Book review

Authors


Fundamentals of Enzyme Kinetics, 4th EditionAthel Cornish-Bowden, Wiley-Blackwell, 2012, 510 pp., ISBN 978-3-527-33074-4 (Paperback $79.95).

Henry Jakubowski*, * Chemistry Department, College of Saint Benedict/Saint, John's University, Saint Joseph, Minnesota 56374.

Enzyme kinetics comprises the major quantitative part of a typical biochemistry course, but as it is usually compartmentalized into a few chapters of a giant tome, it can be tempting for students to either dismiss or not fully appreciate its usefulness in helping investigators decipher and understand biomolecular interactions. It is hard to convey to students, how much kinetic analyses, which require little more than a crude enzyme, a stopwatch, and a collection of substrates and potential inhibitors, can illuminate our understanding of biological processes. What a pity since without an understanding of the kinetic equations and rate constants that characterize simple and complex enzyme-catalyzed reactions, how can students ever hope to really cope with modeling the complexities of biological systems controlled by intertwined signal transduction networks? Any book that provides those who teach or perform enzyme kinetics with reinforcing and strengthening insight and guidance, and that also provides clear and new examples for use in teaching or research is very welcome.

Athel Cornish-Bowden's latest edition (4th) of Fundamentals of Enzyme Kinetics does all that and more. In the preface, Cornish-Bowden states that his goal is to provide an understanding of enzyme kinetics, not an encyclopedic coverage of this field. This edition is a complete revision and expansion of earlier versions done in part make it “user friendly” in its style and organization. He succeeds in both tasks. This is a great book for advanced undergraduate students, and for graduate students, faculty, and researchers who truly wish a deeper understanding of this field.

From an organizational perspective, the book is a treat. It is extremely readable. Chapter 1 presents a clear review of chemical kinetics for reactions not catalyzed by enzymes, and is followed by Chapter 2 entitled Introduction to Enzyme Kinetics. Noting that a great deal of the theory of enzyme kinetics was developed before a clear indication of the chemical nature of the catalyst, he next presents a brief foray into “alternative” enzymes, including abzymes, ribozymes, and synthetic catalysts. Chapter 4 then deals with practical aspects of kinetics. A very lucidly written explanation of the use of the King–Altman method in deriving steady state rate equations is laid out in Chapter 5, complete with an optional section on the use of determinants in deriving King–Altman patterns. Subsequent chapters cover all the important areas of enzyme kinetics including enzyme inhibition and activation, multi-substrate reactions, pH and isotope effects, and enzyme regulation. He concludes with two important chapters on fast reactions and one that covers “data analysis in an age of kits” which gives a much needed explanation of error analysis. Each chapter ends with bulleted summary points and problems with answers provided at the end of the book.

What enhances its readability is Cornish-Bowden's decision to expand the number of figures and tables, and to place many of them, along with references, in the margins of the page corresponding to the written explanations of the figures. The abundance and placement of figures make this book unique and highly effective in leading readers to the understandings he wishes us to achieve. The author has included many graphs consisting of straight line transformations of nonlinear equations, which he argues in his preface allows visible expression of “unseeable” experimental data in ways that computer fitting of data does not easily allow.

It is in the understandings provided by the written explanations with support from clear figures that the book shines. He peppers the book with many examples of common misinterpretation and misuses of kinetic data and their transformations. In Chapter 2, he shows how many textbooks misdraw the hyperbolic dependency of initial velocity on substrate concentration, which gives the false impression that saturation of an enzyme is readily achieved and that Vmax is readily determined. He also takes umbrage at the use of Vmax, as the graph of vo versus S reaches a mathematical limit, not a mathematical maximum. Hence, he drops subscripts for velocity terms and uses v and V to represent the initial velocity at any substrate concentration and limiting velocity at saturating values of substrate, respectively, while retaining the “M” in the Michaelis constant, KM. Likewise, he gives an excellent description of the specificity constant, kcat/KM, as the ratio of second order rate constants for competing substrates that are both simultaneously present, a physiologically relevant definition as enzymes do “encounter” this scenario.

Also in Chapter 2, the author describes the strengths and liabilities, as well as the historical development, of graphs of v versus A, v versus log A, and linear transformations of the Michaelis–Menten equation. He also has a nice review of progress curve analysis in the presence and absence of product inhibition and explains in clear detail the problems with using this method. For example, he discusses how large errors in V and Km will occur if factors other than product inhibition (such as small losses of enzyme activity or changes in pH or temperature during the measurements occur). It would have been beneficial if he had included a critical review of the recent use of Lambert functions which give product concentration as an explicit function of substrate concentration and allows for determination of kinetic constants in a single time course.

The book offers much practical advice. For example in Chapter 4, the author describes straight forward ways to detect changes in enzyme activity during an assay, an occurrence which if unrecognized can wreck the best assays and subsequent analyzes. He notes that investigators cannot assume that site-directed mutants retain their activity during the course of an assay as laboratory selection for an altered activity is quite different from natural selection used in the evolution of wild type enzymes. He gives an excellent explanation of the difficulties in estimating initial rates and the biases in doing so that skew their accurate determination. Nothing is arguable more important to practitioners whose entire analyzes would be nullified by inaccurate determination of initial rates.

Chapter 6 deals with reversible inhibition and activation. Noncovalent reversible inhibition is discussed in all undergraduate biochemistry classes. Those who use Cleland's nomenclature for inhibition constants (Kis where s represents a change in the slope of a double reciprocal plot characteristic of competitive inhibition and Kii where i represents the change in the intercept of the plots, found in uncompetitive inhibition) might be pleased to change to the subscripts used by Cornish-Bowden (Kic for competitive inhibition where inhibitor binds to free E and Kiu for uncompetitive where inhibitor binds to enzyme–substrate complex). He goes through a clear treatment of plotting inhibition data, and the relationship between IC50 values and calculated inhibitor dissociation constants for competitive, uncompetitive, and mixed inhibition. As he indicates a heightened need for an understanding of enzyme kinetics in biotechnology and drug design, he devotes part of Chapter 7 to drugs as inhibitors and notes, as he has done in previous papers but which is not discussed in biochemistry textbooks, that inhibition of pathways in vivo is best effected under conditions of constant flux by uncompetitive inhibitors of key central enzymes in the pathway.

I could continue with his excellent treatment of multisubstrate reactions and other topics in the second half of the book. I again note the excellent chapter on error analyses at the end of the book. Without knowing the significance of the fit parameters, how can one have confidence in the calculated kinetic parameters or in the explanatory kinetic models? His own errors are on his mind as well as he has provided a list of corrections for his book at http://bipcnrs-mrs.fr/bip10/fek.htm. In addition, he has provided a companion website at http://www.wiley-vch.de/home/fundenzykinet which gives a link to Supporting Information from which all figures and tables can be downloaded for teaching purposes.

This book is a gem. The writing is clear and concise. It is filled with historical information, hints, common errors of analysis, and enough theory to enable his readers to do what Cornish-Bowden really wants, which is to understand, perform, and interpret enzyme kinetic analyses correctly and in a way which unleashes the explanatory power derived from their sound use.

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