Concept explainers
The glycine cleavage system is a group of four enzymes that together catalyze the following reaction:
Use the following information to determine the sequence of reactions carried out by the glycine cleavage system:
a. The first enzyme is a PLP-requiring decarboxylase.
b. The second enzyme is aminomethyltransferase. This enzyme has a lipoate coenzyme.
c. The third enzyme synthesizes N5,N10-methylene-THF and also forms +NH4.
d. The fourth enzyme is an FAD-requiring enzyme.
e. The cleavage system also requires NAD+.
Learn your wayIncludes step-by-step video
Chapter 24 Solutions
Organic Chemistry
Additional Science Textbook Solutions
Essential Organic Chemistry (3rd Edition)
Chemistry: A Molecular Approach
Chemistry: The Central Science (14th Edition)
Chemistry & Chemical Reactivity
Chemistry: A Molecular Approach (4th Edition)
- In the multienzyme sequence shown below, molecules of D are able to fit to the enzyme E1 and prevent the conversion of A to B. What is this action of E called? AE1BE2CE3D a. effector inhibition b. allosteric inhibition c. feedback inhibition d. competitive inhibition by nonproductarrow_forwardMatch the following enzymes and substrates: Enzyme Substrate a. sucrase b. amylase c. lactase d. maltase e. arginase maltose amylose sucrose arginine lactosearrow_forwardCarbonic anhydrase is an enzyme that catalyzes the conversion of carbon dioxide to bicarbonate ion (Section 2.2). It is a metalloenzyme, with Zn2 +coordinated at the active site by three histidine side chains. Propose a mechanism for the reaction.arrow_forward
- Quesrion: Enzyme X exhibits maximum activity at pH = 10.5. X shows a fairly sharp decrease in its activity when the pH goes much lower than 9.5. One likely interpretation of this pH activity is that: a. A His residue on the enzyme is involved in the reaction b. a Glu residue on the enzyme is involved in the reaction c. a Tyr residue on the enzyme is involved in the reaction d. the enzyme uses NADH has a cofactor e. the enzyme uses coenzyme A has a cofactor Please explain why, thanks!arrow_forward3) The enzyme aldolase catalyzes the conversion of fructose-1,6-diphosphate (FDP)to dihydroxyacetone phosphate (DHAP) and glyceraldehide-3-phosphate (G3P). Thereaction isFDP ⇄ DHAP + G3P , ∆rG0(298.15 K) = 23.8 kJ mol−1In red blood cells the concentration of these species are [FDP] = 35 µM, [DHAP] =130 µM, and [G3P] = 15 µM. (Remember that 1.0 µM = 1.0 × 10−6 mol L−1. Thestandard state for reactions in solution can be taken as c0 = 1.0 mol L−1).Calculate ∆rG in a red blood cell at 25 0C. Will the reaction occur spontaneouslyin the cell at this temperature?arrow_forward1. Why would a glucose test strip be used to determine the enzymatic activity of Lactase? a). Do lactase enzymes show specificity?arrow_forward
- ANSWER ALL QUESTIONS 4(a) Suggest a test you will use to show that a given food substance contains protein. Show how you will use Modified Gabriel’s Synthsis Streckers’s Synthesis to prepare phenylalanine in the laboratory. 5 (a) Describe in detail how you will determine the primary structure of protein. You have been given a mixture of lysine, histidine and cysteine. The isoelectric point of the amino acids are as follows: Histidine 7.64 Lysine 9.74 Cystenie 5.02 Show how you will separate the mixture into the pure forms. State and describe any instrument that you will use to separate the components in the mixture.arrow_forward4. The amino acid Asp189 lies at the base of the substrate specificity pocket in the enzyme trypsin. a. How is this related to typsin’s substrate specificity? Briefly describe the interactions between the substrate and the Asp 189. b. If the Asp189 was replaced with a lysine residue, how would this affect substrate specificity? c. The scientists that actually mutated the Asp189 to a lysine analyzed the three-dimensional structure of the enzyme and found that the lysine is actually not located in the specificity pocket. Instead, the Lys side chain reaches out of the base of the pocket, rendering the pocket nonpolar. With this additional information, determine how the substrate specificity would differ in the lysine-mutated enzyme.arrow_forwardAn enzyme whose KM is 10-4 M in the presence of a substrate concentration of 10-2 M It is capable of transforming 20% of the substrate in 10 minutes. Calculate how much substrate is had transformed in 20 minutes.arrow_forward
- The anti-obesity drug orlistat works by irreversibly inhibiting pancreatic lipase, an enzyme responsible for the hydrolysis of triacylglycerols in the intestines, so they are excreted without metabolism. Inhibition occurs by reaction of orlistat with a serine residue of the enzyme, forming a covalently bound, inactive enzyme product. Draw the structure of the product formed during inhibition.arrow_forwardSubject :- Chemistr The alpha-beta and beta-gamma phosphate groups are destabilized how? A. resonance B. hydrophobic interactions C. magnets D. through electrostatic repulsionarrow_forwardTPP is a coenzyme for transketolase, the enzyme that catalyzes the conversion of a ketopentose (xylulose5-phosphate) and an aldopentose (ribose-5-phosphate) to an aldotriose (glyceraldehyde-3-phosphate) and a ketoheptose (sedoheptulose-7-phosphate). Notice that the total number of carbons in the reactants and products is the same (5 + 5 = 3 + 7). Propose a mechanism for this reaction.arrow_forward
- Chemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry for Today: General, Organic, and Bioche...ChemistryISBN:9781305960060Author:Spencer L. Seager, Michael R. Slabaugh, Maren S. HansenPublisher:Cengage Learning