Burma D P, Tewari D S, Srivastava A K
Arch Biochem Biophys. 1985 Jun;239(2):427-35. doi: 10.1016/0003-9861(85)90708-8.
It has been demonstrated in this laboratory that 16 S and 23 S RNAs form a binary complex like 30 S and 50 S ribosomes under certain specific conditions, and 5 S RNA can be incorporated into the complex in stoichiometric amounts in presence of three ribosomal proteins, L5, L18, and L15/25. These studies raised the basic question of whether such complex will have biological activity. Therefore, the following steps in protein synthesis were examined with the complex in place of the ribosomes: (i) poly-U-dependent binding of phenylalanyl tRNA; (ii) EF-G-dependent GTPase activity; (iii) initiation complex formation; (iv) peptidyl transferase activity; and (v) poly-U-dependent polyphenylalanine synthesis. All the steps could be unequivocally demonstrated by the addition of a limited number of proteins although the complex had comparatively much less activity than 70 S ribosomes. It appears that rRNAs are directly involved in various steps of protein synthesis. Furthermore, the 16 S.23 S RNA complex might have acted as a primitive ribosome, as suggested by Crick and Orgel.
本实验室已证明，在某些特定条件下，16S和23S RNA会形成类似30S和50S核糖体的二元复合物，并且在三种核糖体蛋白L5、L18和L15/25存在的情况下，5S RNA能够以化学计量的量掺入该复合物中。这些研究提出了一个基本问题，即这种复合物是否具有生物活性。因此，使用该复合物替代核糖体，对蛋白质合成中的以下步骤进行了检测：（i）苯丙氨酰tRNA的多聚-U依赖性结合；（ii）EF-G依赖性GTP酶活性；（iii）起始复合物形成；（iv）肽基转移酶活性；以及（v）多聚-U依赖性多聚苯丙氨酸合成。尽管该复合物的活性比70S核糖体低得多，但通过添加有限数量的蛋白质，所有这些步骤都能得到明确证明。似乎rRNA直接参与了蛋白质合成的各个步骤。此外，正如克里克和奥格尔所指出的，16S·23S RNA复合物可能起到了原始核糖体的作用。
