Lecture #7: Protein 2^o, 3^o and 4^o structure

Read: pg. 125-158 (structure)

Optional: Pg. 107-115 (sequencing; may be helpful in doing problems)

HW (Due Monday, September 25, at end of class)

• Pg. 122 (4, 8, 12)
• Pg. 159 (1, 5, 6, 9)

1. Understand peptide bonds.
2. Understand subunit composition of proteins and the types of bonds that are disrupted by SDS (a detergent) and mercaptoethanol.
3. Understand how cleavage cleavage of peptide bonds with CNBr or proteases (such as trypsin and chymotrypsin) are used to determine amino acid sequence of proteins.
4. Recognize and predict secondary structure (a -helix and b -pleated sheets) of proteins.
5. Identify the types of bonds and forces that determine 2^o, 3^o and 4^o structure.
6. Describe energy and entropy changes that occur during protein folding.