[Morphogenetic features of Sulfobacillus thermosulfidooxidans]

The morphogenesis of Sulfobacillus thermosulfidooxidans BKM B-1269 was studied by electron microscopy at the vegetative stage of growth on a medium with pyrite as the source of energy. Young growing cultures of this organism were found to be very polymorphous: along with rod-like cells of various dimensions (0.6--0.8x1.0--3.0 mcm) which were predominant, coccoid, pyriform, clavate and dumbbell-like cells were also encountered. Certain cells have a tendency for branching. The cells can divide by sudden breaking of the parent cell along a partition being formed. These breaks are often incomplete, thus giving rise to cellular aggregates in the shape of palisades, bent chains, rings and Y-formations. The above characteristics of S. thermosulfidooxidans morphogenesis suggest that the genus Sulfobacillus is related to Corynebacterium-like organisms and actinomycetes. However, this genus differs in its morphology from bacilli though both (as well as actinomycetes) are capable of spore formation.