Physiological Characterization of Cyanophora paradoxa, a Flagellate Containing Cyanelles in Endosymbiosis
نویسندگان
چکیده
Culture conditions are described under which Cyanophora paradoxa grows with a generation time of less than two days. The organism is an obligate photoautotrophic flagellate unable to degrade exogenous carbohydrates via respiration. It does not synthesize nitrogenase but can form a hydrogenase with similar properties as in blue-green algae. The photosynthetic 0 2-evolution pro ceeds with essentially the same rate as in green or blue-green algae. Besides C O , , p-benzochinon, nitrate and nitrite also stimulate the photosynthetic 0 2-evolution. Nitrite reduction is strictly lightdependent where the stoicheiometry between nitrite-disappearance and photosynthetic 0 2-evolution is 1:1.5. It is concluded that the cyanelles supply the eucaryotic host both with carbon and nitrogen compounds.
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