Free energy periodicity in E.coli

It has been seen that sequences upstream from coding regions tend to possess significant complementarity to the exposed part of the 16S rRNA in E.coli. While upstream binding between the Shine-Dalgarno sequence and the mRNA may be a necessary condition for translation, it appears to be insufficient. By computing the free energy binding within the coding sequence, it is suggested that the 16S has a continuing role through elongation of translation as well.