External Factors Influencing Light-Induced Hydrogen Evolution by the Blue-Green Alga, Nostoc muscorum
نویسندگان
چکیده
This study was conducted to determine some physiological conditions which influence light-in duced hydrogen evolution by intact cells of the blue-green alga Nostoc muscorum. This activity was found to be dependent on the age of the culture, cultivation temperature, ageing of the cells, and on gassing the cultures with nitrogen or air. Nitrogenase is particularly ac tive after cultivation at 22 °C but not at 32 °C although growth is about the same. The molar ratio of acetylene reduction to hydrogen evolution both gas exchanges obviously catalyzed by nitrogen ase is also dependent on age and temperature of the culture. A hydrogen-consuming („up take“) hydrogenase activity is present and affected by prolonged microaerobic, but not by aerobic growth conditions, and stimulated by light. External factors during growth apparently influence differently the activities of nitrogenase and uptake hydrogenase. Consequently besides the electron donor supply net light-induced hydro gen evolution by intact cells is dependent on these two variable activities.
منابع مشابه
Isolation and properties of alpha granules and ribosomes from a blue-green alga, Nostoc muscorum
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