Gimautdinova O I, Karpova G G, Knorre D G, Kobetz N D
Nucleic Acids Res. 1981 Jul 24;9(14):3465-81. doi: 10.1093/nar/9.14.3465.
Oligo(U) derivatives with [14C]-4-(N-2-chloroethyl-N-methylamino)benzaldehyde attached to 3'-end cis-diol group via acetal bond, p(Up)n-1UCHRCl as well as with [14C]-4-(N-2-chloroethyl-N-methylamino)benzylamine attached to 5'-phosphate via amide bond, ClRCH2NHpU(pU)6 were used to modify 70S E. coli ribosomes near mRNA binding centre. Within ternary complex with ribosome and tRNAPhe all reagents covalently bind to ribosome the extent of modification being 0.1-0.4 mole/mole 70S. p(Up)n-1UCHRCl alkylates either 30S (n=5,7) or both subunits (n=6,8). rRNA is preferentially modified within 30S subunit. ClRCH2NHpU(pU)6 alkylates both subunits the proteins being mainly modified. The distribution of the label among proteins differ for various reagents. S4, S5, S7, S9, S11, S13, S15, S18 and S21 are found to be alkylated within 30S subunit, proteins L1, L2, L6, L7/L12, L19, L31 and L32 are modified in the 50S subunit. Most proteins modified within 30S subunit are located at the "head" of this subunit and proteins modified within 50S subunit are located at the surface of the contact between this subunit and the "head" of 30S subunit at the model of Stoffler.
通过缩醛键将带有[¹⁴C]-4-(N-2-氯乙基-N-甲基氨基)苯甲醛连接到3'-末端顺式二醇基团的寡聚(U)衍生物，即p(Up)ₙ₋₁UCHRCl，以及通过酰胺键将带有[¹⁴C]-4-(N-2-氯乙基-N-甲基氨基)苄胺连接到5'-磷酸基团的化合物，即ClRCH₂NHpU(pU)₆，被用于在mRNA结合中心附近修饰70S大肠杆菌核糖体。在与核糖体和苯丙氨酰-tRNA形成的三元复合物中，所有试剂都与核糖体共价结合，修饰程度为0.1 - 0.4摩尔/摩尔70S。p(Up)ₙ₋₁UCHRCl使30S亚基（n = 5,7）或两个亚基（n = 6,8）烷基化。rRNA在30S亚基内优先被修饰。ClRCH₂NHpU(pU)₆使两个亚基烷基化，主要修饰蛋白质。不同试剂在蛋白质中的标记分布不同。发现S4、S5、S7、S9、S11、S13、S15、S18和S21在30S亚基内被烷基化，蛋白质L1、L2、L6、L7/L12、L19、L31和L32在50S亚基中被修饰。在30S亚基内修饰的大多数蛋白质位于该亚基的“头部”，而在50S亚基内修饰的蛋白质位于根据施托弗勒模型该亚基与30S亚基“头部”之间的接触表面。
