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Book Review Metallothioneins. Synthesis Structure and Properties of Metallothioneins Phytochelatins and MetalЦThiolate Complexes. Edited by M. J. Stillman C. F. Shaw III and K. T

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Chapter 2 (225 pp.) is concerned with “Materials: Preparation, Structures and Properties”. Here the reader is introduced to many different types of materials, and the temperature-dependent conducting properties of several wellknown families of proton conductors such as Nafion and
p”-alumina are described. In the contribution by Dickens
and Chippendale we get to grips with the problems of the
nonstoichiometric oxides of the transition metals W, Mo, V,
Cr, and U. The analysis of the constitution of these materials
has only been possible through a combination of methods,
some of which are fairly unusual in chemistry: vibrational
spectroscopy, magic-angle-spinning (MAS) N M R spectroscopy, and incoherent inelastic neutron scattering. To develop quantitative relationships that describe how the hydrogen in these compounds influences the constitution and
properties calls for lateral thinking and an imaginative approach to analytical results, analogous to dealing with
macromolecular materials in biochemistry, for example.
Next some specific groups of proton conductors are discussed: perovskites, hydroxides of the alkaline earth metals,
the oxyacids of phosphorus, arsenic, sulfur, selenium, and
chlorine, and graphite intercalation compounds. However, i t
is not obvious why it was thought necessary to treat the next
three groups of materials, the p- and f3”-polyaluminates, the
zeolites, and the Nasicon phases, in a separate sub-chapter
entitled “Inorganic Ion Exchangers”. The same also applies
to the following sub-chapter on “Layer Hydrates”; this includes some very special groups of proton conductors (e.g.,
y-Zr(HPO,),), which are not hydrates at all but hydroxo salts
or hydrogen phosphates of the tetravalent metals Ti, Zr, and
Ce, and, moreover, d o not necessarily have layer structures.
Chapter 3 (115 pages) is entitled “Proton Dynamics and
Charge Transport”. and deals with the special methods used
for characterizing proton conductors. The eight articles
describe the use of vibrational spectroscopy, N M R spectroscopy, various methods for measuring dielectric constants, impedance spectroscopy, and neutron scattering.
Emphasis is placed on the discussion of typical results for
some specific materials, thereby providing readers who intend to use these methods with the theoretical background
needed to interpret spectra or other data.
Chapter 4, “Proton Diffusion Mechanisms”, consists of
three short articles by Slade, Colomban, Novak, and Kreuer
which discuss specific proton conduction mechanisms. These
discussions link up with some fundamental aspects of bonding and thermodynamics in proton conductors (e.g., the dynamics of the proton in hydrogen bonding, as treated in
Chapter 1). However, it is difficuIt to see why the fundamental article by I. A. Ryzhkin on ‘‘Ice’’ was not included here
instead of in Chapter 2.
In Chapter 5, “Devices”, we learn something about the
latest state of the art in applications to secondary energy
storage and to primary energy generation using fuel cells.
Also in the fields of gas sensors, electrochromic devices, field
effect transistors, and super-capacitors there are articles reporting on recent developments, results with pilot systems,
and prospects for new types of thin film elements.
The editor, P. Colomban, has made a good choice of topics and authors. In putting together the specialized contributions of 38 authors in five main chapters with altogether 575
pages he has, remarkably, managed to avoid over-stretching
the material or losing the reader’s attention by offering too
heterogeneous a presentation. Chemists, physicists, and engineers will all find the book informative. The detailed introduction, comprehensive subject index, and table of symbols
all afford clear and easy access to the material. References
are given throughout to original papers as well as reviews, a
mark of quality in a specialist book such as this with an
international team of authors.
Jiirgen Feisclze
Fakultiit fur Chemie
der Universitlt Konstanz (FRG)
Metallothioneins. Synthesis, Structure and Properties of
Metallothioneins, Phytochelatins and Metal-Thiolate
Complexes. Edited by M . J. Stillman, C. L: Shaw III, and
K. 1: Suzuki. VCH Verlagsgesellschaft, Weinheim/VCH
Publishers, New York, 1992. IX, 443 pp., hardcover
D M 218.00.-ISBN 3-527-2801 1-110-89573-785-X
Seven years after the publication of the two-volume work
“Metalloproteins”, edited by P. Harrison, the same publishing house has now brought out a volume devoted expressly
to metallothioneins. The editors’ aim is to present a collection of review articles by recognized experts so as to cover the
rapid developments that have occurred in this field. The
book consists of 16 chapters. After a succinct introduction in
Chapter I to the metallothioneins and related polypeptides
(cadystins and phytochelatins), the following topics are
treated: preparation, isolation, and identification (Ch. 2).
X-ray structure determination (Ch. 3), studies using circular
dichroism (CD), magnetic circular dichroism (MCD), and
emission spectroscopy (Chs. 4 and 5), kinetic studies of cluster formation, metal exchange reactions, and ligand substitution (Ch. 7), phytochelatins and cadystins: synthesis and
biosynthesis. and studies of their role in C d 2 + and Szmetabolism (Chs. 9-12), and model complexes: metalthiolate complexes and N M R studies of complexes with
adaniantane-like structures (Chs. 13 and 14). Other topics
covered include aurothioneins (Ch. 6), analysis for mercury
(Ch. 8). models of Cu“ proteins (Ch. 15), and metallodrugs
(Ch. 16).
