FIG. 1.
T. vaginalis growth is arrested by DAB, and putrescine restores growth to DAB-treated parasites. (A) TYM-serum medium was inoculated with mid-logarithmic-grown organisms at a density of 105 per ml in the presence of different concentrations of DAB, as indicated in the insert. Numbers of organisms were enumerated at different times of growth. (B) Trichomonads treated with 20 mM DAB and grown as in panel A for 18 h were supplemented with or without 40 mM putrescine, 50 μM spermine, or 50 μM spermidine. (C) Trichomonads were grown in high (H)- or low (L)-iron medium in the absence (control H and L Fe) or presence of 20 mM DAB. In this case the DAB-treated parasites were grown in normal medium (normal Fe) or in a high-iron (H Fe) or low-iron (L Fe) medium, as indicated in the inset and as detailed in Materials and Methods.