The Effect of Reducing and Other Agents on the Motility of Treponema pallidum in an Acellular Culture Medium

Abstract

443The maintenance of Treponema pallidum motility was investigated in an acellular medium based on T. pallidurn immobilization test medium. The acellular medium contained cysteine, glutathione, thioglycollate and dithiothreitol as reducing agents and had a redox potential of -275 & 25 mV at pH 7.3. In an atmosphere containing 3 % 02, motile treponemes survived four times longer when calf serum and bovine serum albumin were added to the medium. The selective omission of glutathione and, particularly, thioglycollate prolonged the survival of motile treponemes almost fivefold. In addition, stored medium, in which thioglycollate had become inactive, sustained motile treponemes for longer than did freshly prepared medium. Thus, thioglycollate is toxic for the organisms. It may be omitted from the medium because low redox potentials can be achieved without it.

In vitro cultivation of Treponema pallidum: independent confirmation

“…Their system utilized a combination of several important elements which had been previously investigated in their own laboratory and by others, including (i) monolayer cultures of a slow-growing mammalian cell line, SflEp cottontail rabbit epithelial cells (6, 10, 14); (ii) a modified tissue culture medium with 20% fetal bovine serum (FBS) and 0.63 mM dithiothreitol (DTT) to reduce oxygen toxicity (2,6,8,9,12); (iii) a small quantity (1/30th of the total medium volume) of infected testes extract ( 6) and (iv) incubation at 33°C under a microaerobic atmosphere containing 1.5% oxygen (1, 3,6,12,13). Because of the importance of this finding for future T. pallidum research and past failures in repeating reported cultivations, the techniques of Fieldsteel et al were duplicated in an attempt to independently corroborate their results.…”

The applicability of redox-indicator dyes in strongly reduced media; their effect on the human fecal flora

“…In low concentrations DTT appeared to be nontoxic to various rumen bacteria [3] and Treponema pallidum [12,13]. In low concentrations DTT appeared to be nontoxic to various rumen bacteria [3] and Treponema pallidum [12,13].…”

Transfusion Syphilis, Survival of Treponema pallidum in Donor Blood

“…In the latter experiments the percentages of motile [Chalmers and Taylor-Robinson, 1979 ;Cover et ah, 1982 ;Steiner et ah, 1981] and virulent [Steiner et ah, 1981] treponemes show a gradual decrease on prolonged in vitro storage. It seems reasonable to expect a similar decay of virulent treponemes in arti ficially infected stored donor blood.…”