Protein metabolism

Which enzymes catabolise proteins?

Proteases

What two groups are proteases divided into?

1. Endopeptidases

2. Exopeptidases

What do endopeptidases do?

Cleave the internal peptide bonds of the substrate protein

Give for examples of endopeptiases

• Pepsin

• Trypsin

• Chimotrypsin

• Elastase

What do expopeptidases do?

Removes terminal amino acid of proteins

Carboxy peptidases remove C-terminal

Aminopeptidases remove N-terminal

Arrangement of protein metabolism

1. Endopeptidases first split the protein into smaller fragments

2. Further cleaved by exopeptidases until they form di- or tripeptides

3. These di- and tripeptides are then converted by fi- and tripeptidases

What can happen to the the released amino acids?

• Further metabolised

• Re-seed for synthesis of cellular proteins

Domination