(a) Write down the reaction of phosphatidylcholine (PC) cleaved by PLA2. Suppose the two acyl groups are R1 and R2 as shown in the figure. Make sure the chiral carbons in the reactions have the right stereochemistry (i.e., use wedge-dash notation), and the charges on the atoms reflect the molecule in neutral pH.

(a) Write down the reaction of phosphatidylcholine (PC) cleaved by PLA2. Suppose the two acyl groups are R1 and R2 as shown in the figure. Make sure the chiral carbons in the reactions have the right stereochemistry (i.e., use wedge-dash notation), and the charges on the atoms reflect the molecule in neutral pH.

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter6: Energy, Enzymes, And Biological Reactions

Section: Chapter Questions

Problem 8TYK: Which of the following statements about the allosteric site is true? a. The allosteric site is a...

See similar textbooks

Similar questions

Figure 16.13 An increase in phosphorylation levels of elF-2 has been observed in patients with neurodegenerative diseases such as Alzheimer’s, Parkinson's, and Huntington's. What impact do you think this might have on protein synthesis?
Which of the following statements about the allosteric site is true? a. The allosteric site is a second active site on a substrate in a metabolic pathway. b. The allosteric site on an enzyme can allow the product of a metabolic pathway to inhibit that enzyme and stop the pathway. c. When the allosteric site of an enzyme is occupied, the reaction is irreversible and the enzyme cannot react again. d. An allosteric activator prevents binding at the active site. e. An enzyme that possesses allosteric sites does not possess an active site.
The allosteric regulation of ATCase by CTP is an example of: 1. Negative homotropic allostery 2. Positive homotropic allostery 3. Negative heterotropic allostery 4. Positive heterotropic allostery
A chain NH3 NH3 B chain Gly Phe 2. The protein pictured below is bovine insulin. Determine the number and the size of the fragments that would be generated upon treatment with the following: İle Val Val Asn Gln Gln 5 Ġln 5 His look for the cleavage points (a) without DTT and (b) with DTT. Cys Leu Cys S-S Cys Without DTT With DTT Ala Ģly Ser Ser Trypsin 10 Val 10 His Cys Leu Chymotrypsin Ser Val Leu Glu BrCN Tyr Ala 15 Gln 15 Leu Leu Тyr Ġlu Leu Ásn Val Тyr Cys 20 Çys 20 Gly Asn Glu Arg Reagent (source) Trypsin (bovine pancrease) Chymotrypsin (bovine pancrease) Staphylococcus V8 protease Pepsin (porcine pancrease) Cyanogen bromide (chemical)(CnBr) Specificity Lys, Arg (C) Phe, Trp, Tyr (C) Glu, Asp (C) Phe, Trp, Tyr (N) Met (C) Gly Phe 25 Phe Тyr Thr Pro Lys 30 Ála
2. The diagram to the right shows the change in the structure of the C-terminal portion of each of the ẞ-subu- nits of human hemoglobin (HbA) in the oxyHb to deox- yHb or R-to-T transition. The hydrogen bonding interac- tion of the C-terminal ẞHis 146 residue with the side chain of Asp94, highlighted by the red ellipse, has been shown to be responsible for a major portion of the proton uptake associated with the Bohr effect. Treatment of HbA with the enzyme carboxypeptidase A (CPA) results in loss of the C-terminal ẞHis 146 and ẞTyr145 residues of the ẞ- subunits. (a) ( ) Draw a Hill plot [log(Y/[1-Y]) vs. log(pO2), Y = fraction of heme groups occupied by O2] to compare the values of the Hill coefficient nн and the O2-binding affinity at pH 7.4 of normal HbA before and after treat- ment of with CPA. (b) (' ) How will the plot for CPA-digested HbA change at pH 7.2? (c) 1 Hi5146 HN- ✓ Low PK B-chain. CH2 CH-NH-CO-CH-NH- CH₂ Tyr145 он HbO2 or R state Туг145 CH-CH2- OH co NH CH CH₂ His…
