Fig 4. The mRNA shapes of the native bR, SRII, chimeric protein SR1-8bRΔ(0–9), and optimized bR gene.
The region (-4, +47) with numbering starting from ATG start codon is shown. This region corresponds to amino acids from Met0 to Leu15. Free energies presented are expressed in kcal/mol. The values of mRNA free energy for SRII and SR1-8bRΔ(0–9) are considerably smaller than those of the native bR gene. The mRNA structure optimization of bR by silent mutations increased the free energy of the region (-4, +47) by 6.2 kcal/mol. The red arrows indicate the mutated nucleotides.