Effect of Varying Concentrations of SSP Medium on the Chemotactic Response of Tetrahymena thermophila

Abstract

This study investigated the chemotactic response observed in hunger-induced Tetrahymena thermophila ( T. thermophila ) when exposed to varying concentrations of a chemoattractant. The chemoattractant used was SSP medium, which was then diluted 10-fold and 100-fold. It was predicted that at high concentrations of the chemoattractant, there would be large chemotactic movement, which would then decline as the concentrations of SSP medium become more dilute. To do this, the preparation of T. thermophila focused on placing them in the starvation medium (10 mM Tris-HCl (pH=7.5) to deprive them of nutrients. A 2-chamber assay apparatus was then used to observe the movement of T. thermophila when varying concentrations of SSP medium were introduced. The highest average count of T. thermophila was found allocated in the maximum concentration of SSP medium (166533.3333 +/- 96904.35147 cells/mL), then followed by at a 10-fold concentration (51157.14286 +/- 32565.79838 cells/mL) and finally at a 100-fold dilution (23958.33333 +/- 23047.61828 cells/mL). There was a linear decrease of chemotactic movement as the concentration of SSP medium decreased. After conducting a one-way ANOVA test and a Tukey’s HSD test, the p-value was found to be 0.0882. These tests showed our results to be insignificant, with no relationships between any groups. We concluded that there is no significant relationship between the chemotactic response of T. thermophila and varying concentrations of SSP medium.