Studies on the Formation of Transfer Ribonucleic Acid-Ribosome Complexes
Year: 1966
Type: article
Abstract: Streptomycin-sensitive 70S ribosomes which are dissociated into 50S and 30S particles by dialysis against 1 x 10-4 m magnesium acetate, and then reassociated in 0.02 m magnesium acetate, differ from nondissociated 70S ribosomes in 14C-aminoacyl soluble ribonucleic acid (sRNA) binding. 1. Reassociated ribosomes bind about twice as much 14C-phenylalanyl-sRNA in the presence of polyuridylic acid as nondissociated ribosomes. 2. 14C-Phenylalanyl-sRNA binding to reassociated ribosomes in the presence of polyuridylic acid is reduced 50% by streptomycin; this binding to nondissociated ribosomes is only slightly affected by streptomycin. 3. Streptomycin can inhibit 14C-isoleucyl-sRNA binding to reassociated ribosomes in the presence of polyuridylic acid, but stimulates this binding to nondissociated ribosomes. These effects are greatly influenced by the sRNA-ribosome ratio. Shearing 70S ribosomes by passage through a micropipette also produces Reactions 2 and 3 above, but not Reaction 1. The results indicate that various treatments of the ribosomes (dissociation, shearing) and sRNA to ribosome ratios modify the effects of streptomycin on 14C-aminoacyl-sRNA binding to ribosomes. In addition, the data suggest that different mechanisms may be involved in the effects of streptomycin on inhibiting protein synthesis and on stimulating ambiguous codon recognitions.
Source: Journal of Biological Chemistry
Author: Sidney Pestka
Institution: National Institutes of Health
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,430
OpenAlex ID: W1587042049