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Hydrolytic reactions : cobamide and biotin coenzymes PDF

273 Pages·1965·13.302 MB·English
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ELSEVIER PUBLISHING COMPANY an vna 335 J Galenstraat, P.O. Box 211, Amsterdam AMERICAN ELSEVIER PUBLISHING COMPANY, INC. 52, Vanderbilt Avenue, New York, N.Y. iooiy ELSEVIER PUBLISHING COMPANY LIMITED Rippleside Commercial Estate, Barking, Essex Library of Congress Catalog Card Number 62—1035g With yg illustrations and 38 tables ALL RIGHTS RESERVED THIS BOOK OR ANY PART THEREOF MAY NOT BE REPRODUCED IN ANY FORM (INCLUDING PHOTOSTATIC OR MICROFILM FORM) WITHOUT WRITTEN PERMISSION FROM THE PUBLISHERS PRINTED IN THE NETHERLANDS C O M P R E H E N S I VE B I O C H E M I S T RY ADVISORY BOARD SIR RUDOLPH A. PETERS, M.C., M.D., D.Sc, F.R.S. Emeritus Professor of Biochemistry, Oxford ; Department of Biochemistry, Cambridge Chairman CF. CORI, M.D., D.Sc. Professor of Biochemistry, Washington University, School of Medicine, St. Louis, Mo. J.N. DAVIDSON, D.Sc, M.D., F.R.S. Professor of Biochemistry, The University of Glasgow, Scotland E. F. GALE, D.Sc, F.R.S. Professor of Chemical Microbiology, University of Cambridge A. BAIRD HASTINGS, B.Sc, PH.D., D.SC. Director of Biochemistry Division, Scripps Clinic and Research Foundation, La Jolla, Calif. E. LEDERER, PH.D., D.SC. Professor of Biochemistry, Faculty of Science, University of Paris F. LYNEN Max Planck Institute for Cell Chemistry, Munich R. NICOLAYSEN, M.D. Professor of Nutrition Research, University of Oslo S. OCHOA, B.A., M.D., HON.LL.D., HON.D.SC. Professor of Biochemistry, New York University School of Medicine, New York, N.Y. J. ROCHE, D.Sc Professor of General and Comparative Biochemistry, Collège de France, Paris KENNETH V. THIMANN Professor of Biology, Harvard University, Cambridge, Mass. A. W. K. TISELIUS, D.Sc, FOR.F.R.S. Professor of Biochemistry, Institute of Biochemistry, Uppsala, Sweden H. G. K. WESTENBRINK (deceased) Professor of Physiological Chemistry, State University, Utrecht, The Netherlands F. G. YOUNG, M.A., D.Sc, F.R.S. Professor of Biochemistry, University of Cambridge C O M P R E H E N S I VE B I O C H E M I S T RY SECTION I (VOLUMES 1-4) PHYSICO-CHEMICAL AND ORGANIC ASPECTS OF BIOCHEMISTRY SECTION II (VOLUMES 5-11) CHEMISTRY OF BIOLOGICAL COMPOUNDS SECTION III (VOLUMES I2-l6) BIOCHEMICAL REACTION MECHANISMS SECTION IV (VOLUMES I7-2l) METABOLISM 22-2j) SECTION V (VOLUMES CHEMICAL BIOLOGY GENERAL INDEX (VOLUME 28) C O M P R E H E N S I VE B I O C H E M I S T RY EDITED BY M A R C EL F L O R K IN Professor of Biochemistry, University of Liège (Belgium) AND E L M ER H. S T O TZ Professor of Biochemistry, University of Rochester, School of Medicine and Dentistry, Rochester, N.Y. (U.S.A.) V O L U ME 16 HYDROLYTIC REACTIONS; COBAMIDE AND BIOTIN COENZYMES E L S E V I ER P U B L I S H I NG C O M P A NY AMSTERDAM·LONDON·NEW YORK 1965 CONTRIBUTORS TO THIS VOLUME H.A. BARKER, PH.D. Professor of Biochemistry, Department of Biochemistry, University of California, Berkeley, Calif. 95054 (U.S.A.) LEON W. CUNNINGHAM, PH.D. Professor of Biochemistry, Department of Biochemistry, School of Medicine, Station 17, Vanderbilt University, Nashville, Tenn. 37203 (U.S.A.) H. S. JANSZ, PH.D. Laboratory of Physiological Chemistry, University of Leiden (The Netherlands) YOSHITO KAZIRO, M.D., PH.D. Department of Biochemistry, Faculty of Medicine, University of Tokyo, Bunkyo-ku, Tokyo (Japan) ROBERT K. MORTON*, PH.D. Professor of Biochemistry, Department of Agricultural Chemistry, Waite Agricultural Research Institute and Department of Biochemistry, University of Adelaide (Australia) SEVERO OCHOA, M.D. Professor of Biochemistry, Department of Biochemistry, New York University School of Medicine, 550 First Avenue, New York, N.Y. 10016 (U.S.A.) R. A. OOSTERBAAN, PH.D. Medical-Biological Laboratory of the National Defense Research Council—TNO, Rijswijk (Z.H.), (The Netherlands) ALAN PETERKOFSKY, PH.D. Laboratory of Biochemistry, National Institute of Dental Research, National Institutes of Health, Bethesda, Md. 20014 (U.S.A.) HERBERT WEISSBACH, PH.D. Laboratory of Clinical Biochemistry, National Heart Institute, National Institutes of Health, Bethesda, Md. 20014 (U.S.A.) * deceased. GENERAL PREFACE The Editors are keenly aware that the literature of Biochemistry is already very large, in fact so widespread that it is increasingly difficult to assemble the most pertinent material in a given area. Beyond the ordinary textbook the subject