Organic Chemistry (8th Edition)
8th Edition
ISBN: 9780134042282
Author: Paula Yurkanis Bruice
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 23, Problem 29P
What acyl groups have we seen transferred by reactions thiamine pyrophosphate as a coenzymes? (Hint: See problems 9, 10, 11, 27, and 28.)
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Please draw by hand. Triosephosphate isomerase (TIM) catalyzes the conversion of dihydroxyacetone phosphate to glyceraldehyde-3-phosphate. The enzyme's catalytic groups are Glu 165 and His 95. In the first step of the reaction, these catalytic groups function as a base and an acid catalyst, respectively. Propose a mechanism for the reaction.
ОН
2-03Р0
ОН
dihydroxyacetone phosphate
triosephosphate isomerase
2-03РО.
H
glyceraldehyde-3-phosphate
FYI Glu is glutamic acid and his is histadine
4. Liver alcohol dehydrogenase (LADH) catalyzes a reversible, pH-dependent oxidation of an alcohol
to an aldehyde according to the following reaction:
LADH
RCH2OH
+
NAD*
RCHO
+
NADH
+
H*
where NAD* and NADH are, respectively, the oxidized and reduced forms of the cofactor nicotin-amide
adenine dinucleotide. While the reaction is actually a two-substrate reaction, it proceeds like a one-
substrate reaction through a so-called compulsory-ordered ternary complex mechanism. It has been
shown through kinetic studies that, in the case of primary alcohols, the enzyme binds first the cofactor
forming a binary enzyme-NAD* complex that then binds the second substrate, the alcohol, to form a
ternary enzyme-NAD*-substrate complex in which the oxidation of the alcohol proceeds with reduction
of the cofactor.
While the enzyme catalyzes oxidation of various steroids as well as ingested ethanol, it also catalyzes
the oxidation of methanol CH3OH, forming the extremely toxic product formaldehyde HCHO.…
The dynamic process by which both forms of a- and B-D-glucopyranose in solution change slowly into an equilibrium mixture of both is known as
(choose the name).
OH
OH
Но
но
НО
HO
OH
OH
OH
OH
a-D-glucopyranose
36%
B-D-glucopyranose
64%
OA Acetylation
O B. Enediol Rearrangement
OC Mutarotation
O D. Acetal Formation
O E Epimerization
Chapter 23 Solutions
Organic Chemistry (8th Edition)
Ch. 23.1 - Prob. 2PCh. 23.1 - Prob. 3PCh. 23.2 - How many conjugated double bonds are there in a....Ch. 23.2 - Instead of adding to the 4a position and...Ch. 23.2 - Prob. 7PCh. 23.3 - Prob. 8PCh. 23.3 - Acetolactate synthase is another TPP-requiring...Ch. 23.3 - Acetolactate synthase transfers the acyl group of...Ch. 23.3 - Prob. 12PCh. 23.5 - Which compound is more easily decarboxylated?
Ch. 23.5 - Prob. 14PCh. 23.5 - Explain why the ability of PLP to catalyze an...Ch. 23.5 - Explain why the ability of PLP to catalyze an...Ch. 23.5 - The enzyme that catalyzes the C C bond cleavage...Ch. 23.5 - Propose a mechanism for the ,-elimination reaction...Ch. 23.6 - Ethanolamine ammonia lyase, a coenzyme...Ch. 23.6 - Prob. 20PCh. 23.7 - How do the structure of tetrahydrofolate and...Ch. 23.7 - What is the source of the methyl group in...Ch. 23.8 - Thiols such as ethanethiol and propanethiol can be...Ch. 23 - How does the metal ion in carboxypeptidase A...Ch. 23 - Prob. 24PCh. 23 - Prob. 25PCh. 23 - For each of the following reactions, name both the...Ch. 23 - Prob. 27PCh. 23 - When transaminated, the three branched-chain amino...Ch. 23 - What acyl groups have we seen transferred by...Ch. 23 - Propose a mechanism for the following reaction:Ch. 23 - Draw the products of the following reaction, where...Ch. 23 - When UMP is dissolved in T2O, exchange of T for H...Ch. 23 - Dehydratase is a PLP-requiring enzyme that...Ch. 23 - In addition to the reaction mentioned in Section...Ch. 23 - PLP can catalyze both ,-elimination reactions...Ch. 23 - The glycine cleavage system is a group of four...Ch. 23 - Prob. 37PCh. 23 - FADH2 reduces , -unsaturated thioesters to...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- One of the steps in the pentose phosphate pathway for glucose catabolism is the reaction of xylulose 5-phosphate with ribose 5-phosphate in the presence of a transketolase to give glyceraldehyde 3-phosphate and sedoheptulose 7-phosphate. (a) The first part of the reaction is nucleophilic addition of thiamin diphosphate (TPP) ylide to xylulose 5-phosphate, followed by a retro-aldol cleavage to give glyceraldehyde 3-phosphate and a TPPcontaining enamine. Show the structure of the enamine and the mechanism by which it is formed. (b) The second part of the reaction is addition of the enamine to ribose 5-phosphate followed by loss of TPP