Lecture 1.pdf

Department of Biochemistry and Molecular Medicine, UDS – School of Medicine, Tamale BIOLOGICAL CHEMISTRY (SMS 111) Lecture 1: Protein Chemistry Lecturer : Dr. Frederick Sarfo-Antwi  Course Objectives At the end of the lesson, students should be able to describe the stru...

Department of Biochemistry and Molecular Medicine, UDS – School of Medicine, Tamale BIOLOGICAL CHEMISTRY (SMS 111) Lecture 1: Protein Chemistry Lecturer : Dr. Frederick Sarfo-Antwi  Course Objectives At the end of the lesson, students should be able to describe the structure and identify the biomolecules of living cells, such as proteins (amino acids, peptides). Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Biomolecules of Living Cells A biomolecule or biological molecule is a term used to describe molecules present in organisms that are essential to one or more typically biological processes The four major types of biomolecules are carbohydrates, lipids, nucleic acids, and proteins Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus BIO-MEDICAL IMPORTANCE OF PROTEIN Anti-aging Fat-burning Arthritis Healthy skin Osteoporosis Hair loss Cholesterol Menopause Diabetes Performance Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Protein Deficiency (1/3) The term ‘protein deficiency’ represents a state of relative or absolute deficiency of body proteins or one or more of the essential amino acids. Protein turnover’ reflects the balance of protein degradation and synthesis. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  From Amino Acid to Protein Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Digestion of Dietary Proteins The dietary proteins are hydrolysed to amino acids by proteolytic enzymes, which can be easily absorbed. Proteolytic enzymes responsible for degrading proteins are produced by three different organs; ▪ The stomach, pancreas and the small intestine. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Characteristics of Proteolytic enzymes Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Reactions of Proteolytic enzymes Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Role of Biochemistry in Pharmacy Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Biochemistry and Pharmacy Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Mechanisms of Transport Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Characteristics of Proteolytic enzymes Endopeptidase acts inside the core of protein, forms small peptide fragments Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Digestion of Protein starts in stomach When proteins enters the stomach, it stimulates the secretion of the hormone gastrin, from gastric mucosal cells. This gastrin, in turn, stimulates the release of gastric juice, which contains: 1. Hydrochloric acid (HCL) 2. Pepsinogen (zymogen) 3. Rennin (in infants) Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Characteristics of Proteolytic enzymes Endopeptidase acts inside the core of protein, forms small peptide fragments Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Pepsin Act on Endopeptidase acts inside the core of protein, forms small peptide fragments Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus From the Mouth to the Stomach Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus From the Stomach to the Small Intestine Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Mechanisms of Transport Endocytosis – movement of substance or molecule into the cell. Exocytosis – movement of substance or molecule outside the cell. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Characteristics of Proteolytic enzymes Endopeptidase acts inside the core of protein, forms small peptide fragments Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Mechanisms of Transport Endocytosis – movement of substance or molecule into the cell. Exocytosis – movement of substance or molecule outside the cell. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Overview of Protein Digestion Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Protein Breakdown Carries Chemical Energy in cells Serves as Signals Regulatory Molecules Components of Many Enzyme cofactors Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Site for Urea Production Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Summary of Protein Breakdown Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Protein Deficiency (1/4) Protein deficiency, also called hypoproteinaemia, is usually tied to overall low protein intake. The condition affects about 1 billion people worldwide but is rare in the US. Overall, Americans tend to eat the recommended amount of protein needed. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Protein Deficiency (2/4) The term ‘protein deficiency’ represents a state of relative or absolute deficiency of body proteins or one or more of the essential amino acids. Protein turnover’ reflects the balance of protein degradation and synthesis. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Protein Deficiency (3/4) More synthesis than breakdown indicates an anabolic state that builds lean tissues. More breakdown than synthesis indicates a catabolic state that burns lean tissues. NB: The quantitative relationship between circulating amino acid concentrations and their rate of catabolism is not uniform, either between individuals or between diets. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Protein Deficiency (4/4) Although the main cause of protein deficiency is a protein- deficient diet, the disorder can commonly occur in a variety of pathologic states. The dietary treatment of protein deficiency depends on the cause of the deficiency and must depend on a sound understanding of the underlying disorder and the mainstay of treatment includes balanced energy-protein and micronutrient supplementation. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Causes of Protein Deficiency (Hypoproteinemia) Inadequate protein Malabsorption Liver damage Kidney damage Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Mechanisms of Transport Endocytosis – movement of substance or molecule into the cell. Exocytosis – movement of substance or molecule outside the cell. