The goal of lab today was to created the YPD media for our yeast cells to grown and thrive on. YPD is a nutrient rich media that can be used in liquid form or used with agar.
The protocol for to create one liter of YPD for the whole class consists of:
Dextrose – 20g (Simple sugar; used as energy source for cell division and respiration)
Peptone – 20g (Short amino acid proteins; used for nutrition)
Yeast extract – 10g (The cell contests of Yeast; used for nutrition)
Distilled water – Filled to 1L
This YPD was combined with 2 grams of agar and then put into an autoclave for sterilization. An autoclave is a machine that puts a sample under high pressure and heat to sterilize it.
A serial dilution in a well plate of our SAK1 deficient yeast culture was conducted 11 times with a 1:1 dilution for each time. A serial dilution is a series compounding dilutions (each subsequent dilution is taken from the dilution before). This allows for an exponential increase in dilution over each time.
The serial dilution was put into a spectrophotometer to find the concentration of yeast per each of the dilutions. A spectrophotometer is a device that calculates the transmittance of light through a medium which can therefore be used to calculate the concentration of the substance in the medium. The concentrations resulted as follows: