Effect of ribosome binding site on gene expression in Escherichia coli

Using the expression of human renin gene in Escherichia coli as a model, we have observed that a distance of 7-10 nucleotides between the Shine-Dalgarno site to the initiation codon ATG is optimal for translation initiation. The sequence ATA as the triplet preceding the ATG gives the best expression among those tested. These observations agree with the statistical bias observed for the genes of E. coli and its phages. We have also compared gene expression with three different Shine-Dalgarno sites. Expression of a given gene can be increased by as much as 1000-fold with slight modifications in the Shine-Dalgarno sequence.