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Book Review The Biochemistry of Folic Acid and Related Pteridines. Vol. 13 in the series УFrontiers of BiologyФ. By R. L. Blakley

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problems, which are important to electrochemists in general.
The special applications to fuel cells are certainly kept in the
foreground, but only as a continuous theme that allows these
general facts to be illustrated for a particular example.
The Use of Chemical Literature. Published by R. T. Botrle.
In the series “Information Sources for Research and
Development”. Butterworth, London 1969. 2nd Edit., xii
+ 294 pp., numerous illustrations and tables, bound 65 s.
A brief introduction (Chapter 1) is followed by a historical
survey, beginning in 1839 (Grove) and ending in 1933 (Buur
and Tobler). This chapter is thus “historical”, but not in the
sense that we can nowadays pass over it with a tolerant smile.
I t is in fact here that we see clearly that though refined
methods of investigation and advanced technology have led
in the meantime to important progress, the fundamental
problems have hardly changed, and in particular, the idea
postulated by Baur is still surprisingly current.
The present book is the first in the series “Information
Sources for Research and Development” published by D. J.
Foskett and R . T. Bottle. Since important changes have taken
place in the field of information since the appearance of the
first edition (1962) [*I the authors have revised and expanded
almost every chapter. Thus, sections have been added on
spectroscopic data, physical methods, literature on analytical
chemistry, and sources relating to prices and manufacturers
of chemicals. The original chapters on data collections,
physicochemical literature, literature on inorganic chemistry,
nuclear chemistry, organic chemistry with a special chapter
on Beilstein, and patents have been supplemented by a chapter on polymer chemistry. New also is the chapter on less
conventional sources of information like market reports,
personalities (Who’s Who?) etc.
The next few chapters (3-9) present what was described
above as a textbook. The thermodynamics and the kinetics
of electrode reactions are dealt with in detail; the concept of
irreversibility, the types of overpotential, electrocatalysis, and
the shape of the current-voltage curve are discussed. The
authors attach special importance to the study of transport
processes, which are often regarded as being of minor
significance, and consequently go into great detail in this
chapter (79 pages). The next sections lead us more toward the
practice of fuel cells; these are the chapters on the electrode
structure, experimental methods, and the oxygen and hydrogen electrodes.
This first, general part of the book has already presented all
the theoretical and practical information about “normal”
fuel cells (Hz/Oz in aqueous electrolytes) that is worth
knowing, so that only special types remain to be discussed
separately in the succeeding chapters ( 1 k 1 3 ) . These are
systems that use liquid fuels, those that utilize hydrogen
indirectly, i . e. after conversion of hydrocarbons, those that
burn hydrocarbons directly, and those in which non-aqueous
electrolytes, i.e. molten salts or solid electrolytes, are used.
The discussion of ion exchangers as electrolytes (Chapter 14)
leads over t o the description of complete fuel batteries
(Chapters 14 and 15). The authors confine themselves here to
two types that have already proved themselves in practice,
i.e. the batteries developed by General Electric for the
Gemini space missions and the methanol batteries constructed by Brown-Boveri for the long-term supply of power
to television translators. This limitation is justified o n the
grounds of the enormous amount of data, which cannot be
covered in a single book. On the other hand, because of this
very abundance of material, the reader would expect such a
comprehensive work to contain a critical selection of fundamentally or technically interesting prototypes, even if these
have not yet come into practical use, even at the risk of being
proved wrong in the assessment of future prospects. Instead
of this the last chapter, which deals with the decisive step
from the fuel cell t o the fuel battery, closes with a consideration of the main problems involved, though further
information can be obtained from references. The surprising
brevity of the discussion of the technique of battery construction is compensated for, however, by a more thorough
account of the development and practical testing of the Gemini batteries, interesting details of which can be provided
by the authors as former employees of General Electric.
The book on the whole is thorough, comprehensive, and
flowingly written in the “dry” theoretical sections. Its main
value probably lies in the fact that it is a valuable source of
information for the expert, but is equally suitable for use by
the non-expert as a n understandable introduction to what is
for him a new field. Despite the continuous theme, each
chapter, and particularly those that are predominantly
theoretical, is self-contained (some of them have already
been published as independent articles), so that special
sections may be skipped for a general picture. This is particularly worthy of mention in that in this age of space travel,
which has provided the most spectacular demonstration so
far of the value of fuel cells, even many who are not electrochemists may be expected to have a n interest in these modern
sources of current.
Helmut Schmidt
[NB 877 IE]
Although the work is designed predominantly for scientists
from the English-speaking world, as the publisher emphasizes
at the beginning, and the directions for the use of the chemical
literature were written from this standpoint, the book should
be generally useful to all readers interested in this field. The
chapters o n the work of libraries, primary literature (journals,
reports, dissertations), secondary literature, in which the
well-known larger abstracting services are described in detail,
and works of reference give a particularly good survey even
though the German-language services, which of course are
important for the German scientist, are given only incomplete coverage.
A special chapter is devoted to translations and translation
journals. A reference section for Russian literature is also
supplied. The list of acronyms used in the literature and their
meanings (Appendix I) is extremely useful. Appendix 11
contains exercises (with answers) on problems broached in
the book.
I t is difficult to see why Dissertation Abstracts and information services are mentioned under primary sources, while
there is no reference to patents in this section. Furthermore,
the Signal Information from the All-Union Institute for
Scientific and Technical Information, Moscow, is not included in the section o n information services while the reference to Express Information is inappropriate at this point.
The index at the end of the book is valuable, like every aid t o
search, but unfortunately random checks showed that it is
not complete (no entry under CA Condensates and Basic
Journal Abstracts and no reference to the paragraph on
ASLIB on p. 18).
Despite its minor shortcomings, however, this book can be
recommended to those interested in the field of information.
Christian Weiske [NB 887 IE]
The Biochemistry of Folk Acid and Related Pteridines. Vol. 13
in the series “Frontiers of Biology”. By R. L . Blukley.
North Holland Publ. Co., Amsterdam-London 1969. 1st
ed., xxi, 569 pp., Dfl. 90.-.
The chemist knows the pterins only as a n unusual class of
rather intractable heterocyclic natural pigments that lead a
somewhat aloof existence in the wings of the brimstone
butterfly or in the skin of frogs. The biochemist also knows
that pteridines and pteridine derivatives occupy key positions
in metabolism as cofactors of several reactions. They have
recently attracted increasing attention from plant physiologists as primary photoelectron acceptors in green leaves,
from which the best-known conjugated pteridine derivative,
folic acid, takes its name. However, relatively simple unconjugated pterins are active here and in the hydroxylation
of aromatic rings; the more complex folic acid, o n the other
[*I See Angew. Chem.
75, 740 (1963).
Angew. Chem. internat. Edit.
Vol. 9 (1970) No. 9
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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