Qualitative Chemical Composition of the Calcifying Organic Matrix obtained from Cell-free Coccoliths

Abstract

BIOLOGICAL mineral deposition has been defined as a biphasic process comprised of an organic matrix on which specific minerals are deposited¹. Investigations with the euryhaline supralittoral coccolithophorid Hymenomonas Mary Parks 156 have shown that this primitive and ancient protist fulfils all the requirements of biological calcification in its production of calcitic coccoliths^2–4. The fact that Hymenomonas extrudes a large number of its coccoliths as it ages and that simple manipulation of the cultures³ permits collection of the extra- and intracellular calcareous bodies makes these organisms exceptional test objects for an investigation of the physiology and intimate chemistry of biological mineral deposition.