Enzymes 2 nd Year Nutrition By Eman Mokbel Alissa, Ph.D.

Lecture (1): Lecture Content Enzyme definition Nomenclature Classification Coenzymes Properties 2 hypothesis of enzyme specificity

Lecture (2): Lecture Content Mechanism of enzyme action Mechanism of enzyme catalysis The Enzyme Substrate Complex Factors Affecting Reaction Velocity Enzymes Kinetics Michaelis-Menten equation Linweaver-plot

Lecture (3): Lecture Content Enzymes Inhibitors: –Reversible and irreversible –Competitive and noncompetitive Medical relevance of enzyme Inhibitors Antibiotics Enzymes Clinical Application

Lecture (4): Lecture Content Allosteric enzymes Allosterism vs. Cooperativity Allosteric Enzymes Kinetics Feed back inhibition Homotropic and Heterotropic effectors Enzyme Activity Regulation Enzyme measurements Plasma Enzymes Serum enzymes in Diagnosis Isozymes

Amino Acids Metabolism Amino Acids Metabolism 2 nd Year Nutrition By Eman Mokbel Alissa, Ph.D.

Lecture (1) content amino acids in anabolic pathways amino acids degradation Carbon skeleton of amino acids amino acids Pool Inter-tissue Relationships in amino acids Metabolism Protein Turnover Nitrogen balance Digestion, Absorption and Transport

Lecture (2) content Relationship to central metabolism Nitrogen disposal 1.amino acids oxidases 2.Transamination (aminotransferases/ transaminases) 3.Glutamate dehydrogenase ( amino acids oxidative deamination) Ammonia transport to liver 1.Glutamine cycle 2.Glucose- Alanine cycle Urea Cycle –Regulation of urea cycle –Link between urea cycle and TCA cycle

Lecture (3) content Sources and Fates of Ammonia Hyperammonemia Essential and nonessential amino acids Glucogenic and ketogenic amino acids Synthesis and degradation in fasting and fed states Nonessential amino acids synthesis

Lecture (4) content Catabolism of carbon skeleton of amino acids Tetrahydrobiopterin (BH 4 ) Role of folic acid in a a metabolism S-adenosyl methionine (SAM) Metabolism of branched chain amino acids Clinical relevance

Lecture (5) content Metabolic defects in a a metabolism 1.Phenylketonuria 2.Maple syrup urine disease 3.Albinism 4.Homocystinuria 5.Alkaptonuria A A conversion to specialized products 1. Porphyrins 2. Catecholamines 3. γ-aminobutyrate 4. Glutathione 5. Creatine 6. Histamine 7. Serotonin 8. Melanin

Hormonal Control Hormonal Control 2 nd Year Nutrition By Eman Mokbel Alissa, Ph.D.

Lecture (1) content Endocrine system Cell to cell signaling Feedback loops Endocrine axis Factors controlling hormone secretion Assessment of endocrine control Hormones Structure Chemical nature Signal transduction –Hydrophobic hormones –Hydrophilic hormones

Lecture (2) content Overview Insulin –Structure –Synthesis –Metabolic effects –Mechanism of action –Time course of insulin actions

Lecture (3) content Glucagon –Metabolic effects –Mechanism of action Epinephrine –Metabolic effects –Mechanism of action

Metabolic Integration 2 nd Year Nutrition By Eman Mokbel Alissa, Ph.D.

Lecture (1) content Major metabolic pathways Hormonal control Fuel metabolism Control of intermediates flow through metabolic pathways Absorptive state Liver –CHO metabolism –Fat metabolism –A A metabolism Adipose tissue –CHO metabolism –Fat metabolism Resting skeletal muscle –CHO metabolism –Fat metabolism –A A metabolism Brain –CHO metabolism –Fat metabolism

Lecture (2) content Fasting state Metabolic fuels Enzymatic changes in fasting state Mechanisms involved in switching hepatic metabolism between the well-fed and starved state Postabsorptive state Specialized tissues Liver –CHO metabolism –Fat metabolism Adipose tissue –CHO metabolism –Fat metabolism Resting skeletal muscle –CHO metabolism –Fat metabolism Brain –CHO metabolism –Fat metabolism