Measuring intracellular calcium concenrations in Pichia pastoris

Pichia pastoris, a methylotrophic yeast, is used for heterologous protein expression. Calcium is an important second messenger in signal transduction. Little research has been performed to analyze calcium homeostasis in P. pastoris. In our research, we compared the growth rate of P. pastoris under different calcium concentrations. The growth rate was higher with higher concentration of calcium. We then tested the ability of different ions (calcium, potassium, and sodium) to increase the intracellular calcium concentration of P. pastoris. Only calcium was able to increase intracellular calcium concentration. Knowing that calcium has an effect on cell growth and intracellular calcium concentrations, we can possibly increase protein expression and secretion from Pichia Pastoris by altering calcium concentrations