Studies On Benzo[A]Pyrene Mono-Oxygenase In The Shore Crab Carcinus-Maenas

A cytochrome P-450-dependent benzo[a]pyrene mono-oxygenase enzyme system (BPM) has been identified and partially characterized in males of the shore crab Carcinus maenas (L.). Apparent Km values obtained at 30 °C using microsomal preparations from the antennary glands of animals collected during summer were in the range 1.61–2.11 µM. The cytochrome P-450 content was 0·022 nmol/mg microsomal protein when BPM activity in the same preparation was 0·085 nmol/mg protein/min.

Induction Of Enzymes As A Mechanism For The Seasonal Control Of Metabolism In Marine-Invertebrates - Glucose-6-Phosphate Dehydrogenases From The Mantle And Hepatopancreas Of The Common Mussel Mytilus-Edulis-L

1. Glucose-6-phosphate dehydrogenase from the hepatopancreas and mantle tissue of M. edulis was investigated over two years for changes in specific activity (crude enzyme preparations) and the apparent Michaelis constants for G6P and NADP+ (highly purified enzyme preparations). 2. The specific activity of the mantle enzyme was low in summer and autumn and increased in the winter during the time of lipid deposition. In contrast, the specific activity of the hepatopancreas enzyme was high in summer and declined during the autumn and winter. 3. The apparent values for G6P and NADP+ of the mantle enzymechange little during a year. Changes were observed for the hepatopancreas enzyme during the first year but not the second.