SOLID-STATE BIOINORGANIC CHEMISTRY - MECHANISMS AND MODELS OF BIOMINERALIZATION

The chapter provides an overview of recent advances in solid-state bioinorganic chemistry. Although the study of biomineralization has received much attention from biologists, geologists, and medical scientists, the structure and function of inorganic solids in biological systems has only recently been perceived as an important aspect of bioinorganic chemistry. The chapter reviews the structural and biochemical aspects of two contrasting biological systems involving silicification in (1) intracellular vesicles and (2) extracellular polysaccharidic matrices. Alternatively, the surface silica may be preferentially protected by an organic membrane. The initial centers become increasingly demineralized with time until they extend and join along the central axis, forming tubular, brittle rods. As demineralization increases, the hollowing becomes more extensive, and only at the later stages, the outer edges of the costal rods show signs of demineralization, becoming rough and pitted. Binding of silicic acid to organic molecules can occur through hydrogen bonding, ionic interactions, or condensation of OH groups. © 1991 Academic Press, Inc.