OCCURRENCE OF FREE D-ASPARTATE AND ASPARTATE RACEMASE IN THE BLOOD SHELL SCAPHARCA-BROUGHTONII

Substantial concentrations of D-aspartate were found in several tissue s of Scapharca broughtonii together with approximately equal concentra tions of L-aspartate. The foot and mantle extracts also contained an a spartate racemase activity. The formation of L-aspartate from the D-en antiomer by the foot extract was apparently slower than the reverse re action, and this unbalance seemed to be due to the presence of an enzy me activity which rapidly converted L-aspartate to L-alanine. The poss ible role of D-aspartate in the anaerobiosis was discussed.