5. Protein phosphatase 1 (PP1) is a major eukaryotic serine/threonine protein phosphatase that regulates many diverse cellular processes. One study has shown that phosphatidic acid (PA) is an inhibitor of PP1. The investigators measured the activity of PP1 in the presence and absence of the inhibitor PA. The concentration of PA was 300 nM. [Substrate] (µM) Vo with PA (µM sec-1) 0.00381 Vo without PA (µM sec-1) 0.010 0.0209 0.015 0.0335 0.00620 0.025 0.0419 0.00931 0.050 0.0838 0.0140 a. Use Excel to make a Lineweaver-Burke plot showing both the noninhibited and the inhibited reactions. Your Lineweaver-Burke plot should have labeled axes with units. The graph should display both the y-intercept and the x-intercept and include linear trendline equations. b. Determine Vmax and Km for the enzyme in the uninhibited state. Be sure to include your units. c. Determine the type of inhibition for this inhibitor PA. Briefly explain. d. Calculate the K¡ for the inhibitor PA.
Protease enzymes cleave proteins by hydrolyzing peptide bonds. The strategy for each type of metalloprotease begins with generating a nucleophile that attacks the peptide bond that attacks the peptide carbonyl group. O Macmillan Learning On the basis of the information provided in the figure, show the next step in the mechanism for peptide-bond cleavage by a metalloprotease. Metalloproteases H R₁ HN Zn Enz 2+ R₂ Draw curved arrows on the pre-drawn structures to show the metalloprotease mechanism. If you need to reset the structures, click More followed by Reset Drawing. Select Draw Templates Groups More B - H Enz H H с R1 | : HN O | Zn 2+ B R2 N Zn Erase
The enzyme cytidine deaminase catalyzes the conversion of cytidine to uridine. Cytidine deaminase catalyzes the reaction through an addition of water across the cytidine 3,4-bond, forming a tetrahedral intermediate followed by the elimination of NH3 to form the product uridine. This is like the addition-elimination mechanism that we studied for adenosine deaminase. Cytidine deaminase НО. NH₂ N пOH OH cytosine R + H₂O cytidine The Km value for the substrate cytidine is 2.5 × 10-4 M, and the K; for competitive inhibition by the product uridine is 2.5 × 10-³ M. N R A reduced derivative of the product, 3,4,5,6-tetrahydrouridine was shown to be a fully reversible competitive inhibitor with a Ki of 2.4 x 10-7 M, a value approximately 10,000 times lower than that of the product uridine. NH₂ NH uridine HO. N R R = D-ribose HOH OH uridine 3NH uracil ring numbering H NH H H + NH3 H OH H 3,4,5,6-tetra- hydrouridine a.) Draw a structure of the intermediate that we predict to form during the…
3. Suggest a role for ActA in addition to Arp2/3 complex mediated actin polymerization. Extend the watermelon seed analogy used in the lecture. Compare wild-type Listeria with the ActA mutant. If the watermelon seed is Listeria and your fingers are a comet tail, what would the outcome be when squeezing your fingers when using wild-type Listeria, what would you expect when using the mutant? Answer Here: One role for ActA in addition to Arp2/3 complex mediation
3. Solve the sequence of an oligopeptide 7 residues long which gave: Asp Leu Lys Met Phe Tyr The following facts were observed: a. Trypsin treatment had no apparent effect b. The PTH derivative from Edman degradation was c. Brief chymotrypsin treatment yielded several products including but not limited to a dipeptide and a tetrapeptide. The amino acid composition of the tetrapeptide was Leu, Lys, and Met. d. Cyanogen bromide treatment yielded a dipeptide, a tetrapeptide, and a free Lys.
3. Solve the sequence of an oligopeptide 7 residues long which gave: Asp Leu Lys Met Phe Tyr The following facts were observed: a. Trypsin treatment had no apparent effect b. The PTH derivative from Edman degradation was c. Brief chymotrypsin treatment yielded several products including but not limited to a dipeptide and a tetrapeptide. The amino acid composition of the tetrapeptide was Leu, Lys, and Met. d. Cyanogen bromide treatment yielded a dipeptide, a tetrapeptide, and a free Lys. Instructions Make use of the table below to determine the sequence of the mystery protein.
6)During the epinephrine signaling pathway we learned about in class, the enzyme glycogen phosphorylase is regulated by: Zymogen activation Competitive inhibition Allosteric regulation Covalent modification