matter of the rapidly expanding knowledge of biochemistry is spread among innumerable journals, monographs, and series of reviews. The Editors believe that there is a real place for an advanced treatise in biochemistry which assembles the principal areas of the subject in a single set of books. It would be ideal if an individual or small group of biochemists could produce such an advanced treatise, and within the time to keep reasonably abreast of rapid advances, but this is at least difficult if not impossible. Instead, the Editors with the advice of the Advisory Board, have assembled what they consider the best possible sequence of chapters written by competent authors; they must take the responsibility for inevitable gaps of subject matter and duplication which may result from this procedure. Most evident to the modern biochemist, apart from the body of knowledge of the chemistry and metabolism of biological substances, is the extent to which he must draw from recent concepts of physical and organic chemistry, and in turn project into the vast field of biology. Thus in the organization of Comprehensive Biochemistry, the middle three sections, Chemistry of Biological Compounds, Biochemical Reaction Mechanisms, and Metabolism may be considered classical biochemistry, while the first and last sections provide selected material on the origins and projections of the subject. It is hoped that sub-division of the sections into bound volumes will not only be convenient, but will find favour among students concerned with specialized areas, and will permit easier future revisions of the individual volumes. Toward the latter end particularly, the Editors will welcome all comments in their effort to produce a useful and efficient source of biochem- ical knowledge. Liège/Rochester M. FLORKIN E. H. STOTZ PREFACE TO SECTION III (VOLUMES 12-16) Following Section II of Comprehensive Biochemistry on the Chemistry of Biological Compounds, and preceding sections on Metabolism and Chemical Biology, Section III is devoted primarily to Enzymes. Recognizing the encyclopedic nature of any effort to provide even a minimal treatment of all known enzymes, the Editors have chosen instead to select examples from modern enzymology in which advances in reaction mechanisms have been made. Certainly a well-established biochemical reaction mechanism is the carrier function of coenzymes which serve as the prosthetic groups of enzymes, and Section III has a primary purpose of providing treatment of both the chemistry and function of the coenzymes. Other chapters, however, treat thermodynamic and kinetic aspects of enzyme catalysis, hydrolytic enzymes displaying "active center" characteristics, and chelation and stereochemical considerations in enzyme catalysis. A considerable portion of the Section deals with biological oxidation mechanisms. Finally, Section III would seem incomplete without inclusion of the recommendations of the Enzyme Commission of the International Union of Biochemistry and the classified list of Enzymes. Liège/Rochester M. FLORKIN Ε. H. STOTZ Chapter I Cholinesterases, Esterases and Lipases R. A. OOSTERBAAN Medical-Biological Laboratory of the National Defense Research Council— TNO, Rijswijk (Z.H.), (The Netherlands) AND H. S. JANSZ Laboratory of Physiological Chemistry University } of Leiden (The Netherlands) 1. Introduction The enzymes which will be discussed in this Chapter have in common that they catalyze the hydrolysis of carboxyl esters. In recent years evidence has accumulated indicating that enzymatic carboxyl ester cleavage is, in many cases, governed by a mechanism which is basically similar for different enzymes. The evidence has been derived from studies on the kinetics of the interaction of these enzymes with substrates and inhibitors and specifically from chemical analysis of the active site. The similarity in mechanism may be due to the presence of a common or at least related active site in different carboxyl esterases. In Une with the general objective of this series of papers on biochemical reaction mechanisms an attempt is made to present infor- mation on enzymes, their substrates and inhibitors which contributes to an understanding of the molecular basis of the general mechanism of enzymatic ester hydrolysis. Also included are data which are relevant to an under- standing of the molecular basis of substrate specificities of individual enzymes. Evidently, a discussion on a molecular basis must be limited to those enzymes that have been purified and characterized in detail. Conse- quently, the discussion will be confined to the few representatives within the groups of cholinesterases, lipases and esterases that have been extensively References p. 47 [I] 2 CHOLINESTERASES, ESTERASES, LIPASES I purified and characterized. For a detailed account of the occurrence and properties of the many other carboxyl esterases and for alternative aspects outside the scope of the present paper, the reader is referred to reviews 1-3 available in the literature . 