1 mRNA translation efficiency in a prokaryotic system is mainly determined by the complementary interaction of 16S rRNA and the mRNA region located upstream of the start codon of the gene. Blocks of purine residues in 16S rRNA interact with complementary pyrimidine nucleotides in mRNA (Shine–Dalgarno interactions; SD) . Contrary to prokaryotes, eukaryotic mRNAs usually lack SD elements. Translation initiation of most eukaryotic mRNAs proceeds by the ribosome scanning mechanism (hypothesized by Kozak [2, 3]). According to this model, the 40S ribosomal subunit binds to the cap structure on the 5'-terminus of mRNA, and then it scans the 5'-untranslated region (5'UTR) of mRNA until it reaches the initiator codon. Then, the 80S ribosome assembles, and polypeptide synthesis starts.