Molecular Biochemistry I

Glycolysis and Fermentation

Reading:

Textbook Reading: Voet & Voet, Biochemistry, 3rd Edition, Chapter 17.

Some recent articles (optional reading): 
X. Liu, C. S. Kim, F. T. Kurbanov, R. B. Honzatko & H. J. Fromm (1999) "Dual mechanisms for glucose 6-phosphate inhibition of human brain Hexokinase," J. Biol. Chem. 274: 31155-31159.
N. de la Iglesia, M. Mukhtar, J. Seoane, J. J. Guinovart & L. Agius (2000) "The role of the regulatory protein of glucokinase in the glucose sensory mechanism of the hepatocyte," J. Biol. Chem. 275: 10597-10603.
R. K. Wierenga (2001) "The TIM-barrel fold: a versatile framework for efficient enzymes," FEBS Lett. 492: 193-198.
N. Nagano, C. A. Orengo & J. M. Thornton (2002) "One fold with many functions: the evolutionary relationships between TIM barrel families based on their sequences, structures and functions," J. Mol. Biol. 321: 741-765.
M. E. Munoz & E. Ponce (2003) "Pyruvate kinase: current status of regulatory and functional properties," Comp. Biochem. Physiol. Part B 135: 197-218.
L. B. Gladden (2004) "Lactate metabolism: a new paradigm for the third milllennium," J. Physiol. 558: 5-30.
J. A. Gerlt, P. C. Babbitt & I. Rayment (2005) "Divergent evolution in the enolase superfamily: the interplay of mechanism and specificity," Arch. Biochem. Biophys. 433: 59-70.
J.-W. Kim & C. V. Dang (2005) "Multifaceted roles of glycolytic enzymes," Trends in Biochem. Sci. 30: 142-150.
A. Philp, A. L. Macdonald & P. W. Watt (2005) "Lactate - a signal coordinating cell and systemic function," J. Exptl. Biol. 208: 4561-4575.
R. Dentin, J. Girard & C. Postic (2005) "Carbohydrate responsive element binding protein (ChREBP) and sterol regulatory element binding protein-1c (SREBP-1c): two key regulators of glucose metabolism and lipid synthesis in liver," Biochimie 87: 81-86.
E. Ghanassia, J.-F. Brun, J. Mercier & E. Raynaud (2007) "Oxidative mechanisms at rest and during exercise," Clinica Chim. Acta 383: 1-20.

Potential Test Questions:

1. Diagram the pathway of Glycolysis from glucose to pyruvate, giving structures and names of all pathway intermediates (enzyme mechanisms not required here) and names of enzymes (no abbreviations). Indicate where ADP, ATP, Pi, NAD+, or NADH is a substrate or product of a reaction.

2. a. List substrates and products for the reaction catalyzed by Phosphofructokinase. 
    b. Diagram and explain the dependence of Phosphofructokinase reaction rate on [fructose-6-phosphate], at low and high [ATP].  Explain the value to a cell of the effect of high [ATP] on Phosphofructokinase. 

3. Indicate one example of a pathway by which the NADH generated in Glycolysis is reoxidized in anaerobic organisms, giving names and structures of reactants and products (reaction mechanisms not required here). Explain why anaerobic organisms, which lack a respiratory chain, must have such a mechanism for oxidizing NADH.

4. a. List substrates and products for the reaction catalyzed by Hexokinase. 
    b. How does the liver Glucokinase enzyme differ from Hexokinase in its dependence on concentrations of reactant(s) and/or product(s)? How is this important to the role of the liver in regulating blood glucose?

Copyright 1998-2007 by Joyce J. Diwan. All rights reserved.

Lecture notes on
Glycolysis

Interactive Quiz on
Glycolysis

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