1. Fundamentals of Biochemistry Third Edition Fundamentals of Biochemistry Third Edition Chapter 4 Amino Acids Chapter 4 Amino Acids Copyright © 2008 by John Wiley & Sons, Inc. Donald Voet Judith G. Voet Charlotte W. Pratt

3. Section 1 – Amino Acid Structure

4. zwitterions

9. Titration of Glycine pI – isoelectic point of an amino acid or protein. The pH at which a protein or amino acid has no net charge.

12. Formation of Peptide bond H2OH2O

13. A W D G

15. Two representations of an amino acid at neutral pH (b) Ball-and stick model (a) Structure

16. Stereochemistry Stereoisomers - compounds that have the same molecular formula but differ in the arrangement of atoms in space Enantiomers - nonsuperimposable mirror images Chiral carbons - have four different groups attached RS – nomenclature is not used for amino acids LD – nomenclature used for amino acids

17. L=levo: rotates polarized light to the left D=dextro: rotates polarized light to the right

21. Section 3 – Amino Acid Derivatives

22. Aequorea victoria

23. Practice: Questions: 1, 3 – 12, 15 – 17