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There can be few elements with a biochemistry as coherent as that
of sulfur. This important element is crucial to myriad aspects of
metabo lism, catalysis, and structure. The plurality of functions
in which sulfur is involved derives squarely from the numerous
oxidation states in which it may exist, some having great
stability, some being capable of ready redox interconversions, and
yet others having great instability. As a result, the flux of
sulfur from the geosphere through the various kingdoms of life
leaves few biochemical processes unaffected. Although there are
large gaps in the fabric of our basic knowledge of sulfur
biochemistry, it is sufficiently framed to allow a unified and
organized story, a story which many of the best-known names in bio
chemistry have helped to write. It has been both a task and a
privilege to try and summarize this story, one that is enormous,
complex, fast moving, still developing and, above all, exciting. I
suppose that no mo nographer of such a vast subject could be
satisfied with his efforts. It is unfortunately probable that in
attempting this task I have made as many errors as a Stilton cheese
has blue streaks, and as many omissions as a Swiss cheese has
holes. Perfection is not to be achieved in a monograph. Inasmuch as
I have succeeded, the credit belongs to those whose efforts gave us
the knowledge we have. Where I have failed, the fault is only
mine."
Taurine, or 2-aminoethane sulfonic acid, has long been known to be
the major organic product formed from the breakdown of the
sulfur-containing amino acids, methionine and cysteine. It is
excreted as such in the urine or as bile acid conjugates in the
bile. Research over the last 25 years, however, has uncovered an
amazing variety of phenomena involving taurine. Despite the fact
that the mechanism of action of taurine in some of these phenomena
remains to be elucidated, it is clear that taurine is of far more
physiological relevance than being the mere metabolic debris of
sulfur amino acid catabolism. It also has numerous pharmacological
actions that are beginning to be developed, as exemplified by some
of the studies reported in this volume. This volume reports the
proceedings of the latest of a series of international symposia,
continuing on from the initial meeting held in Tucson, Arizona, in
1975. The latest symposium was the first to be held in Germany, in
Cologne from August 29 through September 1, 1993. It continued the
multidisciplinary approach that has been the norm for taurine
symposia. We hope the publication of the proceedings will stimulate
further investigations on this simple but fascinating compound.
I was pleased and at the same time filled with some misgivings when
Professors Alberto Giotti end Ryan Huxtable asked me to introduce
this book. The book is the outcome of the Symposium held in
Firenze-San Miniato (PI), October 6-9, 1986. The symposium was
entitled "Sulfur Amino Acids, Peptides and Related Compounds" and
was the 7th international symposium on taurine ssnd assooiated
substances. It is always difficult to introduce, with the right
brevity end emphasis, a topic which has been studied in depth by
numerous experte. Nevertheless, I shall do my best to give a
historical perspeotive of the subjects of the meeting which I
consider to be very important for the frontiers of researoh on
taurine. ~he following topios have also beoome coherent areas of
study during the development of researoh on taurine: metabolism,
nutrition, neurochemistry, cardiovasoular regulation. Although
taurine was isolated in 1821 by ~iedman and Gmel1n, its only
biochemioal role known at the time was the synthesis of bile saIte
in mammalian tissue. There has been an inoreasing interest in the
biologioal action of taurine from metabolio aspects to other
biologioal aspects (nutrition, development, eto.). In 1975 it was
first demonstrated that taurine deprivation produoed retinal
degeneration in cats; more reoent studies showed that a
taurine-free diet or the administration of taurine transport
inhibitors caused retinal degeneration in other mammlas. More
reoent studies have pointed out the role of taurine in development,
and the first part of this book is dedicated to these topios.
