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The chemical kinetics of enzyme action
ARCHIVES
OF RIOCHEMISTRY
AND
BIOPHYSICS
86, 157-160 (1960)
Book The Chemical Kinetics of Enzyme Action. By J. LAIDLER, Professor of Chemistry, The University of Ottawa. Oxford University Press, London and New York, 1958. 419 pp. Price $9.60. KEITH
This book is an excellent, comprehensive summary in readily available form of modern enzyme kinetics. The book not only contains a complete discussion of enzyme kinetics, including inhibitions, pH effects, integrated equations, and transients, but also discusses many kinetic subjects not usually discussed in reviews of enzyme kinetics. These include, for example, the Powell slide-fit method of analyzing data, the entropy effects in ionic reactions, and an excellent discussion of acid-catalyzed reactions. The weak portion of the book lies in the mechanism discussions. The mechanism of ester hydrolyses on p. 149, which proposes that the imidazole group acts as a base instead of a nucleophile, does not show the thought that went into the sections on kinetics. Many chemists would prefer not to write a concerted cis elimination reaction as is shown on p. 159. There must be also alternatives to the 4-membered ring transition state on p. 167. One is .also not too enthusiastic about mechanisms which require electron conduction by the protein (p. 315). However, mechanism discussions are a minor portion of the book and detract little from the whole. The discussion of energy as a function of reaction coordinate, entropies of activation, and effects of pressure on reactions are excellent. These discussions are quite lucid and are difficult to obtain elsewhere as applied to enzymes. About the last half of the book discusses the kinetics of individual enzymes. Special emphasis is placed on ohymotrypsin, trypsin, ATPase, carboxypeptidase, pepsin, acetylcholinesterase, urease, lactic dehydrogenase, catalase, and peroxidase. Fumarase kinetics are only discussed briefly in respect to the pH effect, and enolase kinetics are entirely missing. The book is designed for the specialist in enzyme kineticis but would be of value to anyone interested in. enzymology. The large amount of kinetic information contained in this book is a bargain at the comparatively modest price. This book should be owned by all enzymologists interested in kinetics. LLOYD L. INGRAHAM, Davis, California
Reviews Advances in Food Research. Vol. 8. Edited by E. M. MRAK and G. F. STEWART. Academic Press, New York, 1958. 437 pp. Price. $12.00. This volume of Advances in Food Research contains reviews of six different subject areas. G. W. Scott Blair’s “Rheology in Food Research” reveals the complexity of “the science of the deformation and flow of matter” as applied specifically to foods. The author refers to his specialty as a “messy science, avoided by the genius, but needful of much research.” The delightfully written last four sections, at least, should be read by food researchers, especially those who deal quite exclusively with palatability factors. “The Blanching Process” by Frank A. Lee will be of assistance not only to food technologists, but also to nutritionists who are interested in retention of nutrients in the food supply, and to biochemists engaged in studies of composition, enzymes, and metabolism of plant tissues. It is interesting that “no single enzyme or combination of enzymes has been conclusively proven to be the cause of the development of off -flavor in unblanched material” because of lack of direct experimental evidence, even though blanching with heat in a food-freezing plant is aimed at destroying enzymes. Few food technologists and food scientists know of the complexity and economic importance of the problem of insect infestation of grain, but “New Methods to Detect and Eliminate Insect-infested Grain” by Max Milner, should stimulate studies of chemical methods, of which there appear to have been relatively few developed to date. The published studies of the inorganic constituents of wines are reviewed thoroughly by Maynard A. Amerine. The quantitative data are overwhelming, but, as the author states, the roles and significance of these components are still largely obscure. The exhaustive review, “Fermentation, Drying, and Storage of Cacao Beans,” by P. A. Roelofsen, leaves one with the belief that many secrets about one of the world’s favorite flavorings are still obscure. Certainly the discoveries of science thus far have had little influence on changing the methods of antiquity for preparing cacao. Biochemist A. C. Hulme has done a masterful job in organizing, integrating, and interpreting the research on “Some Aspects of the Biochem157
