Proteins are made from long chains of amino acids
1. Monomers of proteins are amino acids
2. A dipeptide is formed when two amino acids join together.
3. Polypeptide formed when more than two amino acids join together.
4. Proteins are made up of one or more polypeptides
Different amino acids have different variable groups
- All amino acids have same general structure. Difference is variable group they contain.
Polypeptides are formed by condensation reactions
- Amino acids linked together by condensation reactions to form polypeptides. Molecule of water is released during reaction. Bonds form between amino acids is called peptide bonds. Reverse reaction happens during digestion.
Proteins have four structural levels
· Primary Structure – normal sequence of amino acids in the polypeptide chain
· Secondary Structure – polypeptide chain doesn’t remain flat and straight. Hydrogen bonds form between the amino acids. Makes it automatically fold into an alpha helix or fold into a beta pleated sheet