The book gives comprehensive accounts of the present
state of knowledge in each of the areas treated. The treatment of “Optical Spectroscopy of Metallothioneins” in
Chapter 4 is especially interesting. So many results are presented here that one is confused at first, but the author goes
on to provide the interested reader with a clear picture of the
dynamics of cluster formation and the wide variety of metallothionein structures produced in this way. The picture is
completed by the article on “Kinetic Reactivity of Metallothioneins” in Chapter 7. On the basis of the results on
metal exchange reactions and ligand substitution the author
has succeeded in reaching a better understanding of the hitherto obscure function of thioneins in an organism. Four
further chapters deal with phytochelatins and cadystins.
Since these peptides have only been studied for about ten
years, some questions remain unanswered, for example concerning the relationship between sulfide metabolism and
production of phytochelatin. Also no clear picture of the
structures of these cadmium- and zinc-containing peptides
has yet emerged. since there have as yet been no single crystal
X-ray studies. Chapter 11 on “Meta1:sulfide Quantum Crystallites in Yeast” gives a suggested structure for the metal
centers in these sulfide-containing cadmium-binding proteins,
based on powder X-ray diffraction patterns. The article on
“Metal-Thiolate Compounds” (Ch. 13) reviews the latest
findings on coordination principles in synthetic metal -thiolate and metal sulfide-thiolate complexes. Readers seeking
a quick and straightforward summary of the latest developments in this area will much appreciate the clearly set out
table which lists all the new complexes synthesized in the last
six years. This chapter and Chapter 14 on “Adamantane-
Like Cages” together serve to bridge the gap between inorganic chemistry and biochemistry.
One of the book’s weaknesses is undoubtedly that the
potential of N M R spectroscopy only emerges in Chapter 14,
and no mention is made of the great importance of 3Cd‘HN M R spectroscopy in elucidating the three-dimensional
structures of metallothioneins. In recent years N M R spectroscopy has become such a powerful method in this area
that even the interpretation of X-ray crystallographic data
has had to rely on N M R results. The neglect of N M R spectroscopy is probably due to the fact that the book has developed out of papers presented at the symposium on “The
Chemistry of Heavy Metals in Physiologically Important
Roles” (Hawaii, 1989).
Altogether, this book is of interest to those involved in all
aspects of metallothionein research, as it is clearly presented
and contains nearly 1000 literature references which afford
easy access to the original publications. It should therefore
be available in every departmental library.
Hans-Oscar Stephaii
Fachbereich Anorganische und Festkorperchemie
der Universitat Duisburg (FRG)
Inorganic Polymeric Glassses. (Series: Studies in Inorganic
Chemistry, Vol. 15.) By R . C. Popp. Elsevier, Amsterdam,
1992. XIV, 322 pp., hardcover HFI 365.00.-ISBN 0-44489500-0
This book contains a useful survey of experimental results
on glass-forming phosphate systems, explaining clearly how
these relate to applications. Special attention is devoted to
the suitability of these materials for immobilizing and sealing
in radioactive wastes in the nuclear energy industry.
The introductory chapter deals with the fundamentals of
glass formation, the important properties that can be controlled by adjusting the process variables, and the main technological methods used in glass manufacture, including a
brief survey of aspects such as sol-gel technology and fiber
optics processes. However, the emphasis on phosphate glass-
es as inorganic polymeric glasses, thereby making a distinction between these and glasses made from other glass-forming systems, seems rather arbitrary, and can hardly be justified on structural grounds.
The main part of the book is concerned with efforts to
produce glasses with the highest possible chemical stability,
and with the analytical and diagnostic methods used to evaluate them. Much space is devoted to the resistance to hydrolysis and acids, and the effects of impurities (especially contamination from the crucible wall during melting) on the
properties, including the recrystallization and segregation
behavior, illustrated throughout by electron micrographs.
However, in the course of this the author makes some statements that are unsupported by experimental evidence and d o
not take into account other results reported in the literature.
Thus, he denies the existence of a specific mechanism for
internal diffusion in glasses of this type, whereas it is known,
for example, that Na@ions have a higher mobility in NaPO,
glasses than they d o at comparable concentrations in silicate
or borate glasses. As the book describes, glass-forming phosphate systems are used not only for encapsulating radioactive wastes but also in luminescent glasses, and the range
of uses is being further extended to medical applications
based on their proven biocompatibility ; for example, glasses
of this type or suitable glass ceramics can be used as bone
cements o r in dental prosthetics.
Each chapter ends with a bibliography listing important
original papers and, most usefully, review articles. This is a
monograph on a specialized field, in which a notable feature
is the thorough survey of knowledge on the inorganic structural chemistry of condensed phosphates.
The excellent layout makes the text quick and easy to
assimilate. The book will certainly be welcomed and used by
specialists in the field of phosphate-containing materials. It
has been produced using a computer text-processing program, and this becomes apparent especially in the diagrams,
which d o not always have the necessary captions. In view of
this, the rather high price seems surprising.
Adalberf Feltz
Institut fur Anorganische Chemie
der Universitat Jena (FRG)
New Books
see next page
Angeic. C ’ l ~ e r n Int.
.
Ed. Engl. 1993, 32, No. 9
(:> VCH VerlugsgesrNscl7ufi mbH, 0-69451 Weinheim, 1993
0570-0R33/93/0909-1375 S 10.00+ .25/0
1375
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properties, phytochelatins, shaw, metalцthiolate, complexes, iii, structure, synthesis, stillman, metallothionein, book, edited, review
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