This volume comprises the edited proceedings of the International
Taurine Sympo sium held in Osaka, Japan, in June 1995, as a
Satellite Symposium of the 15th Biennial of the International
Society for Neurochemistry. This Taurine Symposium was the Meeting
latest in a series held since 1975 at approximately two-year
intervals by an informal group of international researchers. It
attracted contributions from 20 countries, ranging from Armenia via
Finland and Spain to the United States. Some 121 participants
attended. The Symposium was organized and chaired by Junichi Azuma,
University of Osaka. Other members of the Organizing Committee in
Japan consisted of Kinya Kuriyama and Masao Nakagawa, both from the
Kyoto Prefectural University of Medicine, and Akemichi Baba, from
Osaka University. The Committee had to contend with the disaster of
the Kobe earthquake, which struck on January 21. The epicenter was
only around 25 miles from the meeting site, and the quake
demolished the home of one Committee member. Despite this
unnaturally natural handicap, the participants experienced a
superbly organized meeting, one which more than maintained the high
social and scientific standards established for this series. In his
Welcome Message, Dr. Azuma listed a threefold objective for the
Symposium: To provide a forum for the interdisciplinary exchange of
information on taurine; to give an opportunity for renewing old
friendships and making new friends; and to promote coopera tion
among participants from around the world."
This volume is the selected, edited proceedings of the
International Taurine Sympo- th sium held in Tucson, Arizona, in
July 1997. The meeting was a satellite symposium ofthe 16 Biennial
Meeting of the International Society for Neurochemistry, which was
held in Boston immediately following the Tucson meeting. In view of
the desert location of Tucson, the meeting was advertised
tongue-in-cheek as being the hottest scientific meeting ever. As
the weather lived up to its billing, the Symposium may well have
earned the title. The meeting was held in an atmospheric cluster of
adobe buildings, old by the stan- dards of the American southwest,
at the Westward Look Resort in the Sonoran Desert foot- hills of
Tucson, which is overlooked by the 9000' high Santa Catalina
mountains. As is the norm for taurine symposia, participants formed
a multinational group, with representatives from China, Korea,
Japan, United States, Mexico, Venezuela, Ireland, England, Spain,
Italy, Finland, France, Denmark, Germany, Norway and Armenia. The
meeting was organized around plenary lectures by Russell Chesney
(University of Tennessee: Taurine and infant nutrition), Herminia
Pasantes-Morales (National Autono- mous University of Mexico:
Taurine: An osmolyte in mammalian tissues) and Kinya Kuri- yama
(Kyoto Prefectural University of Medicine: Interrelationship
between taurine and GABA).
Mitochondria from mammalian tissues possess an elaborate system for
2+ 2+ transporting Ca across their inner membrane which consists of
Ca import, 2+ via the Ca uniporter, in response to the
mitochondrial membrane 2+ + potential ?? and of Ca release by an
antiport system in exchange for H + 9,23 or Na (see Fig. l) .
Because the uniporter is dependent upon the external 2+ 2+ 2+ 2+ Ca
concentration ([Ca ]), mitochondria accumulate Ca until the [Ca ] o
o 2+ decreases to the level at which the uniporter activity
balances the Ca efflux. 2+ The [Ca ] at which the uniporter and
efflux activities are equal is defined o the "setpoint"
andcorresponds to values between 0.3-3M. 2+ Figure 1. The Ca
transport system of the inner membrane of mammalian mitochondria.
U, + 2+ + + uniporter. I, Na -independent efflux mechanism or Ca
/2H exchanger. D, Na -dependent 2+ + efflux mechanism or Ca /2Na
exchanger. PTP, permeability transition pore. FP, 11 flavoprotein.
?? membrane potential. ? pH gradient. Adapted from .
There is increasing recognition of the biological importance of
taurine. Disturbances in taurine metabolism are seen in
dysfunction- al states as diverse as epilepsy, cardiomyopathy,
Friedreich's ataxia and congestive heart failure, which combined
with the antiepi1eptic and cardiotonic actions of taurine
underscore the emerging clinical importance of this fascinating
substance. This is the third book to appear on taurine since 1976.
