title: Ion metabolism in a halophilic blue-green alga, Aphanothece halophytica.
abstract: The intracellular ion content of the halophilic blue-green alga, Aphanthece halophytica was studied as a function of age, external sodium and external potassium concentration. Intracellular Na+ was found to be about 0.38 millimoles/g dry mass. Intracellular K+ concentrations were as high as 1 M and varied directly with external salinity. Intracellular Ca++ and Mg++ were in the range previously reported for fresh water blue-green algae despite their extremely high extracellular concentrations. Average cell size is consistent at room temperature with two exceptions. When the outside K+ is lower than 6.5 mM the cells tend to be smaller with less intracellular K+ and high Ca++. In stationary phase cultrues the cells are larger with high intracellular Mg++ and low K+.
mesh_terms: D002118:Calcium / Q000378:metabolism; D000458:Cyanobacteria / Q000378:metabolism*; D005110:Extracellular Space; D007477:Ions / Q000378:metabolism*; D008274:Magnesium / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride / Q000378:metabolism
chemical_list: D007477:Ions; D012965:Sodium Chloride; D012964:Sodium; D008274:Magnesium; D011188:Potassium; D002118:Calcium