compare and contrast the lock and key model versus the induced fit model of enzy

ID: 556695 • Letter: C

Question

compare and contrast the lock and key model versus the induced fit model of enzyme activity. which will best suit the results in an enzymatic reduction of a ketone?

EXPERIMENTS MATIC RESOLUTION IN THIS EXPERIMENT, ethyl acetoacetate is added to a fermenting sugar solution. After two days, the product formed by the chiral reduction of the methyl ketone of the starting material is extracted with ether. The ether is dried and evaporated to give an optically active hydroxyester. Microscale Procedure In a 25-mL flask, dissolve 2.3 g of sucrose and 15 mg of disodium hydrogen phos- phate in 8.5 mL of warm (35°C) tap water (see Experiment 1). Add 0.5 g of dry yeast and swirl to suspend the yeast throughout the solution. After 15 minutes, while fermentation is progressing vigorously, add 150 mg of ethyl acetoacetate. Store the flask in a warm place, ideally at 30-35°C, for at least 48 hours (a longer time will do no harm). At the end of this time, add 0.5 g of Celite filtration aid and remove the yeast cells by filtration on a Hirsch funnel (see Experiment 1). Wash the cells with 1.5 mL of water; then saturate the filtrate with sodium chloride to decrease arm; the reaction eratures. In: Application of Biochemical Systems in Organic Chemistry, Part 1. Jones JB, Sih CJ, Perlman D. Wiley: New York, 1976;71-78 on Lett. 1982:23:159-162 1981;37:1341 M. Chem Commun. 1975;400 A, Moretti I, Torre G. Synthesis. 1983;897. arning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part gage Learning, Inc. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part rganic Experiments d the solubility of the product. Refer to a handbook for the solubility of sodium chlo- sride in water to determine approximately how much to use. Extract the resulting solution five times with 1.5-mL portions of ether in a test tube, taking care to shake hard enough to mix the lavers but not so hard as to form an emulsion between the ether and water. Adding a small amount of methanol may help to break up emul- sions. Dry the ether layer by adding anhydrous sodium sulfate or calcium chloride pellets until the drying agent no longer clumps together. After approximately 15 minutes, filter the ether solution into a tared flask and evaporate the filtrate. The remaining residue should weigh about 100 mg. It should, unlike the starting mate- rial, give a negative iron (III) chloride test. It can be analyzed by thin-layer chro- matography (TLC), using dichloromethane as the solvent, to determine whether unreacted ethyl acetoacetate is present. Infrared (IR) spectroscopy should show the n presence of the hydroxyl group, and may show unreduced methyl ketone. The nuclear magnetic resonance (NMR) spectrum of the product is easily distinguished from that of the starting material Cleaning Up. Dilute the aqueous layer with water and flush it down the drain After the ether evaporates from the drying agent in the hood, place the drying agent

Explanation / Answer

Lock and Key Model

Induced Fit model

Active Side is made of single components

Active side is made of two components

Active side is Static

Active side is not static

No transition state

Transition state is considered

No separate catalytic group

Separate catalytic group is observed

Induced Fit model will be best suitable in an enzymatic reduction of a ketone.