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Effect of Nascent Peptide Steric Bulk on Elongation Kinetics in the Ribosome Exit Tunnel.

ABSTRACT: All proteins are synthesized by the ribosome, a macromolecular complex that accomplishes the life-sustaining tasks of faithfully decoding mRNA and catalyzing peptide bond formation at the peptidyl transferase center (PTC). The ribosome has evolved an exit tunnel to host the elongating new peptide, protect it from proteolytic digestion, and guide its emergence. It is here that the nascent chain begins to fold. This folding process depends on the rate of translation at the PTC. We report here that besides PTC events, translation kinetics depend on steric constraints on nascent peptide side chains and that confined movements of cramped side chains within and through the tunnel fine-tune elongation rates.

SUBMITTER: Po P

PROVIDER: S-EPMC5511029 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Effect of Nascent Peptide Steric Bulk on Elongation Kinetics in the Ribosome Exit Tunnel.

Po Pengse P Delaney Erin E Gamper Howard H Szantai-Kis D Miklos DM Speight Lee L Tu LiWei L Kosolapov Andrey A Petersson E James EJ Hou Ya-Ming YM Deutsch Carol C

Journal of molecular biology 20170505 12

All proteins are synthesized by the ribosome, a macromolecular complex that accomplishes the life-sustaining tasks of faithfully decoding mRNA and catalyzing peptide bond formation at the peptidyl transferase center (PTC). The ribosome has evolved an exit tunnel to host the elongating new peptide, protect it from proteolytic digestion, and guide its emergence. It is here that the nascent chain begins to fold. This folding process depends on the rate of translation at the PTC. We report here that ...[more]

PMID: 28483649

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