TRICHOMONAS VAGINALIS DONNE 1836: ITS MORPHOLOGIC CHARACTERISTICS, MITOSIS AND SPECIFIC IDENTITY1

Abstract

T. vaginalis, the type sp. of the genus, has a neuromotor system consisting of an anteriorly located blepharoplast, a rhizoplast between the blepharo-plast and nucleus, 4 anterior flagella, an undulating mem-brane, chromatic basal rod, parabasal fibrils, and axo-style. The blepharoplast contains 5 granules, to which the other components of the neuromotor system are attached in definite and constant fashion. The axostyle is hyaline, but slightly siderophile, and functions as a skeletal structure and as an organ of attachment. Radical autotomy occurs in both the vaginal secretions and in culture, and this explains the appearance of small individual organisms with full-length undulating membranes. Four chromosomes appear in mitosis. A para-desmose connects the daughter blepharoplasts, which function as centroblepharoplasts during division. Two flagella go to each daughter individual in division. Two new flagella grow out of each blepharoplast to restore the full number of 4. The old undulating membrane, chromatic basal rod, and parabasal fibril go with one daughter blepharoplast at division, and these structures grow out anew from the other daughter blepharoplast. The old axostyle degenerates during division and new daughter axostyles grow out of each daughter blepharoplast between the metaphase and telophase of mitosis. Duplex individuals are occasionally seen. Trichomonas vaginalis, T. buccalis, and T. hominis retain their species identity in culture. T. vaginalis is morphologically distinct from T. buccalis and from the intestinal tricho-monads of man.