OF RIOCHEMISTRY
AND
BIOPHYSICS
86, 157-160 (1960)
Book The Chemical Kinetics of Enzyme Action. By J. LAIDLER, Professor of Chemistry, The University of Ottawa. Oxford University Press, London and New York, 1958. 419 pp. Price $9.60. KEITH
This book is an excellent, comprehensive summary in readily available form of modern enzyme kinetics. The book not only contains a complete discussion of enzyme kinetics, including inhibitions, pH effects, integrated equations, and transients, but also discusses many kinetic subjects not usually discussed in reviews of enzyme kinetics. These include, for example, the Powell slide-fit method of analyzing data, the entropy effects in ionic reactions, and an excellent discussion of acid-catalyzed reactions. The weak portion of the book lies in the mechanism discussions. The mechanism of ester hydrolyses on p. 149, which proposes that the imidazole group acts as a base instead of a nucleophile, does not show the thought that went into the sections on kinetics. Many chemists would prefer not to write a concerted cis elimination reaction as is shown on p. 159. There must be also alternatives to the 4-membered ring transition state on p. 167. One is .also not too enthusiastic about mechanisms which require electron conduction by the protein (p. 315). However, mechanism discussions are a minor portion of the book and detract little from the whole. The discussion of energy as a function of reaction coordinate, entropies of activation, and effects of pressure on reactions are excellent. These discussions are quite lucid and are difficult to obtain elsewhere as applied to enzymes. About the last half of the book discusses the kinetics of individual enzymes. Special emphasis is placed on ohymotrypsin, trypsin, ATPase, carboxypeptidase, pepsin, acetylcholinesterase, urease, lactic dehydrogenase, catalase, and peroxidase. Fumarase kinetics are only discussed briefly in respect to the pH effect, and enolase kinetics are entirely missing. The book is designed for the specialist in enzyme kineticis but would be of value to anyone interested in. enzymology. The large amount of kinetic information contained in this book is a bargain at the comparatively modest price. This book should be owned by all enzymologists interested in kinetics. LLOYD L. INGRAHAM, Davis, California
Reviews Advances in Food Research. Vol. 8. Edited by E. M. MRAK and G. F. STEWART. Academic Press, New York, 1958. 437 pp. Price. $12.00. This volume of Advances in Food Research contains reviews of six different subject areas. G. W. Scott Blair’s “Rheology in Food Research” reveals the complexity of “the science of the deformation and flow of matter” as applied specifically to foods. The author refers to his specialty as a “messy science, avoided by the genius, but needful of much research.” The delightfully written last four sections, at least, should be read by food researchers, especially those who deal quite exclusively with palatability factors. “The Blanching Process” by Frank A. Lee will be of assistance not only to food technologists, but also to nutritionists who are interested in retention of nutrients in the food supply, and to biochemists engaged in studies of composition, enzymes, and metabolism of plant tissues. It is interesting that “no single enzyme or combination of enzymes has been conclusively proven to be the cause of the development of off -flavor in unblanched material” because of lack of direct experimental evidence, even though blanching with heat in a food-freezing plant is aimed at destroying enzymes. Few food technologists and food scientists know of the complexity and economic importance of the problem of insect infestation of grain, but “New Methods to Detect and Eliminate Insect-infested Grain” by Max Milner, should stimulate studies of chemical methods, of which there appear to have been relatively few developed to date. The published studies of the inorganic constituents of wines are reviewed thoroughly by Maynard A. Amerine. The quantitative data are overwhelming, but, as the author states, the roles and significance of these components are still largely obscure. The exhaustive review, “Fermentation, Drying, and Storage of Cacao Beans,” by P. A. Roelofsen, leaves one with the belief that many secrets about one of the world’s favorite flavorings are still obscure. Certainly the discoveries of science thus far have had little influence on changing the methods of antiquity for preparing cacao. Biochemist A. C. Hulme has done a masterful job in organizing, integrating, and interpreting the research on “Some Aspects of the Biochem157