Biochemistry of Silicon and Related Problems

Silicon chemistry was initiated in 1823 by Berzelius who prepared elemental silicon. In many ways silicon was considered a typical opposite of carbon, although the two elements are closely related as to their electronic structure, both having four valence electrons. The properties of their compounds are, however, extreme- ly different. Both form extended structures, but in different ways - carbon by covalent carbon-carbon bonds; silicon by polar silicon- -oxygen-silicon bonds. The complex carbon compounds are integral parts of all living matter, plants and animals. The corresponding silicon compounds build up a major part of dead matter, soils and minerals. As recently as twenty years ago the title of this Symposium, "e;BiOChemistry of Silicon"e;, would have been considered as contradictio in adjecto. However, the development in the field has, during the past fifteen years, been overwhelming and has convinced us that silicon is a necessary element in the life processes, for animals as well as for plants. Interesting therapeutical uses have been suggested, but we have also become increasingly aware of serious occupational diseases - asbestosis and silicosis - and of possible cancerogenic effects. It is our hope that this volume will give some idea about various aspects of silicon compounds which were discussed during the Symposium.