Abstract:
A study has been made of the general parameters of nitrogenise activity in the dark in the blue-green alga Anabaena cylindrical Lemm. It is concluded that he response of dark nitrogenase activity to hydrogen ion concentration and temperature is similar to activity in the light. Dark activity shows a definite optimum near 0.10 atm. oxygen. The major difference between dark and light activity is the transient nature of dark activity which has a half-life of 7-12 hours.