The last book (Taurine and Neuro1oeica1 Disorders, Raven Press,
1978) emphasized the involvement of taurine in central nervous
system phenomena. These actions are further explored in this
volume. In addition, nutritional aspects of taurine, particularly
as these re- late to development, have been increasingly recognized
to be im- portant parts of the taurine story. The marked emphasis
placed on nutrition by a number of contributors to this volume is
recognition of the meteoritic growth of this area. Are the
multitudinous actions of taurine differential expres- sions of a
universal mechanism? There is surprising unity of opinion expressed
by the scientists contributing to this volume, despite their
differences in viewpoint and background, as the reader, tanta-
lized we hope by this remark, will discover.
Mitochondria from mammalian tissues possess an elaborate system for
2+ 2+ transporting Ca across their inner membrane which consists of
Ca import, 2+ via the Ca uniporter, in response to the
mitochondrial membrane 2+ + potential ?? and of Ca release by an
antiport system in exchange for H + 9,23 or Na (see Fig. l) .
Because the uniporter is dependent upon the external 2+ 2+ 2+ 2+ Ca
concentration ([Ca ]), mitochondria accumulate Ca until the [Ca ] o
o 2+ decreases to the level at which the uniporter activity
balances the Ca efflux. 2+ The [Ca ] at which the uniporter and
efflux activities are equal is defined o the "setpoint"
andcorresponds to values between 0.3-3M. 2+ Figure 1. The Ca
transport system of the inner membrane of mammalian mitochondria.
U, + 2+ + + uniporter. I, Na -independent efflux mechanism or Ca
/2H exchanger. D, Na -dependent 2+ + efflux mechanism or Ca /2Na
exchanger. PTP, permeability transition pore. FP, 11 flavoprotein.
?? membrane potential. ? pH gradient. Adapted from .
This volume is the selected, edited proceedings of the
International Taurine Sympo- th sium held in Tucson, Arizona, in
July 1997. The meeting was a satellite symposium ofthe 16 Biennial
Meeting of the International Society for Neurochemistry, which was
held in Boston immediately following the Tucson meeting. In view of
the desert location of Tucson, the meeting was advertised
tongue-in-cheek as being the hottest scientific meeting ever. As
the weather lived up to its billing, the Symposium may well have
earned the title. The meeting was held in an atmospheric cluster of
adobe buildings, old by the stan- dards of the American southwest,
at the Westward Look Resort in the Sonoran Desert foot- hills of
Tucson, which is overlooked by the 9000' high Santa Catalina
mountains. As is the norm for taurine symposia, participants formed
a multinational group, with representatives from China, Korea,
Japan, United States, Mexico, Venezuela, Ireland, England, Spain,
Italy, Finland, France, Denmark, Germany, Norway and Armenia. The
meeting was organized around plenary lectures by Russell Chesney
(University of Tennessee: Taurine and infant nutrition), Herminia
Pasantes-Morales (National Autono- mous University of Mexico:
Taurine: An osmolyte in mammalian tissues) and Kinya Kuri- yama
(Kyoto Prefectural University of Medicine: Interrelationship
between taurine and GABA).
This volume comprises the edited proceedings of the International
Taurine Sympo sium held in Osaka, Japan, in June 1995, as a
Satellite Symposium of the 15th Biennial of the International
Society for Neurochemistry. This Taurine Symposium was the Meeting
latest in a series held since 1975 at approximately two-year
intervals by an informal group of international researchers. It
attracted contributions from 20 countries, ranging from Armenia via
Finland and Spain to the United States. Some 121 participants
attended. The Symposium was organized and chaired by Junichi Azuma,
University of Osaka. Other members of the Organizing Committee in
Japan consisted of Kinya Kuriyama and Masao Nakagawa, both from the
Kyoto Prefectural University of Medicine, and Akemichi Baba, from
Osaka University. The Committee had to contend with the disaster of
the Kobe earthquake, which struck on January 21. The epicenter was
only around 25 miles from the meeting site, and the quake
demolished the home of one Committee member. Despite this
unnaturally natural handicap, the participants experienced a
superbly organized meeting, one which more than maintained the high
social and scientific standards established for this series. In his
Welcome Message, Dr. Azuma listed a threefold objective for the
Symposium: To provide a forum for the interdisciplinary exchange of
information on taurine; to give an opportunity for renewing old
friendships and making new friends; and to promote coopera tion
among participants from around the world."
