{'fraction_non_alphanumeric': 0.045824847250509164, 'fraction_numerical': 0.020366598778004074, 'mean_word_length': 4.553672316384181, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Accumulation of tRNAMetf on 80-S ribosomes in vitro under the influence of a Met-tRNA deacylase from rat-liver microsomes.

A Met-tRNA deacylase has been partially purified from the 0.5 M KCl wash of rat liver microsomes. In preparative sucrose gradients, the active component sediments as a single band at about 6 S, corresponding to an estimated molecular weight of 1.7 X 10(5). The deacylase is specific for Met-tRNA, without discriminating between Met-tRNA f and Met-tRNAm. Met-tRNAf bound to the initiation factor IF-MP in the ternary complex, IF-MP-GTP-Met-tRNAf, or to initiation-factor-dependent, complexes with 40-S subunits or 80-S ribosomes, is protected against deacylation. However, in the course of the initiation-factor-dependent joining of the 40-S subunit complex to 60-S ribosomal subunits, the bound Met-tRNAf is exposed to added deacylase. Under these conditions, deacylation is inhibited by GTP. The tRNAMetf remains bound and accumulates on the 80-S ribosomes.