Proteins are polymers of Amino Acids, so are macromolecules. Some contain 100s of amino acids some contains several thousand.
- Structure of plasma membranes
- Immune system
- Structure of chromosomes
Amino acids are built around a carbon atom which is attached to:
- a hydrogen atom
- an amino group (-NH2)
- a carboxyl group (-COOH)
- An 'R' group which determines the nature of the amino acid. The 'R' represents other atoms in the molecule.
Two amino acids joined together are known as a dipeptide, and many are polypeptides. When two or more peptide chains join to make a dipeptide or a polypeptide chain, a condensation reaction occurs. When they are broke apart, it is hydrolysis.
Proteins Overview Part 2
- Specific sequence of amino acids.
- B-pleated sheet
- Held in place by hydrogen bonds
- Further 'folding' to give a 3D shape.
- Held by hydrogen bonds between R-group and amino acids.
- Held by Disulphide Bridges between amino acids and R-groups containing sulphur.
- Held by ionic bonds between amino acids and positively/negatively charged R-groups.
- Two or more polypeptide chains e.g haemonglobin (globular), collagen (fibrous).