Highland J H, Ochsner E, Gordon J, Bodley J W, Hasenbank R, Stöffler G
Proc Natl Acad Sci U S A. 1974 Mar;71(3):627-30. doi: 10.1073/pnas.71.3.627.
We previously showed that treatment of Escherichia coli ribosomes with antibodies specific for proteins L7 and L12 inhibits both EF-G.GDP binding and ribosome-dependent GTP hydrolysis (Highland et al. (1973) Proc. Nat. Acad. Sci. USA 70, 142-150; and Kischa et al. (1971) Nature New Biol. 233, 62-63). We now report that antibodies to six additional proteins also inhibit GTP hydrolysis, but do not inhibit EF-G.GDP binding. Moreover, inhibition by these antibodies is dependent on the state of association of the treated ribosomes. When 70S couples are treated, only antibodies to proteins L14 and L23 are inhibitory and then only partially. However, when separated ribosomal subunits are treated individually and then mixed with the complementary untreated subunits, inhibition by antibodies L14 and L23 is complete, and antibodies to proteins L19, L27, S9, and S11 now show an inhibitory effect. In addition, treatment of subunits with any of these six antibodies (but not those to L7 or L12) results in inhibition of reassociation, which is presumably responsible for the inhibition of hydrolysis. These data suggest that the area of interaction between EF-G and the ribosome is restricted to proteins L7 and L12, and that antibodies to proteins L14, L19, L23, L27, S9, and S11, but not L7 and L12, block the physical association of the subunits.
我们先前表明，用针对蛋白质L7和L12的特异性抗体处理大肠杆菌核糖体，会抑制EF-G.GDP结合以及核糖体依赖性GTP水解（Highland等人，(1973)《美国国家科学院院刊》70, 142 - 150；以及Kischa等人，(1971)《自然新生物学》233, 62 - 63）。我们现在报告，针对另外六种蛋白质的抗体也抑制GTP水解，但不抑制EF-G.GDP结合。此外，这些抗体的抑制作用取决于被处理核糖体的结合状态。当处理70S核糖体对时，只有针对蛋白质L14和L23的抗体具有抑制作用，且只是部分抑制。然而，当分别处理分离的核糖体亚基，然后与互补的未处理亚基混合时，L14和L23抗体的抑制作用是完全的，并且针对蛋白质L19、L27、S9和S11的抗体现在也显示出抑制作用。此外，用这六种抗体中的任何一种（但不是针对L7或L12的抗体）处理亚基会导致再结合受到抑制，这可能是水解受到抑制的原因。这些数据表明，EF-G与核糖体之间的相互作用区域仅限于蛋白质L7和L12，并且针对蛋白质L14、L19、L23、L27、S9和S11的抗体（而不是L7和L12的抗体）会阻止亚基的物理结合。
