Initiation of bacterial protein synthesis with wild type and mutated variants of initiation factor 2

Abstract

In-frame translation of code triplets (codons) of mRNAs into the peptide chains that define the cell’s proteome requires accurate positioning of the mRNA start codon in the ribosomal P site during initiation of protein synthesis. Initiation in bacteria begins on the small (30S) ribosomal subunit. It is generated through dissociation of the bacterial ribosome into its small and large (50S) subunits. Ribosome dissociation is promoted by ribosomal recycling factor, RRF, and elongation factor G (EF-G) (Pavlov et al., 1997; Karimi et al., 1999; Peske et al., 2005; Pavlov et al., 2008; Savelsbergh et al., 2009) following termination of protein synthesis by a class-1 release factor (RF1/2) (Freistroffer et al., 2000) and RF1/2 recycling by the G-protein RF3 (Freistroffer et al., 1997; Zavialov et al., 2001).