[Formation and structure of oval aggregates of Erwinia herbicola cells]

Formation and structure of oval aggregates were studied by electron and light microscopy of the cells of Erwinia herbicola. Some cells in these cultures were found to synthesize extracellular slime which caused the formation of the aggregates. As has been established by cytochemical techniques, the slime consists mainly of polysaccharides. The aggregates are compact groups of cells submerged into the slime whose bulk is located at the periphery. Formation of slime synthesizing cells in the cultures of Erwinia herbicola presumably does not depend on the composition of growth media and the age of the culture.