Iv. Grigolava et Jd. Mckenzie, CARBODIIMIDE-INDUCED LABELING OF SEA-URCHIN SURFACES (ECHINOIDEA, ECHINODERMATA), Comparative biochemistry and physiology. B. Comparative biochemistry, 110(3), 1995, pp. 477-482
A method for radiolabelling echinoderm body surfaces, using water-solu
ble carbodiimide was developed. The number of carboxyl groups reacting
with carbodiimide was estimated as 20 to 30 nmole g(-1) dry weight of
sea urchin spines. There were no phosphate groups accessible to carbo
diimide on the surface coat. Several enzymes were used to release boun
d radiolabel from the spines labelled with carbodiimide and radioactiv
e amino acid, Results obtained with proteases and hyaluronidase showed
that radiolabel was bound to the glycoprotein and/or protein molecule
s on the extracellular surface of the spine epidermis.