1. By DC

2. H2OH2O How much of you is protein?

3. Amino Acids: “Dry” form Carboxylic acid Amino group Radical group

4. Ionization? What’s it do in water? H+H+ H+H+ “wet” form

5. Amino Acids: (cont) 20 various radical groups nonpolarsome nonpolar polar or chargedsome polar or charged

6. Condensation or Dehydration Synthesis

7. Peptide bond Dipeptide dipeptide Synthesis of a dipeptide:

9. Protein Structure: The final shape of a protein determines its function Proteins are either globular or fibrous

10. Levels of Protein Structure: There are four possible levels of folding 1) Primary (1 0 ) 2) Secondary (2 0 ) 3) Tertiary (3 0 ) 4) Quaternary (4 0 )

11. Folding Nothing more than the amino acid sequence What forces hold it in this structure? ex? Lysozyme

12. Pro-Insulin- a globular protein Primary structure

13. Insulin- the finished hormone

14. Folding Actual folding Radicals not involved (yet) Forces responsible? Hydrogen Bonds Two possibilities  Helix &  Pleats

16.  Helix (first type found)

17.  Pleats (the second found)

18. Folding Results in final shape Actual folding Result of radical group interactions Four types of forces

19. Folding Bonding of two different polypeptides Covalently bonded

20. Denaturation of Proteins Destruction of its“native” configuration Environmental cause? 3-D shape is fragile temperature & pH changes

21. Support Keratin

22. Support Collagen

23. Enzymes Catalase Active site 2H 2 O 2 O2O2 2H 2 O

24. Transport Hemoglobin

25. Transport Channel Proteins

26. Transport Microtubules

27. Communication Hormones

28. Communication Receptor Proteins

29. Defense Antibodies

30. Motion Muscle fibers Actin Myosin