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Book Review Elektrolytgleichgewichte und Elektrochemie (Electrolyte Equilibria and Electrochemistry). Fachstudium Chemie Arbeitsbuch 5. By E.-G. Jger K. Schne and G

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The role of cerebroside sulfate as opiate receptor is discussed
in an article by H . H . Loh, P. I: Law, 7: Oswald, 7: M .
Cho, and E. L. Way. Cerebroside sulfate possesses most of
the properties required of an opiate receptor, namely high
affinity and the ability to bind stereoselectively. Although
these findings still do not allow proof of identity, it is most
likely that some interrelationship exists. Cerebroside sulfate is
a component of brain tissue, and a partially purified opiate
receptor from mouse brain proved to be chemically the same as
cerebroside sulfate. Further investigations showed that
reduction in the availability of cerebroside sulfate was accompanied by a decrease in analgesic action of morphine and the
number of binding sites. [Possible Involvement of Cerebroside
Sulfate in Opiate Receptor Binding. Fed. Proc. 37, 147-152
(1978); 36 references]
[Rd 25 IE]
In cyclophosphazene clathrates the guest molecules are located
in a tunnel, the dimensions of which are dependent upon the
substituents of the host molecule. H . R. Allcock surveys
this field. The parent molecule ( I ) , which was discovered
by chance to act as a host molecule, forms planar aggregates
of three molecules at a time. The next layer is twisted in
such a way that a tunnel of 4.5-5A diameter is formed
which can accept, e.g., benzene. (1) is suitable for separating
mixtures of, say, heptane and cyclohexane as well as m-xylene,
p-xylene, and ethylbenzene. The analog of ( 1 ) obtained from
2,3-naphthalenediol also forms clathrates; the tunnel has a
diameter of 9-10A. As shown for compound (2) which
does not form clathrates, it is the shape of the molecules
of this series which is responsible for their properties. [Cyclophosphazene Clathrates-Exploring the Adjustable Tunnel.
Acc. Chem. Res. 1 1 , 81-87 (1978); 33 references]
[Rd 21 IE]
The identification and regulation of a- and P-adrenergic receptors form the subject of a review by R. J . Lefkowitz. Methods
for the direct binding of radioactive ligands to a- and padrenergic receptors have been developed in the course of
the last few years. Radioactively labeled adrenergic antagonists
or agonists are used in order to identify receptors in the
membrane fractions of catecholamine-sensitive tissues. In the
case of p-adrenergic receptors the close relationship between
binding and activation of adenylate cyclase simplifies identification. Such direct receptor-binding investigations provide
further useful information about the molecular and regulatory
properties of receptors. [Identification and Regulation of
Alpha- and Beta-Adrenergic Receptors. Fed. Proc. 38, 123129 (1978); 87 references]
[Rd 23 IE]
Affinity-labelingof estrogen receptors is the subject of a report
by J . A . Katzenellenbogen. As shown by competition experiments, estradiol and hexestrol derivatives bearing photoreactive diazocarbonyl or azide groups exhibit receptor-binding
activity, and, after irradiation, inactivate the receptor. In
unpurified uterus specimens other proteins besides the receptor
are labeled. From previously purified specimens a photolabeled product can be isolated which shows all the properties
of an estrogen receptor. [Photoaffinity Labeling of Estrogen
Receptors. Fed. Proc. 37, 174-1 78 (1978); 28 references]
[Rd 24 IE]
Elektrolytgleichgewichteund Elektrochemie (Electrolyte Equilibria and Electrochemistry). Fachstudium Chemie, Arbeitsbuch 5. By E.-G. Jager, K . Schone and G . Werner. Verlag
Chemie GmbH, Weinheim-New York, 1977,lst edit., 308
pp., 64 figs., numerous tables, paper, D M 34.00.
The present volume is part of a comprehensive work intended
to provide chemistry students with the necessary fundamentals.
Textbooks and workbooks serve as an aid to self-study,
tutorials, and practicals.
The introductory text contains a number of basic questions
following a short presentation of the problem. The aim is to
check whether the student has understood the corresponding
section in the textbook. This section is followed by instructions
for practical experiments and calculation exercises, the solutions to which are given at the end of the book.
The present volume deals mainly with electro-analytical
applications of electrochemical equilibria. Problems of kinetics
are only briefly touched upon in the introductory chapter on
the fundamentals, where the authors discuss the conductivity
of electrolyte solutions, reversible cell potentials, and polarization when a current is flowing, together with experimental
methods. The other chapters consider various equilibria
(redox, acid-base, complex, precipitation, extraction, and ionexchange), methods for the determination of equilibrium constants,and the corresponding analytical methods, such as redox
titrations, complexometry, and gravimetry.
The book conveys sound basic knowledge. In a few cases
the terminology is not quite appropriate: e.g. “depolarizer”, or
“resistance capacity” of a conductivity cell (instead of*cell
constant). Some definitions could be improved (e.g.,not every
Angew. Chem. I n t . Ed. Engl. 17 (1978) N o . 7
cell through which no current flows is in equilibrium). In
another place, the wrong impression is given that corrosion
depends only on local cell action. It is particularly regrettable
in a modern textbook that the IUPAC recommendations for
definitions and nomenclature are often ignored. Apart from
such minor shortcomings, however, this book should prove
a valuable study aid that will find many friends, not least
because it is reasonably priced and well presented.
K . E. Heusler [NB 431 IE]
Biophysik-ein Lehrbuch (Biophysics-A Textbook). Edited
by W Hoppe, W Lohmann, H . Markl, and H . Ziegler. Springer-Verlag, Berlin-Heidelberg-New
York 1977. 780 pp.,
640 figs., bound, DM 98.-.
