Tertiary Protein Structure

Tertiary Protein structare 1 poly Peptide subunit monomer. Contain all type of bonds. 3 dimensional structure and biological function... stabilized by weak bond between side chains Exterior pelar a a Disulfide bond S-S CH Thydro pliage hond onteretien Tante bond ega myoglobin "O2 storage Compact subunit Protomere or monomere Contain many a helix or Bsheet or both to provide hydrogen bond for stability prevent water to enter protein Core Domain special part of tertiary protein has specific function. Active site Catalysis, Domin irudie S Enzyme Tertiary globular protein Types of bonds in tertiary protein. A Covalent bond peptide bond Amid bond Disulfide bond B Non Covalent weak bond Hydrogen bond Hydro phobic interaction Ionic bond Electrostatic bond or salt bridge - Van der waal Porces. All bands are found in tertiary protein. * Quaternary - 2 4 oligomer or multimerne 2 or more poly peptide subunits linked by weak bond The subunits Can be identical or different Round in laver praicrens Hexokinase Ey & Dimer 2 subunit nimol, Ionis bond enzyme Hydrogen bond, hydrophobic bond nistong vandole goitist Tetramer 02 2 4 subunit 2x,2 β Hemoglobin A Protein denaturation &.. Destruction of all bonds except peptide bond loss of quaternary tertiary secondary structure but not primary structure most of denaturation is irreversible egg albumin aphysical heat Temp shaking X-ry U.v Coagulation pressure N Fold protein (native) strong acid HCL Strong base MOH Heavy metals • Lond mercury detergeat salts» primary structure 2 Chemical ageats Loss of 3D structure • Tviscosity, ↑ digestability • Loss of biological function • Loss of antigenicity - Example of dinaturations Denaturation urea Ribonuclease +BME N primary enzyme renaturation A Tertiary «folded 1) *Fibrous proteins scle ro proteins water insoluble, not digested by pepsin, trypsin Axial henght = ↑lo Long fibers widt •Contain small hydrophobic aras glycine, alanine, val II-keratin skin, hair, nails motif Right handed 3 helix Linked by disulfide bonds Contain hydrophobica.as: Ala, phe, Val, glycine motif 2 helix helix -B-keralin Contain antiparallel B-sheet Pound in fibroinusilk. Round in animal claws horns and hooves 121 Elastin- • Rubber like 4 poly peptide chains • Contain: glycine alanine & Valive. small aras. Rich in proline, lysine. Q Le poor in Hydroxyproline Hydroxylysine.. just in colagan • Elastin boiling does not give gelatin. •Elastin contain: Desmosine • Elastin: Pound in lungs / Liver / and blood vessels. • Neutrophils produce elastase enzyme that attack elastin in lungs, Liver. •1- antitrypsin (AT protect elastin in lungs and liver from elastase enzyme -21-antitrypsin deficiency Genetic / smoking Liver Cirrhosis 12 Emphysema Alveolar destruction" 131 Collagen 30% of protein • produced by fibroblast to extracellular matrix 12 types, but type I consist 90% Type I is found in bons/teeth / tendon/Cornea / and blood vessels. Collagen boiling denaturation →gelatin derived proteen Digested by pepsin, trypsin «Indigestable Crossing point -Collagen Contain glycine each 3rd position to stabilize the triple helix by hydrogen bond. Collagen Contain repeated turns Glycine-x-y 33% 10%, 10% x = proline and ad y-Hydroxglysine. Hydroxy proline it's repeated 333 times. Glycine Pro selle Tropo collagen structure) basic unit schise leg • 3 helical poly peptide are left handed but Coil on each other in right handed superhelex formed ofter Collagen synthsis Q. proline prolyl oxidase hydroxyproline vit. Cco Pactor Lysine. lysyl oxidase hydroxylysime provide H. bond •Hydroxy lysine Can be glycosylated Lysin oll-sugar •Diseases of Collagen Collagenopathies TI Scurvy Vit.C -Gum bleeding. bone fructure. - Loose teeth. - delay wound healing. 121 menke disease -Gray kinky hair infant. _Growth retardation. -Copper malabsorption. - + Collagen Cross linkage due to defect of Lysyl oxidase. 131 osteogenesis imperfecta "101" Absence of glycine at Crossing. Blue sclera, easy bone fructure. 141 Ehler Danlose syndrome -Defect of x. Chain in Collagen. _easy stretched skin, joint sublaxation. Globular Proteins Compact Axial Lenght width - myoglobin O2 reservoir in muscle and heart Rich in histidine, lysine Poor in Cysteine - 80% is formed by a-helix, make & structure (A-H) Polara a on surface, hydrophobic a.a in interior -Contain "heme as 11 prosthetic group limon pictean -myoglobin in single poly peptide Tertiary protein, proximal histidine bind to heme by Sth Coordinate bond give heme stability" +2 Distal histidine stabilize O2 and prevent Fe oxidation