIBLE CHEMICAL MODIFICATION OF URACIL THYMINE AND GUANINE NUCLEOTIDES AND MODIFICATION OF ACTION OF RIBONUCLEASE ON RIBONUCLEIC ACID
复制标题
DOI：
10.1021/bi00864a002
复制
发表时间：
1967-01-01
期刊：
影响因子：
2.9
通讯作者：
GILHAM, PT
中科院分区：
文献类型：
--
作者：
HO, NWY;GILHAM, PT
Undine、Undine 5[image]-磷酸、胸苷5 [image]-磷酸、鸟苷5[image]-磷酸和脱氧鸟苷5[image]-磷酸与N-环己基-N[image]-[beta]-（4-甲基吗啉基-hexamethyl）碳二亚胺对甲苯磺酸盐在pH 8-8.5的水中反应，在这些条件下，与腺苷或胞苷衍生物没有可检测的反应。反应的产物是含有1分子的卡波酰胺试剂连接到核苷酸的碱基的加合物，并且在嘧啶衍生物的情况下，提出了N3-取代的结构。通过在pH 10-11下处理，可以容易地从衍生物中除去碳二酰胺基团。UNDINE化合物的可逆阻断程序用于对胰腺RNA酶的作用施加更大的特异性。尿苷酰-（3[image]-5[image]）-undine和尿苷酰-（3[image]-5[image]）-cytidine在用上述试剂处理后均对RNase降解具有抗性。开发了一种程序，通过该程序可以仅在胞苷3[image]-磷酰基位置切割RNA。在该方法中，首先用上述试剂处理RNA，然后用RNase水解。随后除去或破坏酶，并除去封闭基团。对产物的分析表明，RNA中由undine 3[image]-磷酰基键裂解产生的那些组分被降低到低水平。
Undine, undine 5[image]-phosphate, thymidme 5[image]-phosphate, guanosine 5[image]-phosphate, and deoxy-guanosine 5[image]-phosphate react with N-cyclohexyl-N[image]-[beta]-(4-methylmorpho-hnium)ethylcarbodiimide p-toluenesulfonate in water at pH 8-8.5 and, under these conditions, there is no detectable reaction with adenosine or cytidine derivatives. The products of the reaction are adducts containing 1 molecule of the carbodumide reagent attached to the base of the nucleotide and, in the case of the pyrimidine derivatives, an N3-substituted structure is proposed. The carbodumide groups can be readily removed from the derivatives by treatment at pH 10-11. The reversible blocking procedure for undine compounds was used to impose greater specificity on the action of pancreatic RNase. Uridylyl-(3[image]-5[image])-undine and uridylyl-(3[image]-5[image])-cytidine are both resistant to RNase degradation after they have been treated with the above reagent. A procedure was developed by which RNA may be cleaved at the cytidine 3[image]-phosphoryl positions only. In this procedure RNA is 1st treated with the above reagent and then hydrolyzed with RNase. The enzyme is subsequently removed or destroyed and the blocking groups are removed. The analysis of the products shows that those components which arise from cleavage at undine 3[image]-phosphoryl bonds in the RNA were reduced to a low level.