Enzyme kinetics, behavior and analysis of rapid ... - ACS Publications

ranes are the subject of the second chapter. Electron density maps and molecular pa- rameters derived from SCF calculations are emphasized. Molecular ...
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book reviews The introductory chapter consists of a review of the three-center bond concept, a survey of boron hydride, cluster and coordination compound geometries, and a description of the dynamic prwesses sometimes associated with such structures. The most recent theoretical treatments of the handing in boron hydrides and earboranes are the subject of the second chapter. Electron density maps and molecular parameters derived from SCF calculations are emphasized. Molecular orbital shapes and energies for boron hydrides and carboranes are tabulated in the appendices. Chapter three deals with the structural and chemical properties of BzHs, BaHm BsH9, BsHu. BsHm BsHm BgHls, BloHlr, B d m BI6H2o.and Bl8H2~.S p e e d attention is given to "B nmr for its central role in the elucidation of boron hydride structures. A detailed survey of the chemical reactions of these substances is presented. The fourth chapter describes the gas phase studies of monoborane which have provided nearly all the experimental information available on that species. The dissociation of diborane and borane adduets is discussed. The chemical behavior of boranes in solution is the subject of the fifth chapter. Hydroboration, reduction, and hydrogen elimination reactions of borane with organic functional groups are emphasized. Chapter six concerns cationic boron species of the type D2BY2+,D8BYz+,and D4B3+ (D represents a monodentate neutral donor), their svnthesis and chemical ~ r a ~ e r t i e s .

A472 / Journal of Chemical Education

The structures, bonding, and spectroscopic properties of borazines are described in ehaoter seven alone with the svnthetic routes tu these interestmg compounds. The rhemical reactions of horazines are ahu surveyed. Thme boron hydrides and their deriwt~ve ions with cage structures are the subject of chapter eight. Their syntheses and chemical properties are reviewed in thecontext of the special bonding associated with the boron cage frameworks. Chapters nine and ten describe the carboranes, the former chapter treating only the CzBloHlzfamily of crvboranes and the latter concentrating on the several other types of carboranes. Aspects of structure and bonding are introduced, followed by synthetic approaches and chemical behavior. The closing chapters deal with the heteroboranes. First the closo-heteroboranes are described, then the less developed area of the nido-heterobaranes. The burgeoning chemistry of heteroborane anian-metal complexes is reviewed and the known compounds tabulated. This reviewer found only one subject of concern regarding this text: its price. Whatever the reason(s), it is regrettable that this fine text is priced beyond the means of so many workers in the area.

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Russ~IIA. Geanangel Universilyof Houston Houston. Texas 77004

Enzyme Klnetlcs, Behavlor and Analysls 01 Rapid Equilibrium and Steady-State Enzyme Systems Irwin H. Segel, University of California. John Wiley & Sons, New York, 1975. xaii 957 pp. Figs. and tables. 23.5 X 16 em. $27.50.

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The aim of this book is indicated in the preface to be two-fold: to be used as a manual and guide for biological researchers, who analyze steady-state behavior of enzyme systems, and to be used as a textbook about enzvme kinetics. The book is verv valuable for thc first purposr, bur asa rextt,wkcould he remmmrndcd only as a supplementary reading. The subtitle of the book explicitly excludes transient kinetics (mainly stop-flow and relaxation methods) but in a textbook one would expect, a t least in the introductory chapter, some indication of what transient methods could accomplish that steady-state kinetics could not, perhaps with a demonstration of a simple model. This compares unfavorably with the monographs of Gutfreund, Westley, Laidler, and Reiner. Steady-state kinetics could be applied to closedsystems and to open systems with the concentration of the first substrate held constant and the last product removed, a common situation in uioo. This book is limited to kinetics of closed systems, without any mention of multiple steady-states, ascilla-

tions, stability problems, or the crowover theorem. In contrast, J. M. Reiner's textbook has a whole chapter about open systems. The author fails to see the possibilities for the use of computers and numerical analysis in the solution of kinetics problems. Among the many possible applications of numerical analysis to chemical kinetics, which Segel omits to mention is the fact that all of the curves presented in this publication could be directly fitted to experimental data without previous linearization. This could be done by the use of either nan-linear optimization or non-linear least souare method. Thus the I',.. and K,, could he drtrrmmed directly with the help uf rhecamput~r(as they mu* be in non-l~nenrnable\ ' vprsus S dependencies). Different linearized plots are not equally valuable--as the author indicates-there are strong statistical objections against llu - 11s d o t s (discussed bv Wilkinson and more re~ h c s nnd r othrr ommiom could he sum. mari,rd in one m w n c r : the author excluded from hw hrtok anyrhinp, but the exprrs~ions far dependency of initial reaction rates on substrate, activator and inhibitor concentrations, and integrated expressions far simpler schemes. Within this self-imposed limit, the hook contains a more complete list of d o t s and formulas for more reaction srh~mcsthnnothermonographs. It makes it w r y valuahle fur any bahgist who wisher to work in sr~adg.statrenzyme kinetics. Not only are there treatments for enzymes with one, two, and three substrates and a very extensive discussion of all types of inhibition by one inhibitor, hut also treatment far the steady-state kineticsaf twoinhibitors working together, kinetics af enzymes contaminated by endogenous substrates, treatment far activation kinetics, and a chapter about allosteric enzymes. Plots and (in the case of enzymes with two or more substrates) replots are given for each scheme. Besides this, there are very valuable summary plots of conceivahle patterns within the "family" of schemes, such as the plots on pages 249,468, 659,and 900. Within the above mentioned limit, the references are complete and well-chosen. The hook, which was released in May, 1975,contains many references from 1974. However, reference to the Eigen work about diffusion limits for rate constants and references from the Journal of Afothemolz~nlHtocrienrr, are m i i s ~ n g .The trrslmrnt of King-Altman patterns nnd Cleland schemes makes the book valuable as a supplementary reading for kinetics courses. There is one fact which makes this review difficult-there is not one community of enzyme kineticists, but two. The first publishes more in hiologicdy oriented journals and the second in journals of the type of Mathemotical Biosciences, the Journal of Theoretical Biology, Computers in Biomedicine, ete.These two groups do not cross-reference each other often (as could be shown by retrospective reference searches by library computers). The I. Segel book is written exclusively for more biologically oriented readers and does very little to bring more abstract concepts t o the attention of the reader. This review tries t o look a t the hook from both directions. Obviously, the hook looks better (and good) from the viewpoint of practical enzymology than i t does if we regard ~

kinetics. The book costs $27.50 and bas 957 pages. Michael Wagner Nmth~verternUniversity Evansfon. llllnols 60207

An Atlas of Stereochernlslry. Absolute Conflguratlons of Organlc Molecules W. Klyne and J. Buckinghom, Westfield Collzge, London. Oxford University Press, New York, 1974.Figs. and tables. 21.5 X 30 cm. xvi 311 pp. $39.95.

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In recent years it has become apparent, especially in biochemical studies, that no . investigation can he considered complete without a three-dimensional knowledge of the relationship between the molecules concerned, and this cannot be achieved until the absolute configuration of all the compounds is known or s t any rate has been referred t o one arbitrary standard." The latter was the case until 1951 when J. M.Bijovet demonstrated how the technique of anomalous X-ray dispersion could be used to determine directly the absolute configuration of a tartaric acid salt. Since then the method has been used to establish the absolute configuration of numerous comoounds. and therebv olace on a firmer basis the assienments of