[Complex spherical bodies of Thermus ruber]

Thermus ruber produces complex spherical bodies during its growth on liquid organic media. These bodies are similar to those formed by T. aquaticus. Giant spheres of T. ruber can reach 30 mc in diameter. They may originate by two pathways: (1) from cell aggregates or (2) by local separation of the outer layer of the cell wall which accompanies bending of a cell or a bundle of cells (threads) in the form of a hook, a loop or a vibrio. In both cases, the spheres grow as a result of cell multiplication under the common outer layer of the cell wall. Their growth on a potato-peptone broth is favoured by an addition of DL-alpha-alanine at a concentration of 10 mcg per 1 ml. Apparently, these complex spheres are sort of swimming bladders which are formed by an organism to occupy horizons with favourable oxygen regime during their growth in an aqueous medium. When the spheres are incubated under stationary conditions for a long time, they become setaceous and transform into coils.