Dynamics of sheet nacre formation in bivalves

Marthe Rousseau (1) , Anders Meibom (2) , Marc Gèze (2) , Xavier Bourrat (3) , Martine Angellier (3) , Evelyne Lopez (3)

1 BOME - Biologie des organismes marins et écosystèmes
2 Museum of Natural History
3 ISTO - Institut des Sciences de la Terre d'Orléans

Formation of nacre (mother-of-pearl) is a biomineralization process of fundamental scientific as well as industrial importance. However, the dynamics of the formation process is still not understood. Here, we use scanning electron microscopy and high spatial resolution ion microprobe depth-profiling to image the full three-dimensional distribution of organic materials around individual tablets in the top-most layer of forming nacre in bivalves. Nacre formation proceeds by lateral, symmetric growth of individual tablets mediated by a growth-ring rich in organics, in which aragonite crystallizes from amorphous precursors. The pivotal role in nacre formation played by the growth-ring structure documented in this study adds further complexity to a highly dynamical biomineralization process.

Mots clés: Biomineralization; Calcium carbonate; Nacre; SEM; SIMS

Domaines: Géochimie; Milieux et Changements globaux

Marthe Rousseau, Anders Meibom, Marc Gèze, Xavier Bourrat, Martine Angellier, et al.. Dynamics of sheet nacre formation in bivalves. Journal of Structural Biology, 2009, 165 (3), pp.190-195. ⟨10.1016/j.jsb.2008.11.011⟩. ⟨insu-00371791⟩