Measurements of translation initiation from all 64 codons inE. coli

Abstract

ABSTRACTOur understanding of translation is one cornerstone of molecular biology that underpins our capacity to engineer living matter. The canonical start codon (AUG) and a few near-cognates (GUG, UUG) are typically considered as the “start codons” for translation initiation inEscherichia coli(E. coli). Translation is typically not thought to initiate from the 61 remaining codons. Here, we systematically quantified translation initiation inE. colifrom all 64 triplet codons. We detected protein synthesis above background initiating from at least 46 codons. Translation initiated from these non-canonical start codons at levels ranging from 0.01% to 2% relative to AUG. Translation initiation from non-canonical start codons may contribute to the synthesis of peptides in both natural and synthetic biological systems