Happy Monday! 9/16/2013 PQ & Journal7.5 & 7.6 Test Wednesday, lets boogy! D 4 Macromolecules in all living organisms: Table 3.1 Polymers are formed in condensation reactions. Figure 3.4 Condensation of Polymers : Water is removed; Cov bond forms b/w monomers Figure 3.4 Hydrolysis of Polymers water is added; cov bond b/w monomers is broken 6 Functions of proteins: (IB) Proteins are made from 20 different amino acids (monomeric units) The composition of a protein: 7.5.2 Outline the difference between fibrous proteins & globular proteins, with reference to two examples of each protein type. FibrousGlobular Shape Solubility Main level of organization Function Examples Parts of an amino acid Amino acids have These hydrophylic amino acids attract ions of opposite charges. Table 3.2 (Part 1): HYDROPHILIC AMINO ACIDS Hydrophylic amino acids with polar but uncharged side chains form hydrogen bonds Table 3.2 (Part 2): POLAR, UNCHARGED (HYDROPHILIC) Table 3.2 (Part 3): NONPOLAR, HYDROPHOBIC Hydrophobic amino acids Table 3.2 (Part 4): WEIRDOS Figure 3.5 Disulfide Bridge FORMATION BETWEEN TWO CYSTEINES (covalent bond) Figure 3.6 Formation of Peptide Bonds: amino of 1, carboxyl of another peptide bond (condens.) The peptide bond is inflexibleno rotation is possible. Primary Structure: Figure 3.7 The Four Levels of Protein Structure Amino acid monomersPeptide bond Secondary structure: helix pleated sheet Figure 3.7 The Four Levels of Protein Structure Secondary Structure: Helix Hydrogen bond Figure 3.7 The Four Levels of Protein Structure Pleated sheet Secondary Structure: Hydrogen bond Tertiary structure: Figure 3.7 The Four Levels of Protein Structure Tertiary Structure Pleated sheet Helix Hydrogen bond Disulfide bridge Quaternary structure results from the interaction of subunits by Figure 3.7 The Four Levels of Protein Structure Quaternary Structure: Figure 3.9 Quaternary Structure of a Protein Figure 3.10 Noncovalent Interactions between Proteins and Other Molecules Ionic bonds b/w charged R groups 2 nonpolar groups interact hydrophobically H bonds form b/w 2 polar groups Figure 3.11 Denaturation Is the Loss of Tertiary Protein Structure and Function Destroys its biological functions Renaturation: sometimes possible, but usually not 6 Energy, Enzymes, and Metabolism Alcohol dehydrogenase: catalyst for breakdown of alcohol Catalysts speed up the rate of a reaction. Activation Energy Enzyme-Catalyzed Reactions Figure 6.9 Enzyme and Substrate Figure 6.10 Enzymes Lower the Energy Barrier Figure 6.12 Some Enzymes Change Shape When Substrate Binds to Them: INDUCED FIT Some enzymes require partners: Prosthetic groups: Cofactors: Coenzymes: Figure 6.14 Catalyzed Reactions Reach a Maximum Rate 7.6.1 State that metabolic pathways consist of enzyme-catalysed reactions in: Chemical rxns usually multiple steps Each step has own enzyme Chains (glycolysis) Cycles (Krebs, Calvin Cycles) Figure 6.17 Reversible Inhibition inhibitor & substrate compete for active site Figure 6.17 Reversible Inhibition inhibitor binds to alternative site (not active site) & changes shape of active site Online Animated Tutorial Figure 6.18 Allosteric Regulation of Enzymes INACTIVE FORMACTIVE FORM Inhibitor site Active site Activator site Catalytic subunit Regulatory subunits The enzyme switches back and forth between the two forms. They are in equilibrium. Online Animated Tutorial Figure 6.18 Allosteric Regulation of Enzymes INACTIVE FORM Allosteric inhibitor Binding of an inhibitor makes it less likely that the active form will occur.