Novel surface polymer changes in development of Myxococcus spp.

Abstract

THE Myxobacteriaceae are unique among prokaryotes in their development cycle. Vegetative cells are Gram-negative bacilli which undergo binary fission as in other prokaryotes; alternatively, the cells can aggregate on solid surfaces to form fruiting bodies in which the bacteria undergo conversion to myxospores. In Myxococcus xanthus and related species a simple fruiting body is formed in which spherical myxospores are surrounded by extracellular polysaccharide slime¹. In at least one strain of M. xanthus, synchronous myxospore formation can be obtained in liquid culture through induction with glycerol and other agents². The entire bacillus undergoes conversion to the myxospore form; there is no apparent loss of cell material such as is observed in the morphogenesis of Gram-positive bacilli to endospores at the expense of cell wall and surface material shed on emergence of the mature spore. The fate of the Myxococcus surface polymers is thus of particular interest.