WK05 - Protein Structure

• Tertiary structure refers to the overall three-dimensional shape of a folded protein molecule.
• Secondary structures are formed by hydrogen bonds between peptide groups on different parts of the same polypeptide chain, resulting in alpha helices or beta pleated sheets.
• The primary structure is the sequence of amino acids that make up a protein.
• Quaternary structure is the arrangement of multiple polypeptides into one functional unit.
• The tertiary structure is stabilised by hydrogen bonds, disulphide bridges, ionic bonds and van der Waals forces
• Quaternary structure refers to the arrangement of multiple polypeptides into one large functional unit (protein)
• Disulfide bridges are covalent bonds between two sulfur atoms that form when there are two amino acids with thiol groups close together
• The primary sequence determines the secondary structure which then forms tertiary structure, leading to quaternary structure.
• Denaturation involves disrupting noncovalent interactions within a protein's secondary, tertiary, and quaternary structures.
• Ionic bonding occurs between positively charged side chains (arginine, lysine) and negatively charged side chains (aspartate, glutamate).
• Ionic bonds occur between positively charged side chains and negatively charged side chains.
• Proteins can be classified as fibrous proteins (keratin) or globular proteins (haemoglobin).