The Journal of Medical Microbiology, Vol 8, Issue 2 349-355, Copyright © 1975 by Society for General Microbiology
T-mycoplasmas: a study of the morphology, ultrastructure and mode of division of some human strains
J. Whitescarver and G. Furness
The morphology of 10 strains of T-mycoplasma was studied in wet
preparations of viable cells by darkfield, phase-contrast and interference
microscopy, and in fixed preparations by various techniques of electron
microscopy. Mycoplasma-like artefacts in the horse-serum component of the
medium were eliminated by filtration. All 10 strains were similar.
Individual cells were spherical, 0-25-1-0 mum in size, with a bounding
trilaminar membrane, 10 nm thick and containing 7-5-12-5-nm particles, and
a layer of pilus-like projections, 5-8 nm long, on the outer surface. A
possible capsular matrix was observed only by the pseudoreplica technique.
The cells contained 12-15-nm ribosomes, nuclear fibroids 7-5-9 nm wide, and
vacuoles. During replication, the cell elongated slightly and the ribsomes
migrated to the ends of the cell leaving a ribosome-free area into which
the bounding membrane invaginated to form a bud. The bud eventually
separated by completion of the process of invagination; a cross-septum did
not form. Usually only a single bud developed but sometimes two appeared
simultaneously.
