Amino Acid: Structure
Proteins
- Proteins are polymers (and macromolecules) made of monomers called amino acids
- The sequence, type and number of the amino acids within a protein determines its shape and therefore its function
- Proteins are extremely important in cells because they form all of the following:
- Enzymes
- Cell membrane proteins (eg. carrier)
- Hormones
- Immunoproteins (eg. immunoglobulins)
- Transport proteins (eg. haemoglobin)
- Structural proteins (eg. keratin, collagen)
- Contractile proteins (eg. myosin)
Amino acids
- Amino acids are the monomers of polypeptides
- There are 20 amino acids found in proteins common to all living organisms
- The general structure of all amino acids is a central carbon atom bonded to:
- An amine (also called amino) group -NH2
- A carboxylic acid group -COOH
- A hydrogen atom
- An R group (which is how each amino acid differs and why amino acid properties differ e.g. whether they are acidic or basic or whether they are polar or non-polar)
The general structure of an amino acid