1. Lesson today Protein Teacher : Isroli Laboratory : Animal Physiology and Biochemistry Faculty : Animal Agriculture Diponegoro University

2. Biological Functions of Proteins Principal organic chemical constituents of body organs and soft tissues Enormous functional diversity –Cell membrane structure and function –Enzymes –Hormones and other chemical messengers –Immune factors (antibodies) –Fluid balance –Acid-base balance –Transport –Source of energy and glucose

3. The Structure of Amino Acids NH2 amino group, COOH carboxyl group, R – side chain group can be a series of functional groups

4. Amino Acids The monomer unit of proteins R is the side chain. One of 20 different chemical compounds Some R-groups are acid (other alkali) Some R-groups are water soluble (others are not) Chiral carbon (L-series)

5. Classification of Amino Acids Classification –Structure –Net charge –Polarity –Essentiality Neutral –Aliphatic –Aromatic –Sulfur Acidic Basic Heterocyclic

6. Aliphatic (opened)

7. Aromatic

8. Sulfur

9. Acidic

10. Basic

11. Heterocyclic

12. Essentiality Essential –Amino acids not synthesize in sufficient amounts in the animal body –Required in the diet Nonessential –Adequately synthesized in the tissue No specific requirement Vary by species

13. Essential Amino Acids Arginine Histidine Isoleucine Leucine Lysine Methionine Phenylalanine Threonine Tryptophan Valine Proline Taurine

14. Abbreviations and Codes Alanine A, Ala Arginine R, Arg Asparagine N, Asn Aspartic acid D, Asp Cysteine C, Cys Glutamine Q, Gln Glutamic Acid E, Glu Glycine G, Gly Histidine H, His Isoleucine I, Ile Leucine L, Leu Lysine K, Lys Methionine M, Met Phenylalanine F, Phe Proline P, Pro Serine S, Ser Threonine T, Thr Tryptophan W, Trp Tyrosine Y, Tyr Valine V, Val

15. Leu L -C-C-CONH 2 -C-CONH 2 -C-COOH-C-C-COOH -H -CH 3 -C-OH-C-SH -C-C-S-C PPro -C-C C N N + -C-C-C-C-NH 3 + -C- -C- -OH -C- N South line Circular line Central line Nan-Kan line Chung-San line Northwest line Aliphatic Amide Acidic Imino, Circular Basic SulfurHydroxy Aromatic -C-C-C-N-C-N N + = C -C-C-C C -C-C-C C C -C C C C HN C-COOH  -C-C OH Gln Q Asn N Asp D Glu E Phe F Arg R Lys K His H Gly G A A Ala V Val I Ile Y Tyr Ser S Thr T Met M Cys C Amino Acid Subway Map Trp W Non-polar Polar Juang RH (2004) BCbasics This is NOT a metabolic pathway

16. POLAR NON- POLAR TyrHis Gly AcidicNeutralBasic Asp Glu Gln Cys Asn Ser Thr Lys Arg Ala Val Ile Leu Met Phe Trp Pro Classification of Amino Acids by Polarity Polar (hydrophilic) or non-polar (hydrophobic), it is the bases of the amino acid properties. Juang RH (2003) Biochemistry

17. The 20 Amino Acids Structure

18. TUGAS Tulis structur 20 asam amino berdasarkan klasifikasi berikut ini 1.A.a. rantai samping alifatik a) glisin b) alanin c) valin 2. A.a. rantai samping hidroksil a) serin b) treonin 3. A.a. rantai samping belerang a) sistein b) metionin

19. 4. A.a. rantai samping karboksil a) aspartic acid b) asparagin c) glutamic acid d) glutamin 5. A.a. rantai samping basa a) arginin b) histidin c) lisin d) hidroksilisin

20. 6. A.a. rantai samping cincin aromatik a) tirosin b) fenil alanin c) tritofan 7. Asam imino a) prolin b) hidroksiprolin

21. Protein

22. Amino Acid (AA)-Protein Peptides (from the Greek πεπτος, "digestible"), are formed through condensation of amino acids through peptide bonds. Amino acids: basic unit Peptides : amino acid chain, containing 2 or more AA. Polypeptides : containing less than 50 AA. Protein : > 50 AA.

23. The Peptide Bond A peptide bond is an amide bond between the carboxyl group of one amino acid and the amino group of the next amino acid O CH 3 O + || + | || H 3 N—CH 2 —C—O – + H 3 N—CH—C—O – O H CH 3 O + || | | || H 3 N—CH 2 —C—N—CH—C—O – + H 2 O peptide bond

24. Peptide Bonds Water Amino acids

25. Peptide bond formation:

26. Disulfide Bonds Two cysteine molecules under oxidizing conditions Intermolecular or intramolecular cross- link

27. Protein Structures ProGlyLeuSer Proteins consist of a long chain of amino acids, the primary structure N OH R H N O H R H N OH R H N O H R H N O H R H N O H R H N O H R H N O H R H Side chain H-bond Backbone Amino acid