Calcium in Cell Walls of Rhizobium trifolii

Abstract

The cell walls from Rhizobium trifolii (grown under both "normal" and "calcium-deprived" conditions) were analyzed in an attempt to detect a chemical cause for the apparent weakness or looseness of the walls in calcium-deprived organisms. The organic components typical of gram-negative cell walls were present in normal and calcium-deprived cells. The latter concentrated most of the small amount of available calcium in the walls which, however, contained only 60% of that present in the walls of normal organisms. Magnesium was not able to substitute for calcium as a wall component.