418 Thermodynamics of Enzyme Reactions /22 : 6 



most rate constants should have an exponential dependence on tempera- 

 ture. A graph of the natural logarithm of the rate constant plotted 

 against 1 jR T is called an Arrhenius plot. The negative of the slope of 

 the resulting straight line is called an activation energy or Arrhenius constant. 

 Reactions in a liquid may be diffusion controlled or diffusion indepen- 

 dent. The last may be treated by the second type of thermodynamic 

 theory called absolute rate theory. It is based on quantum mechanics. 

 It considers any reaction to consist first of the formation of an activated 

 complex and then its dissociation to products. Absolute rate theory 

 interprets the Arrhenius constant as the energy (or enthalpy) necessary 

 to form the activated complex. It allows one to compute an entropy 

 of activation. This leads to consistent values for denaturation reactions, 

 but its meaning is ambiguous in the case of reactions of some heme 

 proteins. 



REFERENCES 



1. Glasstone, Samuel, Textbook of Physical Chemistry 2nd ed. (New York: 

 D. Van Nostrand Company, Inc., 1946). 



2. Eyring, Henry, J. E. Walter, and G. E. Kimball, Quantum Chemistry (New 

 York: John Wiley & Sons, Inc., 1944). 



3. Glasstone, Samuel, K. J. Laidler, and Henry Eyring, Theory of Rate Pro- 

 cesses: The Kinetics of Chemical Reactions, Viscosity, Diffusion, and Electrochemical 

 Phenomena (New York: McGraw-Hill Book Company, Inc., 1941). 



4. Friess, S. L., and A. Weissberger, Technique of Organic Chemistry. Vol. 8. 

 Investigation of Rates and Mechanisms of Reactions (New York: Interscience 

 Publishers, Inc., 1953). 



a. Livingston, Robert, "General Theory of Rate Processes," pp. 1-68. 



b. Livingston, Robert, "Evaluation and Interpretation of Rate Data," 

 pp. 169-230. 



c. Chap. 6: "Reactions in the Liquid Phase," pp. 303-420. 



(1) Leffler, J. E., and Ernest Grunwald: Part 1. "General Methods 

 of Study," pp. 303-335. 



(2) Morse, B. Kathleen, and S. L. Friess: Part 2. "Specific Experi- 

 mental Techniques," pp. 335-420. 



5. Stearn, A. E., "Kinetics of Biological Reactions With Special Reference 

 to Enzymic Processes," Nord, F. F., ed., Advances in Enzymology and Related 

 Subjects of Biochemistry (New York: Interscience Publishers, Inc., 1949) 

 Vol. 9, pp. 25-74. 



6. Ackerman, Eugene, R. L. Berger, and G. K. Strother, "Effects of Tempera- 

 ture on Formation of Intermediate Compound of Catalase With H 2 2 ," 

 Johnson, F. H., ed., Influence of Temperature on Biological Systems (Washington, 

 D.C. : American Physiological Society, 1957) pp. 25-35. 



7. Johnson, F. H., Henry Eyring, and M. J. Polissar, The Kinetic Basis of 

 Molecular Biology (New York: John Wiley & Sons, Inc., 1954). 