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Signs and symptoms of protein deficiency Edema Fatty Liver Skin, Hair and Nail Problems Loss of Muscle Mass Greater Risk of Bone Fractures Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Effects of Protein Deficiency Edema Fatty Liver Anemia Skin, Hair and Nail Problems Loss of Muscle Mass Greater Risk of Bone Fractures Increased Severity of Infections Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Protein Deficiency in Pregnancy Kwashiorkor Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Causes of Protein Deficiency (Hypoproteinemia) Inadequate protein Malabsorption Liver damage Kidney damage Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Diseases of Protein Deficiency Kwashiorkor Marasmus Cachexia Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Kwashiorkor Kwashiorkor Marasmus Cachexia Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Cachexia Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Disorders Associated with Proteins Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Alzheimer’s Disease Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Amino Acids Amino acids are the monomers that make up proteins. Each amino acid has the same fundamental structure. The precise amino acid content, and the sequence of those amino acids, of a specific protein, is determined by the sequence of the bases in the gene that encodes that protein. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  History of Amino Acids Twenty (20) amino acids exist Asparagine (1806) – asparagus Threonine (1938) Glutamate – wheat gluten Tyrosine – tyros cheese Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Structure of Amino Acid Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Amino Acids share Common Structural Features Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Twenty Amino Acids Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Glycine Amino Acid Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Proline, a cyclic Amino acid Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Proline, a cyclic Amino acid Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Amino Acids can be Classified by R Group Nonpolar, aliphatic R groups Aromatic R groups Polar, uncharged R groups Positively charged R groups Negatively charged R groups Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Nonpolar, aliphatic R groups Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Aromatic R groups Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Polar, uncharged R groups Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Cysteine (sulfhydryl group) Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Positively charged R groups Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Negatively charged R groups Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Negatively charged R groups Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Three letters abbreviation and One letter Symbol Glycine Gly, G Lysine Lys, K Alanine Ala, A Histidine His, H Proline Pro, P Arginine Arg, R Valine Val, V Aspartate Asp, D Leucine Leu, L Glutamate Glu, E Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Three letters abbreviation and One letter Symbol Serine Ser, S Isoleucine Ile, I Threonine Thr, T Methionine Met, M Cysteine Cys, C Phenylalanine Phe, F Asparagine Asn, N Tyrosine Tyr, Y Glutamine Gln, Q Tryptophan Trp, W Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Uncommon Amino Acids Also have Important Functions In addition to the 20 common amino acids, proteins may contain residues created by modification of common residues already incorporated into a polypeptide (Post-synthetic Modification) Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Uncommon Amino Acids Also have Important Functions 4-hydroxyproline (found in collagen) 5-hydroxylysine (found in collagen) 6-N-Methyllysine (constituent of myosin) Gamma carboxyglutamate (prothrombin) Selenocysteine and Pyrrolysine Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Uncommon Amino Acids Structures Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Uncommon Amino Acids Structures Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Transiently Modification of Amino Acids Phosphoryl group (Phosphorylation) Methyl group (Methylation) Acetyl group (Acetylation) Adenylyl group (Adenylylation) ADP-ribosyl (ADP-ribosylation) Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Phosphorylation of Aspartate into Phosphoserine Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Phosphorylation of Aspartate into Phosphoserine Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Disorders Associated with Amino Acids Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Peptides are Chains of Amino Acids Two or more amino acid molecules are joined through a peptide bond. Such a linkage is formed by removal of water (dehydration) from the carboxyl group of one amino acid and the amino group of another amino acid. Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Condensation reaction of Amino Acids Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Hydrolysis reaction of Amino Acids Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus  Sequence of Amino Acids Dipeptide Oligopeptide Tripeptide Polypeptide Tetrapeptide Protein (>10,000) Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Dipeptide Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Tripeptide Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Tripeptide Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Tetrapeptide Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Tetrapeptide Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Oligopeptide Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Polypeptide Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Protein Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Nomenclature of Peptides Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Nomenclature of Peptides Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Amino acids and their Acyl naming Oligopeptide Polypeptide Protein (>10,000) Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus Department of Biochemistry and Molecular Medicine, UDS – SoM, Tamale Campus THE END UNIVERSITY FOR DEVELOPMENT STUDIES