F BICH 410 1st Edition Lecture 15 Outline of Last Lecture Mutant Hemoglobin Carbohydrates Outline of Current Lecture Monosaccharides Disaccharides and polysaccharides o Sugars are conformationally variable pyransoe can assume either chair or boat conformation but the most stable predominant is when all bulky substituents occupy equatorial positions The only sugar that can simultaneousl have all bulky non H substituents in equatorial position is Beta 2 glucose C2 epimer of glucose mannose C4 epimer of glucose galactose Sugars can be derivitized o Oxidation principle modification reducing sugars causes something else to be reduced and the sugar to be oxidized Aldehyde aldonic acid or onate ie gluconate PRIMARY ALCOHOL Uronic acid or urinate Oxidation of both aldaric acid or arate ie glucarate o Reduction make sugar alcohols o Esterification hydroxyl groups of alcohols can react with acids to produce esters phosphorylated form Have to be able to draw sugar phosphates remove OH and add OPO32o Amino DERIVATIVES replace OH with amino group OH down alpha OH up beta Alpha D glucosamine OH replaced by NH2 Sialic acids derivative of mannose receptor for proteins specifically a receptor for the influenza virus Sugars are energy source and information source Glycosidic bond o Glycoside carb in which the OH of the anomeric C is replace by OR o Those derived from furanose are furanosides derived pyranoses are pyranosides o Hemiacetal and alcohol condense to form acetal and hemiacetal o Can be N or O glycosidic bond o If given alpha D glucopyranosyl 1 4 D glycopyranose must be able to draw Disaccharides o Must be able to draw sucrose lactose cellobiose lactose maltose These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute o The only Beta bond we can digest is lactose because we have lactase which hydrolyzes beta linkages but only from gal to glu We cant hydrolyze cellulose Polysaccharide o Homopolysaccharide storage polysaccharide starch and glycogen both are polymers of alpha D glucose Glycogen is storage polysaccharide of animals Starch is principal food reserve for plants 2 types alpha amylose and amylopectin Alpha 1 4 forms a spiral like structure Amylopectin branch every 24 30 residues Glycogen branch every 8 12 residues o Structural polysaccharides cellulose and chitin both are polymers of Beta D Glucose Cellulose primary component of plant cell wall linear polymer not branched bacteria break down beta cellulose in horses that cant be broken down in humans Chitin principal structural component of exoskeleton of invertebrates Chitin is homopolymer of B 1 4 linked N acetyl D glucosamine residues Three types alpha arranged parallel beta arranged antiparallel gammaarranged 2 parallel and 1 antiparallel o Heteropolysaccarides GAG glucosaminoglycans form a gel like matrix that occupies the extracellular spaces Glucosaminoglycans are unbranched polysaccharides consisting of alternating uronic acid and hexosamine residues Assume extended conformational solution Glucosaminoglycans have protection function GAGs provide viscosity adhesiveness tensile strength o Heparin anti coagulent o Chondroitin sulfate cartilage and tendons most prevalent GAGS o Hyaluronate synovial fluid body joints only GAG not sulfonate o Dermatin sulfate found in skin blood vesselks tendons lungsbring fluid to tissue o Keratin structure tissue hydration carrier Heteropolysaccharides glycoconjugates rarely found by self Varied in composition length and function Polysaccharides can function as information carriers In most cases covalently attached to either proteins or lipids glyconjugated Peptidoglycans major part is oligosaccharide Proteoglycans major part is oligosaccharide Glycoproteins major part is protein Glycolipids major part is lipid o Membrane lipids where hydrophilic head groups are oligosaccharides
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