Peptide Bond Formation and Peptidyl Transferase Reaction
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A peptide bond is an
A peptide bond is an amide type of covalent chemical bond linking two consecutive alpha-amino acids from C1 (carbon number one) of one alpha-amino acid and N2 (nitrogen number two) of another along a peptide or protein chain.
When two amino acids form a dipeptide through a peptide bond[1] it is a type of condensation reaction.[2] In this kind of condensation, two amino acids approach each other, with the non-side chain (C1) carboxylic acid moiety of one coming near the non-side chain (N2) amino moiety of the other. One loses a hydrogen and oxygen from its carboxyl group (COOH) and the other loses a hydrogen from its amino group (NH2). This reaction produces a molecule of water (H2O) and two amino acids joined by a peptide bond (-CO-NH-). The two joined amino acids are called a dipeptide.
The amide bond is synthesized when the carboxyl group of one amino acid molecule reacts with the amino group of the other amino acid molecule, causing the release of a molecule of water (H2O), hence the process is a dehydration synthesis reaction.
The peptidyl transferase is an aminoacyltransferase as well as the primary enzymatic function of the ribosome, which forms peptide bonds between adjacent amino acids using tRNAs during the translation process of protein biosynthesis. The substrates for the peptidyl transferase reaction are two tRNA molecules, one bearing the growing peptide chain and the other bearing the amino acid that will be added to the chain.
In Prokaryotes, the 50S (23S component) ribosome subunit contains the peptidyl transferase component and acts as a ribozyme. The peptidyl transferase center on the 50S subunit lies at the lower tips (acceptor ends) of the A- and O- site tRNAs.[1]:1062
In Eukaryotes, the 60S (28S component) ribosome subunit contains the peptidyl transferase component and acts as the ribozyme.
When two amino acids form a dipeptide through a peptide bond[1] it is a type of condensation reaction.[2] In this kind of condensation, two amino acids approach each other, with the non-side chain (C1) carboxylic acid moiety of one coming near the non-side chain (N2) amino moiety of the other. One loses a hydrogen and oxygen from its carboxyl group (COOH) and the other loses a hydrogen from its amino group (NH2). This reaction produces a molecule of water (H2O) and two amino acids joined by a peptide bond (-CO-NH-). The two joined amino acids are called a dipeptide.
The amide bond is synthesized when the carboxyl group of one amino acid molecule reacts with the amino group of the other amino acid molecule, causing the release of a molecule of water (H2O), hence the process is a dehydration synthesis reaction.
The peptidyl transferase is an aminoacyltransferase as well as the primary enzymatic function of the ribosome, which forms peptide bonds between adjacent amino acids using tRNAs during the translation process of protein biosynthesis. The substrates for the peptidyl transferase reaction are two tRNA molecules, one bearing the growing peptide chain and the other bearing the amino acid that will be added to the chain.
In Prokaryotes, the 50S (23S component) ribosome subunit contains the peptidyl transferase component and acts as a ribozyme. The peptidyl transferase center on the 50S subunit lies at the lower tips (acceptor ends) of the A- and O- site tRNAs.[1]:1062
In Eukaryotes, the 60S (28S component) ribosome subunit contains the peptidyl transferase component and acts as the ribozyme.
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