Abstract: | Cell suspensions of Chlorella vulgaris were found to possess the hydrogenase activity as was confirmed by their ability to absorb H2 in the presence of benzyl viologen, azocarmine and other hydrogen acceptors as well as to produce H2 from reduced methyl viologen. Incubation of the cells in the dark under anaerobic conditions in the atmosphere of H2, N2 or Ar stimulated the activity of hydrogenase and induced its de novo synthesis. Treatment of the cells adapted to anaerobiosis with dry ice or liquid nitrogen considerably increased their hydrogenase activity. The enzyme of the adapted cells was more resistant to the inactivation by O2 and temperature. |