2. Classification of carboxyl esterases Many enzymes that hydrolyze carboxyl esters exhibit a very broad substrate specificity. Consequently, a classification based on their substrate specificity will be of limited value. However, the carboxyl esterases may be designated as A-, B- or C-esterases on the basis of their reaction with organophosphates (e.g. DFP). Esterases of the A-type are not inhibited by organophosphates ^OCH(CH ) 32 F—p==o OCH(CH) 32 (1) Diisopropyl phosphorofluoridate (DFP) but they hydrolyze these compounds. B-esterases are sensitive to inhibition by organophosphates in low concentrations. The C-esterases do not hydrolyze the organophosphates nor are they inhibited by these compounds. Different 4 5 A- and B-types of carboxyl esterases have been found in plasma » . The 67 C-type of carboxyl esterase occurs in hog kidney ' . The separation of an A-type carboxyl esterase (Α') from two B-type esterases (B' and B") by zone electrophoresis of horse plasma is shown in Fig. i. The A' enzyme rapidly hydrolyzes phenyl acetate and is not inhibited by organophosphates. Aliphatic carboxyl esters are poor substrates for this enzyme. The B'- and Β "-esterases are both inhibited by organophosphates in low concentrations. In contrast to the Β'-esterase, the Β "-esterase is inhibited by physostigmine (eserine) in low concentrations. The sensitivity to inhibition by physostigmine may be used as a further method for distin- guishing different types of B-esterases. The physostigmine-sensitive enzymes hydrolyze choline esters (but also aromatic esters) ; they are usually des- ignated as cholinesterases. The Β'-esterase hydrolyzes aliphatic as well as aromatic carboxyl esters. Low physostigmine-sensitive esterases of this type attacking short-chain fatty acid esters are usually named ali-esterases. The term lipase is used for enzymes that hydrolyze long-chain fatty acid esters, e.g. fats. The lipases, however, also hydrolyze short-chain fatty acid esters. 8 It has been suggested by Desnuelle and others to use the term lipase for enzymes which act on undissolved substrates. The term ali-esterase would refer to enzymes acting on substrates in solution. This distinction becomes 2 CLASSIFICATION OF CARBOXYL ESTERASES 3 Fraction number Fig. ι. Distribution of esterase activity and total' protein (—· — ·—) of horse plasma after column electrophoresis. Esterase activities against phenyl acetate ( • · · · •), 5 phenyl butyrate ( • •) and butyrylcholine (—ο—Ο—). (From Augustinsson ). vague however, since the carboxyl esterase from wheat germ hydrolyzes both undissolved and dissolved substrates. The differences in mechanism of action between Α-, B- and C-types of esterases may well be of a qualitative rather than of a quantitative character. It is known that the inhibition of B-type esterases by organophosphates in- volves a phosphorylation of the active centre of these enzymes. The rate of inhibition, however, is greatly different for individual esterases of the B- 5 type. Butyrylcholinesterase reacts 5 · io times faster with tetra-ethyl pyro- phosphate than does trypsin. The difference between a B- and C-type esterase may then be that the latter reacts with organophosphates at an extremely slow rate. Likewise, the rate of dephosphorylation may differ considerably for different types of B-esterases inhibited by organophos- 9 phates . An A-type esterase may hydrolyze organophosphates because it is rapidly phosphorylated by organophosphates like some B-esterases but unlike the latter, the phosphorylated Α-esterase is rapidly dephosphorylated. In this 10 way Van Asperen and Oppenoorth explained the observed development of resistance of house flies against organophosphates. The resistance was presumed to be due to a single gene mutation which causes the synthesis of an A-type of esterase instead of the usual B-type which is present in the wild type. It should be noted that another group of enzymes from tissues (DFPase, References p. 47

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