67117 - General and Nutritional Biochemistry

Learning outcomes

At the end of the course, the student has the basic knowledge of the structure and functions of the major biomolecules. He also knows the major metabolic pathways and their regulation and the transmission of genetic information from DNA to proteins. The student has also aquired competence on the role of macro-and micronutrients, nutraceuticals and dietary products.

Course contents

Properties of biomolecules : General structures of biomolecules, refer to thermodynamic notions, water properties, weak bonds in biomolecules.

Amino acids and proteins: Structure and properties of amino acids. Peptide bonds and primary structure. Secondary structure. Fibrous proteins. Tertiary structure: protein folding and misfolding. Quaternary structure.

Oxygen binding proteins: Structures and functions of myoglobin and hemoglobin, the heme group. Oxygen binding and cooperativity. R and T states. Allosteric regulation by pH (Bohr effect), CO2, 2,3-DPG. Hemoglobin variants.

Carbohydrates: Monosaccharides, disaccharides, polysaccharides.

Nucleosides and nucleotides: Nucleobases: purines and pyrimidines. ATP structure. Roles of nucleotides. Cyclic nucleotides.

Lipids and membranes: Fatty acids, triacylglycerols, glycerophospholipids, sphingolipids, steroids. Bilayers. The fluid mosaic model. Membrane proteins. Lipid rafts and membrane fluidity. Plasma lipoproteins.

Properties and actions of enzymes: Activation energy. Reaction rate and equilibrium. Active site and ES complex. Catalytic mechanisms. Specificity, pH and T effects. Enzyme classification. Michaelis-Menten kinetics. Enzymatic inhibition. Regulation of enzyme activity: allosteric enzymes, R and T states, positive and negative effectors; covalent modification.

Signal transduction: Signalling molecules, receptors, specificity, amplification and cellular response. G protein coupled receptors. Tyrosine kinase receptors. Mechanism of action of lipophilic and hydrophilic hormones.

Overview of metabolism: The meaning of catabolism and anabolism. ATP and “high-energy” compounds. Coupled reactions. Redox reactions. Coenzymes: structures and functions.

Glucose catabolism: The reactions of glycolysis. The anaerobic fate of pyruvate: fermentations. Regulation of glycolysis. The aerobic fate of pyruvate. Mitochondrion structure. Pyruvate dehydrogenase reaction and its coenzymes.

Tricarboxylic acid cycle: Reactions and regulation. Tricarboxylic acid cycle as a source of biosynthetic intermediates. Anaplerotic reactions.

Electron transport chain and oxidative phosphorylation: Flavoproteins, iron-sulfur proteins, Coenzyme Q, cytochromes. Description of the four respiratory complexes. Protonmotive force. ATP synthase. Uncoupling and inhibition of electron transport chain. Substrate transport systems (shuttles).

Glycogen metabolism and gluconeogenesis: Liver glycogen breakdown, synthesis and control. Gluconeogenesis: reactions and regulation. Hormonal regulation of glycemia. Glycogen metabolism in muscles.

Degradation of lipids: Triacylglycerols mobilization. Fatty acid transport in blood. Fatty acid activation. Beta-oxidation of saturated and unsaturated fatty acids. Formation and utilization of ketone bodies.

Fatty acid biosynthesis: Formation of malonil-CoA. Palmitic acid synthesis: reactions and regulation. Elongation and desaturation.

Cholesterol: Roles and notions about biosynthesis of cholesterol.

Catabolism of amino acids: Aminotransferase reactions. Glutamate dehydrogenase. Transport of nitrogen to liver. Synthesis of carbamoyl phosphate. The urea cycle. Metabolites derived from amino acids degradation.

Chemical structures of nucleic acids: The phosphodiester bond; enzymatic and non enzymatic hydrolysis of DNA and RNA. DNA double helix, complementary base pairing, denaturation. RNA: modified bases, hairpins and loops. Structures and function of different types of RNA.

DNA replication in prokaryotes: The central dogma. Steps in DNA replication. Characteristics of DNA Polimerase III and I in E. Coli. Fidelity of replication and proof-reading. DNA damage and mutations.

RNA transcription in prokaryotes: Characteristics of RNA polymerase in E. Coli. Steps in DNA transcription. Fidelity of transcription. Promoters. Constitutive and non constitutive genes. Ribosome structure. Aminoacyl-tRNA synthethases and amino acid activation.

The genetic code: Definition, reading frames, codons, degeneration, mutations. Codon-anticodon interactions. The"wobble" pairing.

Protein synthesis: The Shine-Dalgarno sequence. Initiation. Chain elongation. Formation of a peptide bond. Chain termination.

