High opine dehydrogenase activities in crustacean species at deep-sea hydrothermal vents

Opine dehydrogenase (OpDH) activities in ten benthos taxa at deep-sea hydrothermal vents were analyzed. Although the type and strength of the activity detected differed among taxa, OpDH activity was observed in all specimens. Particularly high activities were detected in Aphroditoidea sp. (strombine dehydrogenase 24.07 units g−1; alanopine dehydrogenase 15.08 units g−1). Furthermore, high OpDH activities were detected from two crustacean species. Activities of tauropine dehydrogenase (3.08 units g−1), β-alanopine dehydrogenase (0.97 units g−1), and strombine dehydrogenase (0.69 units g−1) were detected in neoverrucid barnacle Neoverruca intermedia Sha & Ren. In caridean shrimp Opaepele loihi Williams and Dobbs, strombine dehydrogenase (7.21 units g−1), alanopine dehydrogenase (1.37 units g−1), and tauropine dehydrogenase (3.03 units g−1) activities were detected. A previous report has shown that crustacean species have no or very low OpDH activity levels. Therefore, this is the first report of the detection of high OpDH activities in Crustacea.