Translation enhancement by optimized downstream box sequences in Escherichia coli and Mycobacterium smegmatis.

The effect on translation of downstream box sequences optimized for binding to Mycobacterium smegmatis and Escherichia coli 16S rRNA in the absence of a Shine-Dalgarno (SD) region was investigated. The relative translational efficiency of each construct in either M. smegmatis or E. coli was determined. Eradication of the SD region in the absence of a downstream box abolished the translation activity. In contrast, optimized downstream box constructs resulted in a 13- and 18-fold increase in protein synthesis, relative to non-optimized DB controls in E. coli and M. smegmatis, respectively.