AAT Bioquest

What are the differences between Protein Synthesis in Prokaryotes and Eukaryotes?

Posted February 24, 2023


Basis of differentiation

Prokaryotic Protein Synthesis

Eukaryotic Protein Synthesis

mRNA molecules 

mRNA molecules are polycistronic and contain the coding sequences of several genes in a metabolic pathway 

mRNA molecules are monocistronic and contain the coding sequence of only one peptide 


Neither splicing nor processing of the mRNA transcript occurs

The main mRNA transcript goes through processing and splicing to form a functional mRNA molecule

Presence of introns

Do not contain introns and only contain exons

Most of the genes contain introns as well as exons, the exons are joined together and introns become removed during mRNA processing

First methionine 

The first methionine entering the ribosome is formylated into N formyl methionine

The methionine entering the ribosome is not formylated 

Initiating factors

Its initiating factor are PIF-1, PIF-2, and PIF-3

Its initiating factors are eIF1-6, eIF4B, EIF4C,EIF4D, EIF4F

Where translation begins

Translation begins at the AUG codon

Translation begins through the 5’ cap binding the mRNA to the ribosomal unit at the first AUG codon

Transcription/translation events

Translation and transcription occurs simultaneously

Transcription occurs first and translation occurs subsequently 

mRNA formation

Bacterial mRNA formation does not include the addition of a cap and poly A tail (except in archaebacteria) 

mRNA formation includes the addition of a 5’ cap and poly A tail (of approximately 200 adenine nucleotides) at the 3’ end of a mRNA transcript 

Additional resources

From RNA to Protein

ReadiUse™ TCA Deproteinization Sample Preparation Kit