l Citric acid cycle 1_ Pyruvate formation

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1 Chemistry 255 (Fal115) Name S 1-...e.pha.., CCrrt Exam 2 (So pts) 1. (5 pts) List the order of the metabolic events from start (#1) to fmish (#5): A TP produced in Glycolysis l Citric acid cycle 1_ Pyruvate formation Fructose 6 Phosphate is converted to Fructose 1,6-Bisphosphate by PFK _!_Glucose is Phophorylated by ATP 2. (2 pts) Which enzyme is present when ATP phosphorylates glucose to form glucose-6-phosphate. a. glucose dehydrogenase (ii) hexokinase c. glucose protease d. isomerase e. glycogenphophorylase 3. (2 pts) Which type of enzyme facilitates the hydrolysis of a protein to simple amino acids a. kinase (l)protease c. dehydrogenase d. isomerase e. lysozyme,.s".tju,o... su6uin 4. (4 pts) State if the processes below are Anabolic (A), or Catabolic (C) a. The Citric acid cycle C. b. Fructose bis Phosphate (FBP) converted to 2 GAP molecules during glycolysis c. Protein hydrolysis C. d.. Glucose molecules combining to form Starch and glycogen_a 5. (3 pts) What is true about the metabolism of Fructose (circle all that apply). a. Does not enter glycolysis-goes directly to the Citric Acid cycle. b. Cannot be phosphorylated by ATP in the muscle. (9 Enters glycolysis as glyceraldehydes-3-phosphate (GAP) when broken down by the Liver d. Will be converted into High Fructose Com syrup. (Dean be used to synthesize fats when processed in the Liver. 6. (5 pts). Circle the following statement(s) that are true about metabolic flux control? a. c. Flux control will only occur in reactions where the.6.g value is near. Flux control will occur when reactions have a large -.6.G value Enzymes have nothing to do with Flux control Allosteric inhibition of an Enzyme can control flux Covalent modification of the enzyme can control flux: It is common for Products of a reaction to act as allosteric inhibitors of the reaction.

2 7. (6 pts) Name the 3 structures below (you can use their abbreviated names as well) H cy -d o-o o" o(x). I -dn N -o-- H H H. H H Name._N : A:.:::b: :t 8. (3 pts) Show the product of hydrolysis of Acetyl CoA.. -. <"X: r /? o o II II NH 2 N N) CH3 S,./'... U - O-P-O-P--d Y... 'NN I I H H o- o- H H Acetyl-coenzyme A (acetyl-coa) H H

3 Answer questions 9-17 pertaining to reactions #1-#4 (shown below). For questions 9-12, when drawing products that are large such as A TP, NADH, CoA etc you can simply write their abbreviations. REACTION#l Y%> + Reagent 'A'.. g product 'B' + NADH REACTION# NAD+ 2 Products + C 2 REACTION#3 e (\./""' eo,,...o. o,( + ADP --- o-p - II o 2 Products REACTION#4 e o Jl o CH{' (( + CoASH + NAD+ 3 Products 9 (4 pts) For reaction #1, Draw Reagent 'A" and product "B" in the space below oj NAD "tl)\,e t8 c.dv,'c auj c'jcl... $1 1 (4 pts) For Reactions #2 draw the 2 products formed in the space below 11. (4 pts) For reaction #3 draw the 2 products formed e OI-l ',.6'.1 r.)e-t e l(t> + (;TP C) 12 (5 pts) For reaction #4 draw the 3 products formed II LH'3,..c.--:.-Co... /v})h -1- (-z_., A<.41- c, A 'f 13. (2 pts) Which reaction (#1-#4) above uses a multienyme complex? 14. (2 pts) Which reaction(s) (#1#4) are part of the citric acid cycle? (._z.._(_tt_ls_,_ll_o.--,c),- 15. (2 pts) Which reaction(s) (#1-#4) are part ofglycolysis? (2 pts) Which reaction(s) (#1-#4) would use a 'dehydrognease' as an enzyme? 17. (2 pts) Which reaction(s) (#1-#4) would use a Kinase as an enzyme?_--=3---'-{--=-"_, 4..1+h AJP j 1,2., t( (a"'tj l.tj)'naps>l NIJIJ)

4 Bonus Points: (8 pts) In the space below, draw the arrow pushing mechanism for Reaction #2 REACTION#2 t.jojj )I N }l +(] N It- ' 18. (3 pts) The Michaelis-Menten equation is the basic equation for enzyme kinetics. Vo = Vmax [S] I KM + [S] Briefly state what the KM, the Michaelis-Menten constant, pertains to within an enzyme mediated reaction. Kin fu.ns-er!h -fk.,_ BmJ,., 3 "(flu.-- 'in"j';jfflt -S.I..,1tA Cor-r-.plex{_fs J t<,.. = Z_g] [s] A Srnctll j::: ri\ia>'ij St'h"'d Y3mr,tnJ _,. fc.rl A.Jlw, (Lt..fL V6 If k..., /J _,.Smt1 19. Below is Lineweaver-Burke data for the phosphorylation of galactose by the enzyme hexokinase. An experiment used mannose as the substrate instead of galactose it was found that the enzyme bound more tightly to mannose than galactose but that the V max value was the same value. a. (3 pts) Given the information above, draw the data plot for hexokinase with mannose. b. (2 pts) Which substrate (galactose or mannose) has a faster rate of reaction? JhA"""I.A- 'Hos lfey bn.j'(/ fo e, 111'1\9- lno { hexokinase with galactose '(\"\\,fa:/ b r.j'(\f l<: Snal\U "" f,t W'""'"' S \ r 1/[S] -'/K h (l1blfl'l yffl Pin fll> r;..v h.,..s e;llt>lc.l S/o--{;. t f'y r-x tl

5 2. 7 pts (1 pt each) Below is a schematic of the enzyme glycogen phosphorylase a and b which is responsible for Glycogen breakdown to Glucose- 1-phosphate. Note that the heavier equilibrium arrow show to where the equilibrium is favored. For the statements below state whether they are True or False regarding the enzyme glycogen phosphorylase a and band its catalysis of Glycogen breakdown to Glucose- 1-phosphate. 6;1or F) A TP is allosteric inhibitor of this reaction (T ol(f) AMP is an allosteric inhibitor of this reaction (To A TP binding to phosphorylase b is an example of covalent modification (r>or l) The Conversion of phosphorylase a to phosphorylase b is an example of covalent modification (To High glucose concentrations should activate/accelerate the Glycogen breakdown to Glucose- 1-phosphate. O}>r F) The activity of the enzyme phosphorylase kinase should activate the Glycogen breakdown to Glucose- F) The activity of the enzyme phosphoprotein phosphatase should deactivate the Glycogen breakdown to Glucose-!-phosphate Tfonn (inactive) 2ATP ':::shory:ej krnase '. phosphopr f',...hosphatase 2P; 2H 2 ATP and/or G6P AMP Glucose Rform (active) Phosphorylase b C 28 John Wiley & Sons, In All rights rtierved. Phosphorylase a 8 a. (3 pts) For the disaccharide below circle all anomeric carbons and describe the glycosidic link (i.e. a (1-4)). b. (3 pts) If this disaccharide was hydrolyzed with the appropriate enzyme what would be the product(s) of this reaction. L'"""8 Extra Credit (1 pt) What was your favorite poster from the posters sessions last week (both title and students who produced it if you can remember...) _ 1 Clio\..pc,. 1' CN) " 'f'-p"f t;...(,j"s IC- l!