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Book Review The Structure and Action of Proteins. By R. E. Dickerson and I. Geis

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hand, must be reduced to the tetrahydrogenated cofactor
before it acquires its coenzyme functions in the metabolism
of the active C1 units, their transfer, and their interconversion. This enables them to act in the degradation of histidine
and serine, in the synthesis of purines and nucleic acids, in
the biosynthesis of methionine, in the formation of methane,
and finally as an induction cofactor for protein synthesis in
bacteria and cell organelles. Vitamin B12 derivatives also
take part in some reactions of the C1 compounds, and this
leads to a system of vitamin interrelations that has not yet
been fully elucidated. The pteridines are biosynthesized from
the purines (the cell synthesis of which is itself folate-dependent); the biosynthesis of the folate cofactors also requires p-aminobenzoic acid, and can be blocked by sulfonamides, as well as by folate antagonists that inhibit the folk
acid reductases. This offers various possibilities of chemotherapeutic interventions in the metabolism, which have
become very widely used, as is well known.
All these confusing facts are presented carefully and faultlessly by R. L. Blakley, a pioneer of several fields of the
chemistry and biochemistry of folic acid coenzymes, in this
fine volume. The subject matter ranges from the nomenclature of conjugated and unconjugated pteridines, their
occurrence in nature, and their chemistry and biochemistry
to the enzymatic reactions catalyzed by them and carried out
with them (in some cases in conjunction with the corrin
cofactors) for absorption, storage, and analysis. The extensive originalliterature up to 1967 has been almost completely
sorted, ordered, and critically evaluated. This skill in the
assessment of the arguments is seen in the analysis of the
data and observations reported by various groups of workers,
which are discussed fairly and never without a careful and
reasonable judgement based on experience with the difficult
material and the experimental traps that result from premature interpretations. This is an excellent book in every
respect, in which the answers to all relevant questions can be
found. The factual information and the comparison of
hypotheses will provide the reader with welcome stimuli as
well as warnings. The presentation of the book is also extremely good, free from errors, and an aesthetic pleasure,
particularly in the clear formulas.
[NB 885 IEJ
L. Juenicke
The Structure and Action of Proteins. By R. E. Dickerson and
Z. Geis. Harper and Row, Publishers, New York-EvanstonLondon 1969. 1st Edit., viii + 120 pp., numerous figures,
paperback, DM 20.50.
In conjunction with the determination of amino-acid sequences, X-ray structural analysis of crystallized proteins has
opened up completely new horizons for the understanding of
enzymes. The importance of this development has not so far
been adequately reflected in introductory biochemistry textbooks. One does of course find the obligatory illustration of
the hemoglobin molecule, but the accompanying text is invariably so meager as to contribute very little to one's understanding of protein structure; at best it can merely highlight
the current importance of this field.
In the circumstances it is gratifying to report that the beginner
will find X-ray enzymology very clearly explained in the
present book by Dickerson, of the California Institute of
Technology, who has himself taken part in a number of X-ray
structural investigations. Starting with amino acids, a description is given of the rules according to which a peptide
chain can fold itself to the secondary structure, and of the
stability conditions (using the Ramachandran diagram). This
is followed by a lucid and detailed, though not overelaborate
discussion of the form of structural proteins (silk fibers,
a-keratin, collagen), molecular carrier proteins, (myoglobin,
hemoglobin, cytochrome c), and enzymes (lysozyme, ribonuclease, chymotrypsin, papaine, carboxypeptidase).
The book ends with a chapter on electron-microscope studies
of proteins, which are built up from a number of subunits.
Angew. Chem. internat. Edit. 1 VoI. 9 (1970) NO. 9
Just to whet the appetite, the author refers briefly, when
considering future prospects, to the complement system from
the standpoint of the enzymologist. Nowhere will the reader
find himself bogged down in purely descriptive, morphological treatment, every effort being made to bridge the gap
between structure and function. Proteins are regarded as
machines on the molecular scale, with the atoms as moving
parts. A decisive contribution to didactic clarity has been
made by Zrving Geis, who has already gained world-wide
acclaim for his brilliantly executed illustrations in the
Scientific American. Both text and the illustrations in this
introductory textbook are exemplary. A supplement containing 55 stereo illustrations of nine of the proteins discussed
in the book and accompanied by a simple viewer constitute
another useful feature. The book may be warmly recommended to everyone interested in the development of modern biochemistry.
Guido Hurtmann
[NB 892 IE]
Methoden der organischen Chemie (Houben-Weyl). Bd. VII,
Teil 4: Sauerstoffverbindungen I1 (Methods of Organic
Chemistry (Houben-Weyl). Vol. VII, Part 4: Oxygen Compounds 11). Edited by Eugen Muller. Georg Thieme Verlag,
Stuttgart 1968. 4th Edit., ix, 508 pp., numerous formulas,
bound DM 178.-.
The present volume describes the preparation and transformation of isatins, thionaphthenequinones, ketenes, carbon
suboxide, and ketene derivatives.
The first two chapters, on isatins and thionaphthenequinones
(including 3-hydroxythionaphthenes)(pp. 1-51) provide the
dye chemists with a detailed survey of historically interesting
and now apparently closed field of indigoid dyes.
Most of the volume (pp. 5 3 4 4 7 ) deals with the diversified
field of ketenes and ketene derivatives, which is of great importance to the preparative organic chemist. In addition to
the preparation methods which are already regarded as"c1assical", such as the pyrolysis of ketones and carboxylic acid
derivatives, the modern photochemical methods (pp. 73-75)
and the photofragmentation method (p. 106) for the preparation of ketenes are also described.
Considerable space @p. 113-225) is devoted to the many
applications of the extremely reactive ketenes. In addition to
their use as acylating agents for compounds which contain
active hydrogen, the addition reactions, which frequently
proceed with cyclization (e.g. formation of p-lactams and
dihydropyridines, 1,4-cycloadditions, additions of ketenes to
enamines, vinyl ethers, and isocyanates), and which have led
to a wide range of novel heterocyclic compounds, are also
discussed. Reactions with carbonyl compounds, which lead
to different products depending on the reaction (e.g. to p- or
y-lactones), are then dealt with. Separate chapters are finally
devoted to reactions with halogens, inorganic acid halides,
and organometallic and nonmetallic organoelement compounds.
The next section (pp. 226-285) deals with the preparation and
transformation of diketenes and of oligomers and polymers
of ketenes. One of the most important properties of diketene
is its ability to act as an acetoacetylating agent (3-oxobutanoylating agent) for hydroxy and amino compounds. In suitable cases these compounds react further to give heterocyclic
compounds, in the same way as acetoacetic ester. A subsection deals with the use of diketene for C-acetoacetylation
in the presence of Lewis acids. The preparation and reactivity
of alkylketene dimers, ketoketene dimers, ketene oligomers,
and ketene polymers are then discussed. As in the other
chapters, the material is presented clearly here with the aid
of numerous tables.
Carbon suboxide is described in monograph (pp. 286-311)
form. The preparative chemist is stillvery interested in this
fourfold heterocumulene. It is therefore particularly pleasing
to find that its many reactions have now been described in
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