Taurine, or 2-aminoethane sulfonic acid, has long been known to be
the major organic product formed from the breakdown of the
sulfur-containing amino acids, methionine and cysteine. It is
excreted as such in the urine or as bile acid conjugates in the
bile. Research over the last 25 years, however, has uncovered an
amazing variety of phenomena involving taurine. Despite the fact
that the mechanism of action of taurine in some of these phenomena
remains to be elucidated, it is clear that taurine is of far more
physiological relevance than being the mere metabolic debris of
sulfur amino acid catabolism. It also has numerous pharmacological
actions that are beginning to be developed, as exemplified by some
of the studies reported in this volume. This volume reports the
proceedings of the latest of a series of international symposia,
continuing on from the initial meeting held in Tucson, Arizona, in
1975. The latest symposium was the first to be held in Germany, in
Cologne from August 29 through September 1, 1993. It continued the
multidisciplinary approach that has been the norm for taurine
symposia. We hope the publication of the proceedings will stimulate
further investigations on this simple but fascinating compound.
I was pleased and at the same time filled with some misgivings when
Professors Alberto Giotti end Ryan Huxtable asked me to introduce
this book. The book is the outcome of the Symposium held in
Firenze-San Miniato (PI), October 6-9, 1986. The symposium was
entitled "Sulfur Amino Acids, Peptides and Related Compounds" and
was the 7th international symposium on taurine ssnd assooiated
substances. It is always difficult to introduce, with the right
brevity end emphasis, a topic which has been studied in depth by
numerous experte. Nevertheless, I shall do my best to give a
historical perspeotive of the subjects of the meeting which I
consider to be very important for the frontiers of researoh on
taurine. ~he following topios have also beoome coherent areas of
study during the development of researoh on taurine: metabolism,
nutrition, neurochemistry, cardiovasoular regulation. Although
taurine was isolated in 1821 by ~iedman and Gmel1n, its only
biochemioal role known at the time was the synthesis of bile saIte
in mammalian tissue. There has been an inoreasing interest in the
biologioal action of taurine from metabolio aspects to other
biologioal aspects (nutrition, development, eto.). In 1975 it was
first demonstrated that taurine deprivation produoed retinal
degeneration in cats; more reoent studies showed that a
taurine-free diet or the administration of taurine transport
inhibitors caused retinal degeneration in other mammlas. More
reoent studies have pointed out the role of taurine in development,
and the first part of this book is dedicated to these topios.
There can be few elements with a biochemistry as coherent as that
of sulfur. This important element is crucial to myriad aspects of
metabo lism, catalysis, and structure. The plurality of functions
in which sulfur is involved derives squarely from the numerous
oxidation states in which it may exist, some having great
stability, some being capable of ready redox interconversions, and
yet others having great instability. As a result, the flux of
sulfur from the geosphere through the various kingdoms of life
leaves few biochemical processes unaffected. Although there are
large gaps in the fabric of our basic knowledge of sulfur
biochemistry, it is sufficiently framed to allow a unified and
organized story, a story which many of the best-known names in bio
chemistry have helped to write. It has been both a task and a
privilege to try and summarize this story, one that is enormous,
complex, fast moving, still developing and, above all, exciting. I
suppose that no mo nographer of such a vast subject could be
satisfied with his efforts. It is unfortunately probable that in
attempting this task I have made as many errors as a Stilton cheese
has blue streaks, and as many omissions as a Swiss cheese has
holes. Perfection is not to be achieved in a monograph. Inasmuch as
I have succeeded, the credit belongs to those whose efforts gave us
the knowledge we have. Where I have failed, the fault is only
mine."
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