Steps in DNA cloning

SECOND MODULE - NUTRITIONAL BIOCHEMISTRY

NUTRITIONAL STANDARDS, GUIDELINES and CALORIMETRY Definition of Food Science and Nutrition Science. Categories of nutrients, macronutrients and micronutrients. From nutrients to foods. The seven classes of foods. Nutritional quality of food. Nutrition and Health. Food and energy. Body mass index (BMI), biochemical evaluations and its use to diagnose the defect and overweight in adults, RDA. Formulation of dietary guidelines. Food pyramids.

WATER Water balance. Water requirements. Endogenous and exogenous sources. Water homeostasis in the body. Water hardness. Water as a drink.

AVAILABLE AND NOT AVAILABLE CARBOHYDRATES Monosaccharides, disaccharides, polysaccharides. Nutrition and metabolism of carbohydrates. Lactose intolerance. Galactosemia. Glucose metabolism. Need of carbohydrates. Foods and glucose tolerance, glycemic index, nutrition and diabetes. Dietary fiber: Resistant starch. Soluble and insoluble fibers. Solubility, viscosity and fermentability of dietary fiber. Benefits and negative effects of the fibers. Recommended intake levels. Food sources. Dietary fiber and health.

PROTEINS Nitrogen balance. Protein turnover. Nutritional features of aminoacids. Transamination reactions. Protein needs and requirements of essential aminoacids. Nutritional value of proteins. Food sources of proteins and protein quality. Protein-energy malnutrition. Celiac disease.

LIPIDS Classification, metabolism, function and food sources of lipids. Monounsaturated and polyunsaturated fatty acids. Trans fatty acids. Plasma lipoproteins. Intake recommendations. Cholesterol. Relationship between lipids and diseases. Essential fatty acids (Linoleic acid and alpha-linolenic acid): metabolic functions, RDA, food sources of Omega-6 and omega-3. Cholesterol function, nutrition and control of serum cholesterol concentration. Lipoproteins.

ALCOHOLIC BEVERAGES Ethanol metabolism, diet and alcoholism.

COFFEE, TEA and CHOCOLATE Properties and effects on various organ system of the xanthines, particularly caffeine

VITAMINS Differences between water-soluble and fat soluble. Nomenclature, sources and properties. Possible causes of deficiencies. B vitamins: general. Vitamins B1, B2, B3, B5, B6, B8, B9, B12, C: food sources, functions, deficiency. Fat-soluble vitamins A, E, K, D: vitamin molecules to activities, functions, food sources, requirements, deficiency and toxicity.

MINERAL Biochemical functions. Bioavailability. Causes of loss of minerals. Functions, deficiencies and toxicity of sodium, potassium, calcium, phosphorus, magnesium, fluoride, iodine, manganese, copper, zinc, selenium and iron.

REACTIVE OXYGEN SPECIES AND ANTIOXIDANTS Reactive oxygen and nitrogen species and oxidative stress. Intracellular and extracellular antioxidants.

FUNCTIONAL FOODS AND NUTRACEUTICALS Functional foods and nutraceutical compounds in the prevention of chronic degenerative diseases.

DIETARY SUPPLEMENTS definition and legal regulation in the EU. Reasons for taking supplements. Vitamin and mineral supplements: judging the adequacy of micronutrient intakes. Protein supplements. Branched chain aminoacids and creatine: rationale and evidence for the use of supplements

Readings/Bibliography

- D.L. Nelson, M.M. Cox "Lehninger. Principles of Biochemistry", VIIth edition, W.H. Freeman and Co, 2017

- J.M. Berg, J.L. Tymoczko, , G.J. Gatto Jr., L. Stryer “Biochemistry”, IXth edition, W.H. Freeman and Co, 2019

- G. Arienti "Le basi molecolari della nutrizione", Vth edition, Piccin, 2021

- U. Leuzzi, E. Bellocco, D. Barreca "Biochimica della nutrizione", Zanichelli, 2013

- C. Pignatti "Biochimica della nutrizione", Società Editrice Esculapio, 2022

Teaching methods

The course comprises 2 modules, General Biochemistry (6 credits) and Nutritional Biochemistry (3 credits). During the frontal teaching lessons, slides will be projected to fully illustrate all the topics of the Course.

Assessment methods

The assessment provides a single final exam, consisting in an oral test on both modules.
The first part of the exam aims at testing the knowledge acquired by the student in General Biochemistry: structure and function of the major biomolecules, metabolism and its regulation, transmission of genetic information.
Only after a positive evaluation, the exam will continue with the assessment of the knowledge of Nutritional Biochemistry , with particular regard to the role of macro- and micro-nutrients, dietary products and nutraceuticals.
In the final evaluation, the commission ensures that the student has achieved the course objectives and also his ability to have an overview of the subject and to use a proper and specific language. 

Teaching tools

The Virtuale platform, provided by University of Bologna, allows the access to the slides deposited by the teachers.

The Platform allows also the communication between students and teachers.

Office hours

See the website of Diana Fiorentini

See the website of Cecilia Prata