A report on the Fourth International Symposium on Bio-Mineralization

Abstract

Bio-mineralization, quite curiously, has been effectively ignored by the inorganic chemist who is interested in biology. This short review of the program of the Fourth International Symposium on Bio-Mineralization is presented here in an effort to inform inorganic biochemists of the fascination clearly felt for this subject by the participants at the conference. It has obvious implications for the study of nonbiological inorganic solids and composites. The first papers were concerned with the so-called Gaia hypothesis [ 11. This states that much of the outer layers of the earth, including the atmosphere, the sea, and considerable parts of the earth’s surface to a depth of a few miles in places, is of a homeostatically controlled chemical composition and has a temperature regulated through the greenhouse effect of carbon dioxide [2]. The control is due to biological activity and the observed composition and temperature are remote from that which would have arisen from inanimate activity. The major proponent of the hypothesis, Lovelock, opened the discussion with a survey. He and others could point to the steady state composition of the earth’s atmosphere, with its low CO, and high N, andO,, which contrasts markedly with that of other planets, as a clear example of a biologically generated and moderately stable part of the earth. The extension of the discussion to the aquatic environment was not so easily accepted but a large test experiment is underway by Margulis, another supporter of the basic idea [I]. The huge chemical reactions of the ocean vents at the edges of the continental plates and the immense effects of erosion of the land mass led Garrels to doubt that there was a real homeostasis. He pointed out that the carbonate, for example, which was being transferred in the overall nonbiological reaction