35. Translation - definition, stages, mechanism.

Question 1

Definition - The process of transferring information from DNA to the mRNA, which is used as a template for protein synthesis is called translation

Answer 1

Definition - The process of transferring information from DNA to the mRNA, which is used as a template for protein synthesis is called translation

Question 2

Translation proceeds in the following phases:

Initiation:
- tRNA that carries the first amino acid is joined

• binding of tRNA to the complex is through recognition of the start codon - AUG in the mRNA by the anticodon in tRNA
• great amount of energy from ATP and GTP needed to create initiation complex

Answer 2

Translation proceeds in the following phases:

Initiation:
- tRNA that carries the first amino acid is joined

• binding of tRNA to the complex is through recognition of the start codon - AUG in the mRNA by the anticodon in tRNA
• great amount of energy from ATP and GTP needed to create initiation complex

Question 3

Elongation:

• the second tRNA whose anticodon corresponds to the second codon from mRNA and carries the corresponding amino acid enters the A site
• dipeptide is on second tRNA
• ribosome moves one codon right in direction 5’-3’
• released tRNA leaves the complex
• in the empty site enters a new aminoacryl - tRNA
• polypeptide chain continues to form as amino acids are added during elongation

Answer 3

Elongation:

• the second tRNA whose anticodon corresponds to the second codon from mRNA and carries the corresponding amino acid enters the A site
• dipeptide is on second tRNA
• ribosome moves one codon right in direction 5’-3’
• released tRNA leaves the complex
• in the empty site enters a new aminoacryl - tRNA
• polypeptide chain continues to form as amino acids are added during elongation

Question 4

Termination:

• one of the 3 termination codons moves into the A site
• release factors trigger the hydrolysis of the ester bond in peptidyl - tRNA and peptidyl transferase froms carboxyl end of the polypeptide chain
• complex dissociates

Answer 4

Termination:

• one of the 3 termination codons moves into the A site
• release factors trigger the hydrolysis of the ester bond in peptidyl - tRNA and peptidyl transferase froms carboxyl end of the polypeptide chain
• complex dissociates

Question 5

The first amino acid in prokaryotes is N-formylmethionine

In eukaryotes it’s methionine

Answer 5

The first amino acid in prokaryotes is N-formylmethionine

In eukaryotes it’s methionine