loncapadcmcb:uiuc - MCB 354 Fall 2020 1Exam IIWhich carbon in the following nucleoside is the anomeric carbon?A. BB. AC. CD. DE. ETries 0/99loncapadcmcb:uiuc - MCB 354 Fall 2020 2Exam IIBelow is an image of deoxygenated hemoglobin showing a salt-bridge between Glu-43 and Arg-92 of the beta and alphasubunits, respectively. If Arg-92 is mutated to alanine, what is the most likely effect on the Hill coefficient and K0.5?A. Both will decrease.B. Both will increase.C. K0.5will increase and nHwill decrease.D. K0.5will decrease and nHwill increase.Tries 0/99loncapadcmcb:uiuc - MCB 354 Fall 2020 3Exam IIWhat is the glycosidic bond in the following disaccharide?A. beta2-beta2B. alpha2-3C. beta2-3D. beta1-3E. beta2-beta1Tries 0/99Which enzyme is specific to the liver?A. Glucose-6-phosphataseB. Glycogen phosphorylaseC. Glycogen synthaseD. HexokinaseE. Glycogen alpha1-6 branching enzymeTries 0/99loncapadcmcb:uiuc - MCB 354 Fall 2020 4Exam IIFurin is a protease in the endoplasmic reticulum that is important for proteolytic maturation of many proteins,including the viral spikes of HIV and SARS-CoV-2. Below is shown an electrostatic surface of furin, with acidicresidues in red and basic residues in blue. A bound substrate is yellow, with side chains occupying specificity pockets.Which homo-oligopeptide is most likely to be a substrate of furin?A. RRRRRRRRB. FFFFFFFFC. EEEEEEEED. NNNNNNNNE. SSSSSSSSTries 0/99loncapadcmcb:uiuc - MCB 354 Fall 2020 5Exam IIBelow is the active site of the protease encoded by the SARS-coronavirus-2 genome. Carbons of the protein arecolored tan, while carbons of a bound irreversible inhibitor are colored pale green. Nitrogens are blue, oxygens arered and sulfurs are yellow. What is the role of S144?A. To stabilize the transition state.B. To donate electrons.C. To act as a general acid-base.D. To act as a nucleophile.E. To modulate pKa of H41.Tries 0/99loncapadcmcb:uiuc - MCB 354 Fall 2020 6Exam IIThe hydropathy plot of MalK, a subunit of the ABC transporter that catalyzes maltose import, is shown below. Howmany transmembrane helices does MalK have?A. 7B. 5C. 6D. 8E. 9Tries 0/99loncapadcmcb:uiuc - MCB 354 Fall 2020 7Exam IIWhich image correctly shows the molecular structure of ribose-(beta1-3)-deoxyribose?A. CB. AC. BD. DTries 0/99Which statement is false?A. The NaK pump is an example of a secondary active transport system.B. The NaK pump exports 3 Na+ions for every two K+ions imported.C. ABC transporters use the energy of ATP binding and hydrolysis to drive conformational changes.D. A coupled transporter that moves two solutes in opposite directions is an antiporter.E. For a noncooperative transporter, transport velocity increases with an approximate first order rate law at lowconcentration gradients (less than the KM).Tries 0/99loncapadcmcb:uiuc - MCB 354 Fall 2020 8Exam IIWhat is the following lipid?A. CeramideB. PhosphatidylserineC. PhosphatidylcholineD. SphingosineE. CerebrosideTries 0/99Furin is a very important protease that processes many secreted and membrane proteins. It is synthesized with aninhibitory prodomain that must be proteolytically excised by autocatalysis. This is an example of:A. A zymogenB. Burst phase kineticsC. Product inhibitionD. Negative allosteryE. Positive heterotropic cooperativityTries 0/99Patients with glycogen storage disorder type IX have a deficiency in the enzyme glycogen phosphorylase kinase. Thereare both muscle and liver specific forms. In the liver specific form of the disease, which is false?A. Glycogen phosphorylase is hyperphosphorylated.B. There is an accumulation of glycogen in the liver.C. There is hypoglycaemia (low blood glucose).D. There are elevated levels of blood ketones, produced from oxidation of fats for energy.Tries 0/99Silanediols are transition state analogues of aspartyl proteases, such as HIV protease. One particular silanediol interactswith HIV protease with KD= 1.2 nM. In the pr esence of 2.4 nM silanediol, how will protease activity change?A. KMincreases by 3-foldB. KMincreases by 2-foldC. Vmaxdecreases by 2-foldD. Vmaxdecreases by 3-foldE. Both KMand Vmaxdecrease by 2-foldTries 0/99loncapadcmcb:uiuc - MCB 354 Fall 2020 9Exam IICFTR is a chloride channel that is mutated in cystic fibrosis. CFTR is also structurally homologous to ABC trans-porters. Purification of CFTR r equires:A. Detergent extractionB. Chaotropic agents like ur eaC. Chelating agents like EDTAD. Elevated pH to deprotonate basic/positive patches on the protein surfaceE. Phospholipase A2Tries 0/99The enzyme HarryPotter-1 (HP-1) catalyzes the hydrolysis of the potion Severus. It is inhibited by the small moleculeNimbus. The catalytic activity of HP-1 was measured in the absence and in the presence of 1.3 nM Nimbus and istabulated below. What kind of inhibitor is Nimbus?[Sever us] (µM) V0(µM/min) V0(µM&#47min) with 1.3nM Nimbus0.5 0.66 0.541 1.1 0.812 1.8 1.14 2.5 1.3A. AnticompetitiveB. IrreversibleC. CompetitiveD. NoncompetitiveE. Mixed inhibitorTries 0/99What is the Kiof Nimbus for inhibiting HP-1?A. 0.9 nMB. 0.3 nMC. 0.5 nMD. 0.7 nME. 1.1 nMTries 0/99loncapadcmcb:uiuc - MCB 354 Fall 2020 10Exam IIHemocyanin (Hc) is an oxygen-carrying protein usually found in the hemolymph of crustaceans, but is also found insome insects that live in hypoxic environments (for example, aquatic environments). Hc of the stonefly Perla marginate,which has a semiaquatic lifestyle, has a Hill coefficient of 1.9 and is half-saturated with O2at 8 torr. If the O2partialpressure is 16 torr, what is the fractional saturation of Hc?A. 79%B. 50%C. 67%D. 21%E. 97%Tries 0/99Etanercept (sold under the brand name Enbrel) is a soluble decoy receptor for TNFalpha. It is used in the treatmentof autoimmune diseases. The KDfor noncooperative binding of etanercept to TNFalpha is 1.2 pM. What fraction ofTNFalpha is sequestered if the serum concentration of etanercept is 18 pM?A. 94%B. 77%C. 6%D. 99%E. 62%Tries 0/99Which of the following is not an allosteric modulator of phosphofructokinase-1?A. Fructose-2-phosphateB. ATPC. PhosphpoenolpyruvateD. CitrateTries 0/99Which of the following statements about chymotrypsin is false?A. Burst phase kinetics are observed due to a slower acylation phase.B. An oxyanion hole s tabilizes negative charge on the oxygen of the scissile amide bond.C. An acyl-enzyme intermediate is formed.D. An aspartate modulates the pKa of a histidine acting as a general acid-base.E. The reaction pro ceeds through tetrahedral, oxyanion intermediates.Tries