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Life Sciences for the 21st Century.

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course, most important are the radial
breathing mode and the double-peak
structure just below 1600 cm 1, which
together confirm the presence of nanotubes in any given sample. However,
the radial breathing mode alone is not
sufficient evidence for nanotubes.
Next, the authors consider the orientation of isolated tubes or aligned samples,
and describe how these properties can
be determined from the Raman signal,
since the signal is strongest when the
incoming light is polarized parallel to
the nanotube axis. The authors also conclude that diameters can be estimated
from the frequency of the radial breathing mode. As far as chiral angle and indices are concerned, it is found that the
uncertainty in diameter is too large to
assign n1 and n2 on the basis of the
Raman data alone. A different situation
exists for defect concentrations, which
can be deduced from the ratio of the
intensities of the D and D* peaks.
Whereas the broad peak around
1540 cm 1 is a good indicator for metallic
nanotubes, the identification of semiconducting nanotubes still remains controversial. Finally, the strain of nanotubes
can be determined from a shift in
phonon frequency (at fixed excitation
energy), which results from a change in
the bond lengths and/or angles. Although
in principle possible, the authors decide
that the determination of the band gap
fails, since the typical band gaps below
1 eV are too small for standard lasers.
In summary, all the chapters of
Carbon Nanotubes are solid, comprehensive discussions of the basis concepts
and physical properties of this form of
carbon. Each chapter begins with an
excellent introduction to the topic concerned, which is followed by a good
overview of the subject and more details
for the expert in the area. The chapters
should prove very useful to both students and researchers in the different
areas. I would recommend this book to
practicing chemical physicists and physical chemists as well as to readers
broadly interested in nanoscience.
Dirk M. Guldi
Institut fr Physikalische Chemie
Friedrich-Alexander-Universitt Erlangen
(Germany)
5878
Life Sciences for the 21st Century
Edited by Ehud
Keinan, Israel
Schechter, and
Michael Sela. WileyVCH, Weinheim
2003. 356 pp.,
hardcover
E 44.90.—ISBN
3-527-30588-2
This book is the second in a threevolume series that started with a
volume on chemistry and will be completed by one on physics and mathematics. In this volume Ehud Keinan, Israel
Schechter, and Michael Sela (of Technion—the Israel Institute of Technology,
and the Weizmann Institute of Science)
have asked scientists to review their
achievements and give their views of
the prospects in their areas of the life
sciences.
The 16 reviews cover a selection of
topics that reflect recent discoveries in
life science. Starting with RNA, which
is suggested to have been the origin of
all life, the book discusses recent advances in basic scientific research, on topics
such as protein synthesis, protein degradation by the proteasome, cell signaling,
and protein interactions. It also includes
novel genetic approaches to the development of medical therapies, and plant
biotechnology based on research
during the 20th century.
After 50 years of research concentrated on DNA, which culminated in
the sequencing of the human genome,
in the 21st century the focus has shifted
to RNA as the nucleic acid species of
particular interest. One review by
Gerald Joyce discusses the synthesis,
modulation, and self-replication capability of RNA, which gives it the potential to act as the carrier of information
for the origin of replicating life on
earth. There is strong evidence that
RNAs thereby served as synthase ribozymes to synthesize their own building
blocks. Some of those reactions, including activation and ligation of the building blocks to form oligomers, have
already been proven in vitro to be possible. Furthermore, it is well known that
different RNA species are capable of
6 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
performing a variety of chemical reactions, including peptide-bond formation.
A remnant of this RNA world in our
cells is certainly the ribosome, a protein
synthesis machinery that consists mainly
of catalytic RNA, tRNAs, and ribozymes. Ada Yonath summarizes the
amazing progress that has been made
during the last 20 years on the structural
and functional determination of such a
large biological complex.
