Physiological performances of the blue-green alga Anacystis nidulans in continuous turbidostat fermenter culture

Abstract

A sterile continuous turbidostat culture in a 2-1 fermenter was used to systematically measure the gas exchange rates of Anacystis nidulans in a highly turbulent system under strictly controlled environmental conditions. An extensive physiological characterization of Anacystis is given in terms of photosynthesis rates (CO2 uptake and O2 evolution) and dark respiration rates as function of different parameters such as stirrer speed, temperature, CO2 and O2 concentration, light intensity, culture density and pH. Steady state ATP levels and apparent photophosphorylation rates complete the performance data. The dependence of the photosynthetic quotient from the parameters enables a physiological characterization of the light dependent nitrate assimilation.