Maĭmets T O, Ustav M B, Remme Ia L, Villems R L
Mol Biol (Mosk). 1984 Nov-Dec;18(6):1597-605.
We show that Escherichia coli 50S ribosomal subunits depleted of protein L16 can nevertheless catalyze the transfer of the peptide moiety from fMet-tRNA to puromycin, being, however, unable to use a fragment CACCA-Phe as an acceptor substrate. On the other hand, we found that protein L16 as well as its large fragment (amino acids 10-136) both interact with tRNA in solution (Kd approximately 10(-7) M). Moreover, L16 interacts with CACCA-Phe in solution as well as protects 3' end of tRNA from the enzymatic degradation. We suggest that L16, although not being the peptidyl transferase as such, is involved in the binding of the 3' end cytidines of tRNA into the ribosomal A site.
我们发现，缺乏蛋白质L16的大肠杆菌50S核糖体亚基仍能催化肽部分从fMet-tRNA转移至嘌呤霉素，然而，它无法将片段CACCA-Phe用作受体底物。另一方面，我们发现蛋白质L16及其大片段（氨基酸10 - 136）在溶液中均与tRNA相互作用（解离常数Kd约为10⁻⁷ M）。此外，L16在溶液中与CACCA-Phe相互作用，并保护tRNA的3'端不被酶促降解。我们认为，L16虽然本身不是肽基转移酶，但参与了tRNA 3'端胞嘧啶与核糖体A位点的结合。
