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Catalytic Activity of the Ribosome

Ribosomes are cell organelles responsible for assembling protein. They receive assembling protein blueprints from messenger ribonucleic acid (mRNA). Without ribosomes, protein synthesis wouldn't occur and the basic functions of life wouldn't be possible. Catalytic activity in ribosomes is fairly simple to understand. In a nutshell, ribosomes catalytic activity is the transfer of activated amino acids into complex peptide chains to form essential proteins.

Basic Function of Ribosomes
- The basic function and catalytic activity of ribosomes is called translation. This is defined as the activity of reading information transmitted by mRNA, using it to create amino acids, the building block of protein, and then organizing the amino acids into a complex protein. Amino acids are attached to transfer RNA (tRNA) that binds amino acids together. Completed proteins are sent to the Golgi apparatus, which directs the protein to where it's needed in the cell and exports surplus out of the cell.
Structure
- Ribosomes are structured into two main units -- the large subunit and the small subunit. The large subunit is the active site of ribosomes where new peptide chains are formed once protein is synthesized. It's made up of two strands of RNA, one long and one short. New proteins bind on these two strands to form peptide chains. The enzyme that's used to catalyze this synthesis is an adenine RNA nucleotide. The small subunit is the site that controls information flow during protein synthesis. It's responsible for pairing mRNA with tRNA and then sending the pair to the large subunit.
Initiation of Catalytic Activity
- Translation begins when ribosomes allow an mRNA molecule to enter the small subunit through a needle-like hole that directs it for decoding. Here, the mRNA is paired with the tRNA, which carries an enzyme called methionine. Methionine attracts the mRNA to bind together with the tRNA in a triple-coded bond. Once bound, the tRNA carries the mRNA to the large subunit for further protein synthesis.
Elongation of Catalytic Activity
- At a bonding site in the large subunit, the mRNA attracts a Proline that carries a complementary triple-coded unit of amino acid. The amino acid is bound to the mRNA, at which point the tRNA is disconnected. Both bonding sites produce mRNA-bound amino acids simultaneously. When released, the two amino acids bind together as instructed by the mRNA to form a peptide chain. Here the amino acids are synthesized into protein strands. Once the protein strands are elongated to the appropriate size, they're released from the large subunit and directed to the Golgi apparatus, which is called termination.

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