Consider the following biochemical reaction. pyruvate + CoA-SH Acetyl-CoA + CO2 AG = -175 kJ Select all statements that are true for this reaction. a. This reaction absorbs energy Ob. This reaction must have a transition state OC. This reaction is exergonic Od. This reaction is non-spontaneous

The following two reactions are coupled in the last step of glycolysis (catalyzed by the enzyme pyruvate kinase). РЕР + Н.О € Руr + Pi ADP + Pi → ATP + H2O AG° = -14.8 kcal/mol AG° = +7.3 kcal/mol D) The steady-state concentrations of ATP, ADP, and pyruvate in human erythrocytes are 2.24 mM, 0.25 mM, and 0.051 mM, respectively. What would be the concentration of PEP in these cells if the coupled reaction was at equilibrium?

GAP + Pi + NAD+ ⟹1,3-BPG + NADH (Reaction 1)      1,3-BPG + ADP  ⟹ 3-PG + ATP (Reaction 2) Which of the following statements concerning the information above is true? Select all that apply. A.Reaction 2 is an example of substrate level phosphorylation B.These reactions are written in a direction that would indicate gluconeogenesis is occurring in the liver C.The linking of Reaction 1 and Reaction 2 by the intermediate 1,3-BPG is an example of coupling of reactions D.Reaction 1 shows a redox reaction where the carbon skeleton is oxidized to generate electrons for a soluble electron carrier E.These reactions are irreversible under cellular conditions

9. The equation below depicts the first step of the citric acid cycle. H0 CoA-SH CH-C + 0=C-CO0 HO C-COO citrate s-COA ČH2-COO synthase ČH2 -CO0 Citrate Acetyl-CoA Oxaloacetate AG" = -32.2 kJ/mol a) Explain the chemical conversions that take place during this step. b) Why is this reaction energetically favorable? Explain.

The following reaction, the last reaction in beta-oxidation, is an example of a: Enzyme Enzyme-H S-CoA S-COA H2C H3C CoA s–CoA C H2 CH2 R S-COA S-COA S-COA O A. Nucleophilic acyl substitution O B. Electrophilic addition OC. Nucleophilic addition D. Aldol condensation O E. Hydrohalogenation

The following incorrect description of the HMS path is () A, 6-P-glucose can be converted into pentose phosphate through this pathway B. Four-carbon and seven-carbon sugars can be provided through this route C. For every mole of carbon dioxide produced when 6-P-glucose is converted to pentose phosphate, it also produces 1 mole of NADPH D, 6-P-glucose is decomposed in this way without consumption of ATP Among the following enzyme-catalyzed reactions that can generate substrate level phosphorylation to generate GTP are () A, hexokinase B, enolase C, succinate thiokinase D, succinate dehydrogenase The limiting factor of fatty acid synthesis in cell fluid is (). A, condensation enzyme B, hydration enzyme C, lipoacyl group transferase D, acetyl-CoA carboxylase Which of the following amino acids is an essential amino acid? () A.Thr B.Lys C.Met D.Arg

Provide a reasonable step-wise mechanism for the reaction below, involving TPP as acoenzyme (can abbreviate the pyrophosphate as R), and invoking any general acids or base fromacetolactate synthase that you might need .

Consider the following equilibrium at 298 K. R=8.314 J/K-mol Acetyl-CoA + Oxaloacetate + H20 Citrate + COASH + H* Which one of the following is the correct value for K'eg ifAG" = -32.2 kJ/mol? O 1.11 0.987 1.01 x 10-13 13.0 9.92 x 1012 2480 4.42 x 105 2.27 x 10-6 1.01 -2480 2.56 -13.0 1.08 -0.0130 0.0130 0.926