Based Biominerals — Calcium Carbonates in Ascidians and Molluscs

CALCIUM-BASED BIOMINERALS CALCIUM CARBONATES IN ASCIDIANS AND MOLLUSCS 

ANTIPARALLEL 0-SHEET Of Ok PLANE OF ARAGONITE 0-CHlTIN FIBER 

The shells of molluscs, such as clam, oyster abalone, scallop and fresh water snail, use CaC03 as the principal constituent for an extraordinary array of diverse structures. Several approaches have led, and will lead further in the future, to a greater understanding of how these complex forms are generated. 

The final approach is to use a combination of microarray techniques, antisense oligonucleotides, functional tests and the use of monoclonal antibodies to identify matrix proteins and families of matrix proteins involved in the biomineralization process, and ultimately to establish their function. The recent publication of the genome of the sea urchin 

Strongylocentrotus purpuratus represents a promising start to the bioinformatic approach for the identification, characterization and functional analysis of particular molecules of the matrix involved in biomineralization. 

Calcium-Based Biominerals — Calcium Carbonates in Ascidians and Molluscs 

A NT parallel 3-SHEET OF SILK-FIBROIN-LIKE protein 

FIGURE 19.14 Scanning electron micrographs of spicules from the tunicate, P. pachydermatina. (a) Dogbone spicule from the tunic, (b) Antler spicule from the branchial sac. 10-pm scale bars are shown on the figures. Note the scale differences. (Fmm Wilt, 2005. Copyright 2005 with permission from Elsevier.) 

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