ylide to give sedoheptulose 7-phosphate. Show the mechanism.arrow_forwardThe vitamin Niacin is used to form nicotinamide adenosine dinucleotide, which readily shuttles between its oxidized (NAD+) and reduced (NADH) forms. The latter serves as a cellular equivalent to NaBH4. The essential portions of the structures are shown below. Outline a mechanism for the cellular conversion of pyruvate to lactate. (Note: like NaBH4, NADH cannot reduce carboxylic acid carbonyls).arrow_forwardIn the body, during the citric acid cycle the following reaction occurs as the first part of an enzyme mediated process. но OH YYYYYY OH OH H₂O NaBH4 LiAlH4 H₂SO4 and heat K₂Cr2O7 HQ OH What reagent would be used to bring about this reaction in the laboratory? OH 3arrow_forward
- Triosephosphate isomerase (TIM) catalyzes the conversion of dihydroxyacetone phosphate to glyceraldehyde-3-phosphate. The enzyme’s catalytic groups are Glu 165 and His 95. In the first step of the reaction, these catalytic groups function as a general-base and a general-acid catalyst, respectively. Propose a mechanism for the reaction.arrow_forwardIf an enzyme-catalyzed reaction has a high rate at low pH and low rate at higher pH, this implies that a group on either the enzyme or the substrate must be for an efficient reaction. leaving group oxidoreductase coenzymes O protonated deprotonated The compound that consists of deoxyribose linked by an N-glycosidic bond to N-9 of guanine is: adenylate deoxyguanosine guanosine nucleotide guanylatearrow_forwardWhy has triglyceride autooxidation occurred selectively to give the following product? QOH O This peroxide is the most stable option. O That position is the least crowded. O Allylic H atoms are easier to abstract than alkyl. O Oxygen is a selective diradical.arrow_forward
- What advantage does the enzyme gain by forming an imine?arrow_forwardWhich coenzyme is responsible for the following reaction? CO,H CO,H OH HO.. ОН ОН ОН O TPP (thiamine pyrophosphate) O NAD* (or NADP*) Ο ΚΗ2 O FADH2 В12 O PLP (pyridoxal phosphate) O one of the THE (tetrahydrofolate) coenzymes O NADH (or NADPH) O biotin O FADarrow_forwardImidazoleglycerol‑phosphate dehydratase is an enzyme in the histine biosynthesis pathway. It catalyzes the E1 dehydration of D‑erthyro‑imidazole‑glycerol phosphate to imidazole acetol‑phosphate. This is a rare example of a biological E1 reaction, as most biological elimination reactions occur through E1cB instead. In this reaction, D‑erthyro‑imidazole‑glycerol phosphate is first protonated to form a good leaving group. Then, the leaving group is ejected to form the resonance‑stabilized carbocation shown. Draw curved arrows forming the most stable resonance structure to explain why this reaction goes through an E1 mechanism. Draw curved arrows to form the most stable resonance structure.arrow_forward
- ter 18 em 18.18 Part A What coenzyme picks up hydrogen when a carbon-oxygen double bond is formed? Express your answers as a chemical expression. ΑΣΦ Submit Previous Answers Request Answer X Incorrect; Try Again; 3 attempts remalning ide Feedback (१ ।arrow_forwardLysine catabolism begins with reductive amination of a-ketoglutarate to give saccharopine in a multistep process. Draw curved arrows to show the movement of electrons in this step of the reaction mechanism. Arrow-pushing Instructions 7 COO H NH3 COO OOC B: COO H NH3 COO BH+arrow_forwardHow would you describe the glycosidic bond in the following molecule? OH OH HOH H 0- H. но H ОН Он Н H OH OH H. alpha-1,4- beta-1,4- alpha-1,6- beta-1,6- none of thesearrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Introduction to General, Organic and BiochemistryChemistryISBN:9781285869759Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar TorresPublisher:Cengage Learning
Introductory Chemistry: A FoundationChemistryISBN:9781337399425Author:Steven S. Zumdahl, Donald J. DeCostePublisher:Cengage Learning
Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning
Introduction to General, Organic and Biochemistry
Chemistry
ISBN:9781285869759
Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar Torres
Publisher:Cengage Learning
Introductory Chemistry: A Foundation
Chemistry
ISBN:9781337399425
Author:Steven S. Zumdahl, Donald J. DeCoste
Publisher:Cengage Learning
Organic Chemistry
Chemistry
ISBN:9781305580350
Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher:Cengage Learning
DIGESTER-35 | VITAMINS AND THEIR RELATED COENZYMES| GPAT | NIPER | PHARMACIST| DI; Author: GPAT DISCUSSION CENTER;https://www.youtube.com/watch?v=CGrdNYmho0s;License: Standard YouTube License, CC-BY