Preface ( 1st. Edition).

This book attempts to provide a clear, thorough, and up-to-date treatment of the areas of knowledge fundamental to biochemistry. To this end it presents detailed studies of the physical chemistry of biomacromolecules; of the thermodynamics, kinetics, and mechanisms of enzymatic reactions; of subcellular organization; of the intermediary metabolism of the major classes of chemical substances; and of selected aspects of molecular biology.

The authors have had to use their judgment about the content, organization, and relative depth of coverage that would make the book most useful to the student. Some topics normally discussed in biochemistry texts have been omitted. A specific discussion of carbohydrate chemistry, for instance, is absent because an increasing amount of information on this subject is being presented in basic chemistry courses and excellent discussions can be found in standard textbooks of organic chemistry and biochemistry. Other peripheral topics have been excluded, regretfully, in order to keep the size of the book within reasonable boundaries. We have not been able to deal with such important aspects of physiological chemistry as, for instance, vision, muscle contraction, nerve conduction, and hormonat action. We feel confident, however, that the student who has mastered the fundamentals presented here will be equipped to study these related topics intelligently from other sources.

We feel it desirable to provide the student with an understanding of the chemical and physical properties of biomacromolecules and of the characteristics of the chemical reactions in which they are involved prior to a specific discussion of intermediary metabolism. For this reason the material is organized in the sequence outlined above. Those topics that draw heavily on physical and organic chemistry precede those that are more closely related to the biological disciplines. Treatment of topics in this order also permits the convenient organization of a two- or three-semester course in biochemistry.

Certain concepts introduced early in the book, namely, the physical properties of proteins, enzymatic mechanisms, and the control of enzymatic activity, are discussed at greater length in later chapters. For example, the treatment of enzyme mechanisms in Chapter 7 is rather general and, for the most part, the individual mechanisms are introduced subsequently. Thus, a plausible mechanism for nearly every enzyme encountered in a discussion of carbohydrate metabolism is presented in Chapter 10.

Chapter 10 also includes our first discussion of metabolic sequences and their control. The integration of metabolism and mechanism here has produced a chapter that may appear abnormally long compared with, for example, the chapter concerned with lipid metabolism. It is important to recognize that this disparity in length is largely a result of the integration of topics and does not reflect an unevenness in the depth of coverage of metabolism. On the other hand Chapter 18 appears to be long in proportion to the others because it contains the bulk of our discussion of molecular biology.

This book is intended essentially for seniors or first-year graduate students who have completed the basic courses in organic and physical chemistry but who have had no previous exposure to biochemistry. For students less sophisticated in physical chemistry, certain portions of some of the early chapters will have to be deleted.

On the whole, the text mirrors rather closely the biochemistry courses we have taught at Indiana University over the past few years. In a two-semester course in biochemistry, one would ordinarily cover the material in Chapters 1 through 8 during the first semester and the remainder of the book during the second. For a one-semester course in intermediary metabolism, this book may be used by introducing portions of the chapters on enzymes and coenzymes, followed by Chapter 9 and the subsequent material. Similarly, appropriate selections can be made for an introductory course in Macromolecules of Biological Importance.

One particular problem in writing this book was the question of enzyme nomenclature - whether to use the tried and true trivial names or to adhere rigorously to the new systematic forms proposed by the Commission on Enzymes of the International Union of Biochemistry. After considerable contemplation and with the advice of several of our colleagues, we elected to retain the trivial nomenclature, since it is the one the student would meet with in most of his reading. We could not, for instance, bring ourselves to abandon "aconitase" entirely, in favor of "citrate (isocitrate) hydrolyase", with "aconitate hydratase" as the only trivial alternative allowed. However the systematic nomenclature is introduced and discussed, and systematic names are provided for most of the enzymes encountered.

In presenting the material, the authors have attempted, almost on a page by page basis, to treat each topic with the appropriate depth, steering between the Scylla of superficiality and the Charybdis of unwieldiness. In order to make the book useful as a reference work as well as a text, we have provided substantial collections of data relevant to important topics. Pertinent references to the research literature are made throughout, and a bibliography of books, monographs, and review articles has been placed at the end of each chapter. Here also difficult choices had to be made, and in selecting the articles to be cited, we have tried to choose those that were written most recently or are of particular note, those that summarize a series of related deYelopments, and those that would be available to most students. We extend our sincere apologies to all authors whose important contributions may not have been explicitly recognized in this context.

In closing, we should like to acknowledge the invaluable assistance of many of our colleagues. In particular, we are indebted to Professors R. Baldwin, J. M. Buchanan, R. Clayton, W. W. Cleland, C. Frieden, F. R. N. Gurd, H. O. Halvorson, F. Haurowitz, F. M. Huennekens, W. P. Jencks, E. P. Kennedy, H. L. Kornberg, J. Marmur, A. Meister, W. J. Moore, A. Novikoff, W. Rutter, and A. San Pietro for suggesting major improvements in organization and content and for correcting many errors of fact. If this book has any merit, it is due largely to their contributions. Shortcomings still remaining are, of course, completely the responsibility of the authors.