2.4 - A - Amino Acids
Polypeptides (aka proteins) are polymer biomolecules that are formed when amino acids monomers link together via condensation reactions.
Each amino acid consists of a central carbon atom that is covalently bound to four things:
When condensation occur between these molecules, they form a peptide bond. and water molecule is produced. When several link together, they form a polypeptide.
Some proteins contain amino acids that are not included in the basic 20. This is typically due to amino acids being modified after protein synthesis. A standard of this is collagen, a structural protein. At many instances, proline groups are converted to hydroxyproline which makes it more stable.
Drawing Peptide Bond Formation (S1)
The chart below shows the 20 amino acids and their structures. Note that each has the same basic components, but only the R group changes (shaded in each diagram). You should be able to use these to show how amino acids will condense to form peptide bonds and polypeptides. Choose 4 amino acids and show how they can be linked. Your diagram should include the reactants, the waste molecules and the final product. Inside the cell, these polypeptides are synthesized by the ribsome (see here).