Figure 5.

Induced‐fit model of stop codon recognition by class I RFs. Initial binding of closed RF to cognate stop codon in A site (k _on) is followed by a ribosome‐induced conformational change (k _conf) into the higher affinity open conformation (k _off2 ≪ k _off1). This active conformation of RF then catalyzes the hydrolysis of the nascent peptide from the P‐site tRNA (k _hydr), releasing the peptide from the ribosome (k _diss). The experimentally measured peptide release rate (k _release) is dependent on k _conf, k _hydr, and k _diss.