Moving on from the world of RNA
and its role in protein synthesis, other
chapters focus on the mechanism by
which proteins are prepared for their
subsequent intracellular degradation,
and the ubiquitin–proteasome pathway
is explained. Until the late 1980s, the
subject of protein degradation was
more or less neglected, since no organelle had been identified as being responsible for the degradation of cytoplasmic
proteins. We now know that this is a
complicated pathway, which starts with
the labeling of the proteins with ubiquitin, a small polypeptide of 76 amino
acids, thus guiding them to the proteasome, a large protein complex bearing
many protease activities. The chapters
by Aaron Ciechanover and Michael
Glickman describe in detail the structural requirements and the function of
this pathway. Besides its function in the
degradation of endogenous proteins, as
determined by their turnover, the proteolysis pathway is also very important
in the degradation of antigens and
their recognition by our immune
system. In general, protein modifications occurring after their synthesis
often change the cellular fate of the protein or trigger a variety of signaling cascades, such as the phosphorylation process described in Chapter 6 by
Edmond Fischer, and that described in
Chapter 8 by Tony Hunter. It is now
known that communication between
cells, or between cells and their environment, occurs by signaling processes or
cascades that require the rapid modification of transmembrane and intracellular proteins that cross-talk with each
other to transfer a signal from the outside of the cell into the inside, where it
will start a response mechanism. From
results of research in the last 20 years,
this communication pathway has
turned out to be very sophisticated and
complex. Even though many aspects of
Angew. Chem. Int. Ed. 2004, 43, 5877 – 5879
Angewandte
Chemie
these communication pathways have
been explained, many questions still
remain unanswered; for example, it is
not clear how stem cells communicate
with the environment to change their
cellular fate. If these signaling cascades
are disturbed by the inhibition of protein modification, as has been described
for some pathogens and toxins that
inhibit protein phosphorylation, immunogenic recognition of those pathogens
is prevented, thus resulting in various
diseases. Furthermore, there are many
human diseases based on genetic defects
that influence signaling cascades, including non-insulin-dependent diabetes, but
in many cases no therapeutic treatment
is available. There is no doubt that this
field will continue to advance during
the next 20 years.
A major breakthrough in clinical
research of the last 10 years was the
development of novel vaccines encoded
by non-infectious and genetically engineered proteins and peptides, as described in Chapter 9 by Michael Sela
and Ruth Arnon. This technique
makes it possible to prevent infections
by many bacterial toxins or by certain
viruses. Toxin proteins such as the cholera toxin or certain viral proteins are
dissected into peptides, and each peptide is introduced to the body to test
the generation of functional antibodies,
thereby reducing the risk of unwanted
infections, as had occurred in the past.
However, many viruses undergo rapid
mutagenesis, which makes it impossible
to produce vaccines based on large
viral proteins. Therefore, the long-term
goal is to identify conserved peptide
sequences so as to produce a vaccine
that is effective for all viral strains. As
well as research on vaccines against bac-
Angew. Chem. Int. Ed. 2004, 43, 5877 – 5879
terial, viral, and pathogenic infections,
the chapters describe initial approaches
towards applying peptide vaccines
against autoimmune diseases and
cancer.
Following that section on genetic
engineering of vaccines, Chapters 10–
15 focus on a variety of genetic manipulations and their applications in stemcell biology and cell replacement therapy, and in plant and food biology, e.g.,
for the optimization of plant growth,
structure, texture, and resistance to
pathogens. Some of these chapters concentrate on reviewing the science and
technology, whereas others are paired
with overviews of historical and economic developments, especially for the
food industry.
The book ends with a theoretical and
mathematical review on population
dynamics, comparing evolutionary and
classical game theory with the behavior
dynamics of large populations, such as
viral mutagenesis, environmental adaptation processes, and epidemiology.
The chapter by Martin Novak and Karl
Sigmund introduces the reader to theoretical biology in a clear and easily
understandable way, and discusses the
future role of theoretical biology in predicting diseases and biological function,
even bringing together mathematics,
biology, medicine, and ecology. All the
topics reviewed in the book will certainly influence life science in the current century, although this selection is
far from being complete.
The book provides the general
reader with clear explanations of molecular processes and emerging technologies, and shows how life science continues to alter our understanding of the
origin of life and diseases in the 21st cen-
www.angewandte.org
tury. As well as summarizing major discoveries, it describes how genetics
offers a wealth of possibilities to alter
the human condition—from genetically
modified foods to genetically modified
cells and vaccines—and has transformed
itself from a domain of pure research
into one of big business as well.
Although, at a first glance, the book
is perhaps not as attractive as others in
this area because of its shortage of
good illustrations, it is certainly nicely
structured. Most chapters and reviews
are easily understandable by a broad
readership, including chemists, biologists, physicians, physicists, and pharmacologists. However, some of the reviews
are filled with too many details. In particular, Chapter 1 by Ada Yonath, with
its wealth of detailed structural information, lacks suitable graphics to guide the
reader through these massive amounts
of data. To enjoy this chapter the
reader is recommended to first read
Chapter 3, which deals with the origin
of life, and to return to Chapter 1 at a
later time.
In summary, the book is without any
doubt very stimulating and informative
for all scientists who wish to get a
quick view of some of the major current
topics of life science without having a
special scientific background in each
area.
Ute Schepers
Kekul:-Institut fr Organische Chemie
und Biochemie
Universitt Bonn (Germany)
Monograph on Biological Chemistry
DOI: 10.1002/anie.200385135
6 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
5879
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