This text focuses on the biological interactions of sulphur compounds which arise specifically from the presence of the sulphur atom within the molecule. The book opens with introductory chapters on the chemistry and biology of sulphur, before tackling the field by introducing compounds which share a common chemical combination. In general, following a description of the uses and impact upon the biological field, specific chemical group characteristics are discussed together with the biological activity and structure-activity relationships where known. The toxicity of such compounds, their consequences in biochemical and clinical terms, and their mechanisms of biological interaction are then addressed.

This book presents the latest findings on how plants respond physiologically to sulfur in their environment. It combines an ecosystems approach with new insights at the molecular and biochemical level. Key areas are explored to assess the functions and implications of this essential plant nutrient in a range of natural, semi-natural and anthropogenic environments. The result is an important new reference on the relationships between plants and sulfur.

Exposure of isolated hepatocytes to NaHS led to GSH depletion. CYP450 inhibitors were protective against NaHS toxicity and prevented GSH depletion. Methionine was protective against NaHS and its effect was overcome by inhibition of S-adenosyl-L-homocysteine hydrolase by adenosine. This suggests that S-adenosyhnethionine dependent methylation can detoxify H2S in the liver. The H 2O2 scavengers were protective against H2S toxicity. H2S induced ROS formation was dose dependent and pyruvate inhibited this ROS production. Nontoxic concentrations of H2S enhanced the cytotoxicity of H2O2 generated by glucose/glucose oxidase, which was inhibited by CYP450 inhibitors. Furthermore hepatocyte ROS formation induced by H2S was decreased by CYP450 inhibitors cimetidine and benzyleimidazole. Therefore CYP450-dependent metabolism of H2S is responsible for inducing ROS production. H2S induced cytotoxicity was preceded by mitochondrial depolarization. In this project, two aspects of the action of hydrogen sulfide and reactive sulfur species have been studied: cytotoxic and cytoprotective effects. Freshly isolated hepatocytes have been used in order to examine the prevalence and mechanisms of the different sulfide dependent processes that influence cell survival and death. Our hypothesis is that the exogenous application of high concentrations of HS and other reactive sulfur species to isolated hepatocytes in the presence of various modulators will provide a rapid mechanism dependent screen for ways in which reactive sulfur species can modulate cell survival and death. NaHS and/or garlic/onion derived organosulfur compounds, Allyl mercaptan (AM) and Propyl mercaptan (PM) protected hepatocytes against hydroquinone, methylbenzoquinone, and 5-hydroxynaphtoquinone. NaHS and mercaptans increased the cytotoxicity of tert-butylhydroquinone. Treatment of these benzoquinones with allyl mercaptan, propanethiol or NaHS led to formation of new compounds which by MS/MS analysis were identified as mercaptan conjugates of corresponding hydroquinones. (Abstract shortened by UMI.)H2S, allyl mercaptan (AM), propyl mercaptan (PM), diallyl disulfide (DADS) and diallyl sulfide (DAS) prevented hepatocyte toxicity induced by allyl alcohol, 1-bromoethanol and their toxic metabolites. MS/MS spectrometry revealed adduct formation between AM and/or PM with the acrolein and/or haloacetaldehyde formed by the metabolism of allyl alcohol and alpha-haloethanol. H 2S or garlic and onion mercaptans are cytoprotective by trapping toxic aldehyde metabolites and/or by preventing lipid peroxidation.

Sulfur is one of the most versatile elements in life. This book provides, for the first time, in-depth and integrated coverage of the functions of sulfur in phototrophic organisms including bacteria, plants and algae. It bridges gaps between biochemistry and cellular biology of sulfur in these organisms, and of biology and environments dominated by them. The book therefore provides a comprehensive overview of plant sulfur relations from genome to environment.

The third International Meeting on "Low Molecular Weight Sulfur Containing Natural Products,"sponsored by the International Union of Pure and Applied Chemistry, was held in the historical building of the Accademia Nazionale dei Lincei, Rome, Italy, June 18-21, 1979. The symposium was held in order to exchange knowledge in the intriguing and complex field of sulfur biochemistry. This theme brought together scientists from many speciali zed areas from organic and physical chemistry to biology and medicine. The interdisciplinary nature of the meeting gave to the participants the opportunity to discuss pro blems of common interest approached from different scienti fic standpoints. This volume contains 47 contributions presented at the meeting which mainly deal with new structural and metabolic aspects of sulfur biochemistry. An important aspect of such a scientific meeting is the rapid publication of the proceedings. Through the cooperation of the authors in providing "camera ready" copies of their manuscripts, the good efforts of the Orga nizing Committee, and the Plenum Press Publishing Co., it has been possible to publish this book within a few months of the meeting.

Biotechnology and Biology of Trichoderma serves as a comprehensive reference on the chemistry and biochemistry of one of the most important microbial agents, Trichoderma, and its use in an increased number of industrial bioprocesses for the synthesis of many biochemicals such as pharmaceuticals and biofuels. This book provides individuals working in the field of Trichoderma, especially biochemical engineers, biochemists and biotechnologists, important information on how these valuable fungi can contribute to the production of a wide range of products of commercial and ecological interest. - Provides a detailed and comprehensive coverage of the chemistry, biochemistry and biotechnology of Trichoderma, fungi present in soil and plants - Includes most important current and potential applications of Trichoderma in bioengineering, bioprocess technology including bioenergy & biofuels, biopharmaceuticals, secondary metabolites and protein engineering - Includes the most recent research advancements made on Trichoderma applications in plant biotechnology and ecology and environment

This volume contains fundamental knowledge regarding the structure and mechanisms of organic sulfur chemistry. Topics include sulfur bondings, effects of sulfur groups, stereochemistry around sulfur, substitution, ligand coupling within s-sulfurane, oxidation, reduction and rearrangement. References in this work total over 2,300. Anyone with an interest in organic sulfur chemistry will find this book to be fascinating reading.

his volume provides an organic chemical perspective on the biochemistry of sulfur compounds. The authors have applied the principles of various biochemical processes to a general theory of the biochemical phenomena of sulfur compounds. These processes include metabolisms of inorganic sulfur compounds and metalloenzymes, mechanisms of thiolesterase actions, functions of disulfides in proteins, and biochemical redox reactions. Organic Sulfur Chemistry: Biochemical Aspects is an ideal reference for students and researchers in both biochemistry and organic chemistry.