Nitrogen Fixation by the Photosynthetic Sulfur Bacterium Chlorobium phaeobacteroides from Lake Kinneret

N(2) fixation by Chlorobium phaeobacteroides from Lake Kinneret was dependent on ammonia concentration and light intensity. In the thermocline of Lake Kinneret, N(2) fixation and photosynthesis were low. It was concluded that the bacteria do not contribute significantly to the organic nitrogen load of the lake.