UW-Stout/Methanol

Yeast Growth In Methanol

Marissa Steele and Ian Asperheim

Protocol

Materials:

• yeast
• methanol

Equipment

• assay plate
• 30 degree c incubator

Strains of Yeast experiment 3

• By4735 (wild type)
• YEL035c
• YCL002c
• YFL064c
• YGL235w
• YCR100c
• YJL043w
• YPL068c
• YMR090w

We added 80 microliters of each different strand of yeast into the wells and then added 20 microliters of methanol to give a total of 100 microliters in each well with a 20% concentration.

Put the assay plate in a 30 degrees Celsius incubator and shook it at 120 revolutions/ min for

Experiment 1: Concentration Experiment

• 90 microliters of yeast + 10 microliters of methanol: 86 min
• 90 microliters of yeast + 10 microliters of water: 72 min
• 90 microliters of yeast + 5 microliters of methanol + 5 microliters of water: 76 min
• 90 microliters of yeast + 2 microliters of methanol + 8 microliters of water: 73 min
• 90 microliters of yeast + 1 microliter of methanol + 1 microliter of water: 78 min
• mix 9.5 microliters water and .5 microliters of methanol in a separate tube, flick to mix and add to 90 microliters of yeast: 67 min
• mix 9.75 microliters of water and .25 microliters of methanol in a separate tube, flick to mix and add to 90 microliters of yeast: 128 min
• mix 9.88 microliters of water and .125 microliters of methanol in a separate tube, flick to mix and add to 90 microliters of yeast: 87 min
• mix 9.95 microliters of water and .05 microliters of methanol in a separate tube, flick to mix and add to 90 microliters of yeast: 86 min
• mix 9.98 microliters of water and .02 microliters of methanol in a separate tube, flick to mix and add to 90 microliters of yeast: 84 min
• mix 9.99 microliters of water and .01 microliters of methanol in a separate tube, flick to mix and add to 90 microliters of yeast: 92 min
• mix 9.999 microliters of water and .001 microliters of methanol in a separate tube, flick to mix and add to 90 microliters of yeast: 85 min

Results:These results showed us that the methanol didnt have much effect on the yeast at the small concentrations that we used, this still helped us decide to move to larger concentrations and change our independant variable. We used these results to figure out what concentration to use to see the yeast growth in methanol (see protocol at the top)

Experiment 2: Larger Concentrations

since our last experiment didn't put the yeast through enough strain, we moved to larger concentrations of methanol to get more substantial results.

• 50 microliters of yeast + 50 microliters of methanol
• 50 microliters of yeast + 45 microliters of methanol + 5 microliters of water
• 50 microliters of yeast + 40 microliters of methanol + 10 microliters of water
• 50 microliters of yeast + 35 microliters of methanol + 15 microliters of water
• 50 microliters of yeast + 30 microliters of methanol + 20 microliters of water
• 50 microliters of yeast + 25 microliters of methanol + 25 microliters of water
• 50 microliters of yeast + 20 microliters of methanol + 30 microliters of water

Results: The yeast all died and we didnt get any results, this was still helpful as now we know that we need to reduce the concentrations but keep them higher than the first experiment. We decided to do 80 microliters of yeast and 20 microliters of methanol for each well, but do a different strand of yeast for our independent variable.