[Electron microscopic study of meningococci in stab cultures]

The study of the ultrastructure of meningococci (strain C0638) in the process of submerged batch cultivation permitted the authors to follow changes in the fine structure of these microorganisms in different phases of the growth of the culture. Thus, the meningococcal populations retained their ultrastructure most intact during the exponential phase and the growth rate deceleration phase. During these growth phases a faintly pronounced reaction of the surface structures with ruthenium red was observed. In the stationary phase and in the atrophy phase this reaction was completely absent. The accumulation of exotoxin bubbles in the membrane was shown to achieve its maximum in the atrophy phase; besides, these structures regularly appeared at the death of the cells under the action of alkali. A hypothesis explaining the appearance of these bubbles is put forward.