OBSERVATIONS ON THE MOTILITY AND THE STRUCTURE OF VITREOSCILLA

Abstract

Two strains of Vitreoscilla were studied. Their trichomes showed gliding motility on surfaces and they were immobile in fluid suspension. Motility is the property of the individual cells which make up the trichome, but floating, living cells rebounded when they touched a surface. A copious slime layer has been demonstrated and its possible roles in gliding motility is discussed. An association of the unique, scalloped, outer layer of the cell walls of these organisms with their curious motility suggested a new hypothesis: a vibratile, actively undulating surface. Specific antiserum caused rapid cessation of gliding motility; pasteurization and fixation prevented the rebound phenomenon. Stained preparations and electron micrographs of thin sections have provided a general description of structure. This shows, at least, that the classification of Vitreoscilla among the bacteria is reasonably founded. Similarities to certain bacteria are seen in the mode of cell division. On the other hand differentiation of central and peripheral cytoplasmic organization is reminiscent of the Myxophyceae, while the diffuse chromatin distribution has precedent in both groups.