|Distribution et importance quantitative de la chitine dans les coquilles de mollusques = Distribution and quantitative importance of chitin in mollusc shells|
Goffinet, G.; Jeuniaux, Ch. (1979). Distribution et importance quantitative de la chitine dans les coquilles de mollusques = Distribution and quantitative importance of chitin in mollusc shells. Cah. Biol. Mar. 20(3): 341-349
In: Cahiers de Biologie Marine. Station Biologique de Roscoff: Paris. ISSN 0007-9723, more
|Authors|| || Top |
- Goffinet, G., more
- Jeuniaux, Ch.
The wide distribution of chitin in the shells of Mollusca was confirmed by the application of a quantitative and specific enzymatic method. Chitin was found not only in cephalopod shells, but also in mother-of-pearl, pseudonacreous layers, and in many cases, in periostracum and prismatic layers of gastropod and bivalve shells. The presence and the proportion of chitin are highly variable in the periostracum of the bivalve species studied so far. Its permanent presence in the organic matrix, associated with mother-of-pearl, emphasizes the homology of this structure in the whole phylum of Mollusca. The more or less important participation of chitin in the building of the organic matrix of the different shell structures may be related to taxonomic and/or ecological characteristics. Chitin distribution is in good agreement with the classification grouping Arcidae and Glycimeridae among the Filibranchia Taxodonta and isolating Nuculidae in the Protobranchia, but the lower rate of chitin observed in the inner calcified shell layers of seven species of Anisomyaria and the high chitin rate in those of four species of Adapedonta may be a further indication of the homogeneity of both taxa. From an ecological point of view, chitin constitutes an important fraction of the shell organic matter in burrowing species, while this polysaccharide is practically lacking or in very low proportions in the shells of fixed or free species.