Biothermodynamics Cheat Sheet PDF

Booster Prep Booster Cheat Sheets™– Biothermodynamics © Copyright 2024, Booster Prep Inc....

Booster Prep Booster Cheat Sheets™– Biothermodynamics © Copyright 2024, Booster Prep Inc. All Rights Reserved. Chemical Reactions and Energy: Determined by concentration of reactants and products Can be anabolic or catabolic Can be exergonic or endergonic Potential vs. kinetic energy Anabolic: Small molecules assemble to form a larger molecule Exergonic: Free energy is released (spontaneous with −Δ𝐺) Chemical reactions can be combined to drive otherwise Kinetic: Energy in motion (i.e., jumping) Catabolic: Large molecules are broken into smaller molecules Endergonic: Free energy is absorbed (nonspontaneous with +Δ𝐺) nonspontaneous reactions. For example, ATP hydrolysis is Potential energy: Stored energy (i.e., glycogen) an exergonic reaction that facilitates endergonic reactions. Enzyme Structure and Mechanism Enzyme Function Structure of enzymes Enzymes act as catalysts by lowering the activation energy needed for a reaction Most are proteins, but some enzymes are made of RNA (ribozymes) Active Site: The area of the enzyme where the substrate binds Lowering the activation energy increases the Allosteric site: A secondary location where an effector binds (effectors can be rate of reaction (makes it go faster) activators or inhibitors) Characteristics of enzyme function: Mechanism of reactions Substrate specific Enzymes are unchanged by the reaction 1. 1 Substrates (aka reactants) enter the active site of the enzyme Catalyze forward and reverse reactions 2. 2 Enzyme and substrate change shape slightly to better catalyze the reaction Have varying function depending on pH and (induced fit model) temperature PRO-TIP: When the substrate binds the enzyme, it forms the enzyme- Have an active site that binds substrates via substrate complex induced fit 3. 3 The enzyme facilitates the reaction by lowering the activation energy 4. 4 The products are released and the cycle repeats Enzyme Regulation ATP Michaelis Menten Terminology Competitive inhibition Noncompetitive inhibition A source of chemical Vmax: The maximum velocity of the reaction at peak substrate energy. Formed via saturation A substance that mimics the substrate inhibits A substance inhibits the enzyme by binding to a phosphorylation, which enzyme by binding to active site, thus preventing secondary location called the allosteric site creates energy rich Michalis Constant (Km): The substrate concentration at which the binding of substrate triphosphate bond (ATP rate of the reaction is half of the maximum velocity Substrate can still bind, but the inhibitor prevents formation is Inversely represents binding affinity Can be overcome by increasing substrate concentration reaction endergonic) Small Km= less substrate needed to reach Vmax (i.e., higher binding Km stays the same affinity) Km increases Vmax decreases Broken apart via Vmax stays the same hydrolysis, which releases energy and phosphate (ATP hydrolysis is exergonic) ATP stores energy generated from the exergonic reactions in the electron transport chain, and can then be used to fuel endergonic reactions