Energy-dependent cell cohesion in myxobacteria.

Cohesion in the myxobacterium Stigmatella aurantiaca was characterized. Two classes of cohesion were revealed, termed class A and class B. Class A cohesion is a characteristic of vegetative cells grown in tryptone or casitone (Difco Laboratories, Detroit, Mich.), whereas class B cohesion requires the addition of calcium ion for induction. Class A cohesion occurs in the presence of any cation and is temperature independent. Class B cohesion requires the presence of a cation in the calcium group and is energy dependent. We conclude that S. aurantiaca responds to calcium ion by synthesizing the molecular components of a system of cell cohesion (class B) and that the functioning of this system requires the expenditure of metabolic energy.