Observations onTetrahymena pyriformis relating to the Pasteur effect

✍ Scribed by Warnock, L. G. ;Van Eys, J.

• Publisher: Wiley (John Wiley & Sons)
• Year: 1963
• Tongue: English
• Weight: 782 KB
• Volume: 61
• Category: Article
• ISSN: 0095-9898
• DOI: 10.1002/jcp.1030610312

✦ Synopsis

There are many theories regarding the mechanism of the Pasteur effect, all of which have experimental support (cf. Aisenberg, '61; van Eys, '61). A large number of these postulates have as their focal point the levels of the adenine nucleotide-inorganic phosphate metabolites. To help ascertain the validity of these various theories of the Pasteur effect manipulations of the levels of these metabolites in vivo would be of great value. It occurred to us that a motile cell expends a good portion of its energy derived from food for the purpose of locomotion. Hence, interference with motility would alter the requirement for ATP and therefore would tend to impose an adjustment on energy metabolism. Such a system had to f u U several criteria before it would be practical. First, a metabolically well defined organism need to be used. The ciliated protozoan Tetrahymena pyrifannis appeared ideal since it can be readily grown in axenic cultures in quantity. Secondly, to make the results generally applicable no qualitative abnormalities in the pathways of energy metabolism should exist on the organism. On investigation this appeared to be so for Tetrahymena (Warnock and van Eys, '62). Thirdly, the organism should exhibit a strong Pasteur effect. This is the case in Tetrahymena which exhibit an absolute Pasteur effect (Warnock and van Eys, '62). In addition, some evidence for a direct link between ATP levels and motility was published recently (Burnasheva and Efremenko, '62).

Once the organism was selected a search was made for motility inhibitors. To be useful for the present purpose they had to: ( a ) inhibit ciliary ATPase specifically or inhibit the motility impulse specifically, and (b) their action must be freely reversible and non-lethal even for reason-