Unit Title SBL 204 PROTEINS & ENZYMES

UNIVERSITY OF NAIROBI SCHOOL OF BIOLOGICAL SCIENCES Unit Title SBL 204 – PROTEINS & ENZYMES

Purpose The unit aims to give a comprehensive coverage on description, functions and importance of highly specialized structural and diverse macromolecules which catalyze all biochemical reactions that collectively constitute intermediary metabolism of all living organisms.

Course Objectives 1. To provide a concise and comprehensive knowledge of structures and functions of different types of proteins, enzymes, co-enzymes and peptide hormones.

2. To describe and discuss the importance of biocatalysts and their cofactors in sufficient details which are responsible for driving all metabolic reactions.

Expected Learning Outcome By the end of the course unit the learner should be able to:

1. Understand the structural organization and functional diversity of proteins as multipurpose molecules. 2. Describe the pathway and mechanism of protein synthesis and export 3. A comprehensive account of the nomenclature of major classes of enzymes and their functions 4. Discuss the nature, mechanism, specificity, regulation and inhibition of enzyme activity. 5. Evaluate the importance of restriction enzymes in biotechnology 6. Importance of Coenzymes and Co-factors required by certain enzymes for catalysis. 7. Assess the physiological effects of toxic venom proteins, bacterial toxins and pathogenic invasive enzymes. 8. Demonstrate a thorough understanding hormonal role of endocrine system. 9. Describe the chemical nature and hormonal functions of anterior and posterior pituitary peptide hormones as chemical messengers.

Course Content Structural & functional diversity of proteins, Protein synthesis, export and secretion. Lipo-proteins & glyco-proteins, collagen & antibodies. Major classes of enzymes. Nature, mechanism & specificity of enzyme catalysis. Activation energy & enzyme kinetics. Factors affecting enzyme activity. Enzyme models. Enzyme regulators & inhibitors. Iso-enzymes, Restriction enzymes. Co-enzymes and Co- factors. Toxic venom proteins & enzymes. Microbial peptide toxins and invasive enzymes. Peptide Hormones. Regulation of Insulin and Glucagon

Learning & Teaching Methodologies: Lectures, PowerPoint presentation, Class discussions, Practical (laboratory) sessions Instructional Materials and Equipment Laptop PC, LCD projector, Lecture Notes, Charts and illustrations, Laboratory with adequate facilities; Internet

Course Assessment Continuous assements (CAT 1 & CAT 2, Laboratory reports 30 %, Examination 70 % TOTAL = 100 % Recommended Text Books BIOCHEMISTRY, 3rd edition (2004), S.C. Rastogi. PRINCIPALS OF BIOCHEMISTRY, (2004), Nelson D. L. PRINCIPALS OF BIOCHEMISTRY (2008), A. Lehninger, D. L. Nelson & Michael M. Cox, 5th Edition PLANT BIOCHEMISTRY, (1997), edited by P.M. Dey and J.B. Harborne, Academic Press. FUNDAMENTALS OF BIOCHEMISTRY, LIFE AT MOLECULAR LEVEL, (2008, 3rd edition), Donalls J. Voet, Judith Voet, Charlotte Prat., John Wiley & Sons CHEMICAL BIOLOGY: An Introduction to Biochemistry, (1973) Bronk J.R. Macmillan, New York Teaching Schedule Lecture Topics Lab 1. PROTEINS Week 1 1.1 Amino Acids as building blocks of proteins formation of peptide bonds 1.2. Functional Diversity of Proteins 1.3 Simple, conjugated, globular and fibrous proteins 1.4 Structural Organization – primary, secondary, Week 2 Lab1.chemical nature of proteins tertiary & quaternary structures 1.5 Effects of pH, temperature, salts and metal ions on proteins 1.6 Structure and biological functions Lipo-proteins & Glyco-proteins 1.7 Structure and biological functions of Collagen and Antibodies 1.8 Protein Synthesis Week 3 Pathway to making a protein - transcription and translation Illustrative description and role of ribosome, t-RNA and m-RNA Description of 4 major steps of protein synthesis 1.9 Protein Export & Secretion Significance Vesicular transport – endocytosis and exocytosis Process of protein secretion 2. ENZYMES Week 4 Lab 2. Effects of metal ions, 2.1 Enzymes as biological catalysts cations and salt concentrations on 2.2 Nomenclature based on substrates catalysed prtotieins 2.3 Classification of 6 major groups with examples of specific types of catalysed reactions 2.4 Enzyme vocabulary – substrate, product and active site 2.5 Enzyme specificity 2.6 General properties of enzymes Week 5 2.7 Characteristics of the active site 2.8 Enzyme–substrate interaction 2.9 Enzyme models 2.10 Concept of activation energy & overview of Week 6 Lab 3. Isoelectric point of proteins enzyme kinetics and its significance 2.11 Factors affecting of enzyme action, temp, pH, substrate and enzyme concentration 2.12. Enzyme Inhibition – reversible & irreversible, competitive and non-competitive 3 ENZYME REGULATION Week 7 3.1 Feed back inhibition 3.2 Allosteric regulation 3.3 Multi-enzyme systems 3.4 Homotropic and Heterotropic regulation 3.5 Characteristic features and function of iso-enzymes CAT 1 4. Co-ENZYMES & Co-FACTORS Week 8 Lab 4. Hydrolytic enzyme - 4.1 Non-protein organic and inorganic compounds Invertase 4.2 Function as helper molecules of enzymes 4.3 Classification and Role of Co-enzymes 5. RESTRICTION ENZYMES Week 9 5.1 Definition 5.2 Mode of Action 5.3 Significance and applications in genetic engineering & biotechnology 6. VENOM TOXIC PROTIENS AND ENZYMES Week Lab 5. Effect of pH on catalytic 6.1 Main effects of venom toxins 10 activity of Catalase 6.2 Physiological effects of cardiotoxin, myotoxin and neurotoxin 6.3 Role of Hyarulonidase as a toxic enzyme 7. MICROBIAL TOXINS AND INVASIVE ENZYME Week 7.1 Pathogenic effects of microbial proteins 11 (polypeptides) 7.2 Exotoxins and Enterotoxins, examples and physiological effects 7.3 Endotoxins, examples and physiological effects 7.4 Definition of invasive enzymes 7.5 Examples and mode of action of invasive enzymes 8. PEPTIDE HORMONES Week 8.1 chemical nature of protein based hormone 12 8.2 Hormones as chemical messengers 8.3 Mode of action 8.4 Role of Hypothalamus and Pituitary glands 8.5 Structure and physiological effects of posterior pituitary gland hormones 8.6 Structure and physiological effects of anterior pituitary gland hormones 8.7 Metabolic regulation of blood sugar by insulin & glucagon CAT 2 Examinations Weeks 14/15