Practice question

Post-termination complexes contain deacylated tRNA and mRNA still bound to 70S ribosomes and require active disassembly for new elongation cycles. In bacteria, ribosome recycling factor RRF, a near-perfect tRNA shape mimic composed of helical bundle and domain resembling anticodon arm, binds to the A-site together with EF-G-GTP. GTP hydrolysis induces subunit rotation and splitting into 30S and 50S subunits, after which IF3 promotes tRNA dissociation and prevents reassociation, freeing subunits for initiation. EF-Tu functions only during elongation delivery, while eukaryotic homologs handle recycling differently, requiring no bacterial-type RRF protein machinery.