Effect of Sodium on Phosphate Uptake in Unicellular and Filamentous Cyanobacteria

摘要

The effect of Na+on phosphate uptake was studied in four strains of cyanobacteria:SynechococcusPCC 7942,GloeothecePCC 6501,Phormidiumsp. andChlorogloeopsisPCC 6912. Phosphate uptake was stimulated by Na+in all cases. Li+and K+acted as partial analogues for Na+. Half-saturation K1/2(Na+) of phosphate uptake was reached with Na+concentrations ranging from 317μMinChlorogloeopsisto 659μMinPhormidium. The concentration of phosphate required to reach half-saturation of phosphate uptake K1/2(Pi)was not changed by the presence of Na