The entire mechanism of protein synthesis in eukaryotes is generally the same as in prokaryotes, with three phases explained as termination, elongation and initiation. Furthermore, there are some significant differences, mainly in during initiation.
? Whereas a prokaryotic ribosome has a sedimentation coefficient of 70S and subunits of 50S and 30S, a eukaryotic ribosome has a sedimentation coefficient of 80S with subunits of 60S and 40S. The composition of eukaryotic ribosomal subunits is also more difficult than prokaryotic subunits but the function of every subunit is essentially the similar as in prokaryotes.
? In eukaryotes, each mRNA is monocistronic which is, discounting any subsequent post-translational cleavage reactions which should happen the mRNA encodes a one protein. In prokaryotes, various mRNAs are polycistronic which is they encode many proteins. every coding sequence in a prokaryotic mRNA has its own termination and initiation codons.
? Starting of the protein synthesis in eukaryotes needs at least nine distinct eukaryotic initiation factors (eIFs) compared with the three initiation factors (IFs) in prokaryotes.
? In the eukaryotes, initiating amino acid is methionine isnot N-formylmethionine as in prokaryotes.