The title of this book, which contains contributions by
fifty-two experts, inevitably poses the question: “What
is biophysics?’ Since animate and inanimate nature obey
the same laws, biophysics cannot be understood as a science
sui generis. However, living processes can be treated physically,
just as there are genetic and chemical ways of consideration,
and it is as such that biophysics surely wants to be known.
Each of these modes of treatment has given birth to its own
tools and techniques. Since more and more physicists are
turning to biology, and physical methods are used increasingly
to understand life processes, there is bound to be an interest
in a textbook explaining the mode of thinking and the physical
laws and techniques that have decisively contributed to the
solution of biological problems and have introduced an
eminently fruitful development, though admittedly this is credited to molecular biology rather than to biophysics. The
present attempt at writing a textbook on biophysics has unfortunately been unsuccessful, because the basic biological concept is missing. There is no guiding principle that could
tie together the many jewels that occur in this
book in a clear and logical manner. Without such a thread
of Ariadne the reader soon gets lost in a maze of problems
that appear to lead an isolated life of their own. The editors
must be given the credit of anticipating these difficulties and
trying to overcome them. They therefore decided to incorporate “supplementary scientific material” taken from biology
in concentrated form, though this was bound to remain a
patching-up operation. The core of the book should have
been made up of topical problems in biology, and some of
these are indeed dealt with. Physics and physical chemistry
should then have provided the requisites for describing these
topical biological problems in physical and physicochemical
terms, for analyzing them, and for making them comprehensible. Only thus would an unfortunate intermixing of
physics, chemistry, and biology have been avoided.
The book begins by describing the cell, nucleic acids, and
proteins. Walter Hoppe, Brunner and Dransfeld et al. then
describe physical methods, namely X-ray and electron diffraction and light scattering in detail and searchingly-in fact
uniquely in this form. It was these methods that elucidated
the structure of biological molecules and made possible a
study of biology on the molecular level. However, one misses
the cornerstones of molecular biology, which are only offered
later in Chapters 9 and 10 by Huber and Zillig as “supplementary scientific material”. A possible criticism is the emphasis
given to the discussion of various physical methods for the
investigation of biological molecules (Chapter 3). For example,
IR and more especially Mossbauer spectroscopy are described
in greater detail by Kaluius and Parak than the methods of
Angew. Chem. Int. Ed. Engl. 17 ( 1 9 7 8 ) N o . 7
nuclear magnetic and electron spin resonance. I doubt whether
the student will really understand how important these methods
were for the elucidation of membrane structure or enzyme
catalysis, for example, when reading about resonance spectroscopy. The fundamental Chapter 4 on intramolecular and intermolecular interactions (Hofacker, Ladik) reinforces my view
that physical and physiochemical aspects are best described by
physicists, physical chemists, and theoretical chemists, who
would hardly describe themselves as biophysicists. A competent
treatment suffices for the demands of the chemists and physicists just a much as it teaches the molecular biologists. I am
here including the contributions by Hans Kuhn and Friedrich
Dorr about energy-transfer mechanisms (Chapter 5) and thermodynamics (Chapter 8). These contributions, including the
already discussed Chapters 3 and 4, could have been made
into an excellent textbook of physics and physical methods
for biologists and biochemists. For the reader interested in
membrane structure and function Chapter 11 is a source
of valuable but not easily digested information. Certain carefully selected examples from Chapter 12 (receptor transduction) and Chapter 13 (photophysics, photochemistry, and
bioenergetics) might have merited consideration, but such
a degree of heterogeneity is hardly justified. Bioenergetics
could have been a central theme, but then the physical principles would have had to be coordinated better with the
biological and biochemical phenomena. Photobiology could
have been followed by a selective treatment of physical
influences on life processes (cf. Chapters 15 and 16), because
what hides under the term “biomechanics” (Chapter 14, pages
503-600) are system physiology and engineering applied especially to biological locomotion. Like routine methods (use
of isotopes) and special fields such as radiation physics
(Chapter 6 ) this should have been left to relevant handbooks.
The up-to-date and readable treatment of the molecular biology of muscle contraction by Mannherz and Holmes is amiss
in this chapter; it ought to have been coordinated with Huber’s
contribution to reinforce the relationship to molecular biology.
The last two chapters, on Cybernetics (Chapter 17 by Marko,
Creutzfeldt and Reichardt) and Evolution (Chapter 18), are
undoubtedly part of the central theme of present-day biology.
They open up fascinating insights into complex biological
systems (for example the flight orientation of flies by Reichardt)
and the evolution of biological systems (Hans Kuhn). (The
Eigen theory ofevolution is presented by a well-known, already
published, popular introduction by Peter Schuster.) There was
a splendid opportunity here of awakening an understanding
of where the boundaries of physical knowledge about nature
lie if these contributions had been put at the center of the
physical considerations and analysis together with ones about
structure and function of biopolymers (proteins and nucleic
acids) and membranes as main biological reference points.
The whole would then have become better than its parts and
not the parts better than the book as a whole.
The editors have made little effort to critically edit and
coordinate the individual contributions, and they emphasize
this themselves in the preface. Unfortunately, they cannot
be praised for this laissez faire attitude. The biologist is going
to find it difficult to recognize the relationships to physics,
currently so topical, and the physicist and the chemist are
going to miss the biological relationships which help them
to understand the laws of the make-up and function of living
systems, the “logique du vivant” as FranGois Jacob puts it.
What remains is a mixture of essays about physics, chemistry,
and biology, some of which are so good that despite all
reservations they can be recommended with good conscience.
Sadly, the textbook as such cannot be recommended.
Ernst J . M . Helmreich [NB 420 aE]
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