Structure and Function of the Organic Matrix in the Nacreous Layer of Pinctada fucata

Abstract

The organic matrix in molluscan shells can be roughly divided into a water-soluble and a water-inso1uble matrix, those demarcation between which is sometimes not quite clear. Ca-binding components have been isolated from the water-soluble matrix [1,2]. Because of the capacity of such components for binding of Ca²⁺, many authors have postulated reactions whereby these molecules might promote nucleation of CaCO₃ crystals [3,4]. Although diversity of matrices has been reported by many authors [5, 6], the complete fractionation of such a matrix and the identificaiton of each component, contained in the matrix have not yet been achieved.