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Schlagwörter:
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Zusammenfassung:
Elongation factor P (EF-P) is a translation factor of unknown function that has been implicated
in a great variety of cellular processes. Here, we show that EF-P prevents ribosome from stalling
during synthesis of proteins containing consecutive prolines, such as PPG, PPP, or longer proline
strings, in natural and engineered model proteins. EF-P promotes peptide-bond formation and
stabilizes the peptidyl–transfer RNA in the catalytic center of the ribosome. EF-P is posttranslationally
modified by a hydroxylated b-lysine attached to a lysine residue. The modification enhances the
catalytic proficiency of the factor mainly by increasing its affinity to the ribosome. We propose
that EF-P and its eukaryotic homolog, eIF5A, are essential for the synthesis of a subset of proteins
containing proline stretches in all cells.