Sommer A, Etchison J R, Gavino G, Zecherle N, Casiano C, Traut R R
J Biol Chem. 1985 Jun 10;260(11):6522-7.
Two monoclonal antibodies with specificities for Escherichia coli 50 S ribosomal subunit protein L7/L12 were isolated. The antibodies and Fab fragments thereof were purified by affinity chromatography using solid-phase coupled L7/L12 protein as the immunoadsorbent. The two antibodies were shown to recognize different epitopes; one in the N-terminal and the other in the C-terminal domain of protein L7/L12. Both intact antibodies strongly inhibited polyuridylic acid-directed polyphenylalanine synthesis, ribosome-dependent GTPase activity, and the binding of elongation factor EF-G to the ribosome. Ratios of antibody to ribosome of 4:1 or less were effective in inhibiting these activities. Neither antibody prevented the association of ribosomal subunits to form 70 S ribosomes. The Fab fragments showed similar effects.
分离出了两种对大肠杆菌50S核糖体亚基蛋白L7/L12具有特异性的单克隆抗体。使用固相偶联的L7/L12蛋白作为免疫吸附剂，通过亲和层析法纯化了这些抗体及其Fab片段。结果表明，这两种抗体识别不同的表位；一个在蛋白L7/L12的N端结构域，另一个在C端结构域。两种完整抗体均强烈抑制聚尿苷酸指导的聚苯丙氨酸合成、核糖体依赖性GTP酶活性以及延伸因子EF-G与核糖体的结合。抗体与核糖体的比例为4:1或更低时可有效抑制这些活性。两种抗体均未阻止核糖体亚基缔合形成70S核糖体。Fab片段显示出类似的效果。
