BIOCHEMISTRY - channel 1

BIO/10 - 9 CFU - 2° Semester

Teaching Staff

GIUSEPPE LAZZARINO


Learning Objectives

To acquire the knowledge on structure, function and regulation of biological macromolecules. To understand the general mechanisms of regulation of metabolism. To acquire the knowledge on the main pathways and cycles of metabolism, with particular attentio to metabolism of carbohydrates, lipids and amino acids. To understand the general mechanisms of metabolic alterations under non-physiological conditions (prolonged starvation, physical stress).


Course Structure

Frontal lessons with practise on chemical formulae and metabolic cycles.



Detailed Course Content

Recalls of inorganic and organic chemistry. Carbohydrates – structure and fucntion. Lipids – structre anf funtcion. Purines and pyrimidines – structure and function. Amino acids – structure and function. Peptide bond and its characteristics. Peptides of biological relevance. Proteins – structure and function. Classification. Primary structure. Secondary structures: alfa-helix, beta-strand, collagen helix. Tertiary structure. Quaternari structure. Relationship between primari structure and conformation. Denaturation and rinaturation. Protein folding. Fibrous proteins. Globular proteins. Hemoproteins involved in the transport of gases (O2, CO2). The heme goup. Tridimensional structures of myoglobin and hemoglobin. Mechanism of oxygen bnding to myoglobin and hemoslobin. Oxygen affinity. Saturation curves, Bohr effect, cooperativity, Hill plot, homotropic and heterotropic interactions. The effect of 2,3-DPG. The Monod-Wyman and Chengeux (MWC) model and the sequential model. T and R states. Heterogeneity of circulating hemoglobin. Methemoglobin reductase, reduced glutathione (GSH) and NADPH for the maintenance of hemoglobin functions. Deficit of G-6-PDH, oxidation of haemoglobin, malaria. Molecular pathology of abnormal haemoglobin. Enzymes. Classification. Coenzymes and vitamins. Chemistry and bilogical catalysts. The Michaelis-Menten equation. Km, Vmax, turnover number, Kcat/Km. Reversibile and irreversibile inhibition. General mechanisms of enzyme catalysis (acide-base catalysis, covalent catalysis, state transitino catalysis, metal ions catalysis). Multimeric enzymes and allosteric regulation. Mutlienzymatic complexes. Regulation of enzymatic activity. Examples of regulation of metabolic sequences. Feed-back inhibition. Cascade amplification. Isoenzymes. Introduction to metabolism: its general organization. Understanding pathways and metabolic maps. Catabolism and anabolism. Bioenergetic. Energetically relevant molecules. Use of biochemical energy within the cell.Introduction to metabolism: its general organization. Understanding pathways and metabolic maps. Catabolism and anabolism. Bioenergetic. Energetically relevant molecules. Use of biochemical energy within the cell. The biochemical reactions of glycolysis – Regulation of glycolysis. Oxidation of pyruvate: the pyruvate dehydrogenase. Degradtion of glycogen – The glycogen phosphorylase and its hormonal control. The transduction of the hormonal signal within the cell: G-proteins, cyclic AMP, adenylate cyclase, protein kinase. Reactions of the citric acid cycle – Regulation of the cycle. Reactions of the pentose phosphate shunt and its biochemical importance. Oxidative phosphorylation – The mitochondrion as the energetic plant of the cell. The scale of redox potential of biologically relevant molecules. The machinery for the electron transport: structure and function of the complexes I, II, III and IV. The sulphur-iron centres. The Q-cycle in the complex III. The transmembrane complexes in the electron transport. The electrochemical potential in electron transport. Oxygen utilization. The ATP synthase: structure and mechanism of action. Transport of nucleotides through mitochondria: the adenine nucleotides transporter. The beta-oxidation reactions. Absorption and transport of dietary lipids. Activation of lipolysis and transport of free fatty acids. Activation and transport in mitochondria. The four reactions of the beta-oxidation. Regulation and energy yield. Relationship with glucose metabolism. Ketogenesis. Transamination and transdeamination of amino acids. The urea cycle. Degradation of nucleotides. Catabolism of purines and pyrimidines . Degradation of heme: structure and function of biliary salts. Biosynthetic pathways. Gluconeogenesis. The reaction of carboxyaltion of pyruvate and the reactions of gluconeogenesis. Relationship between glycolysis and gluconeogenesis. Glycogen biosynthesis. Biosynthesis and recovery of purines and pyrimidines. Biosynthesis of heme. Biosynthesis of fatty acids. Biosynthesis of cholesterol. Mechanisms of regulation of metabolism.



Textbook Information

David L. Nelson, Michael M. Cox Lehninger Principles of Biochemistry Editor: W.H.Freeman & Co Ltd

 

BERG JM, TYMOZCKO JJL, STRYER L. Biochemistry Editor McMillan

 

VOET and VOET Biochemistry Editor Wiley




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