Science Buddies: "Ask an Expert"

Please and thank you for any help in advance!!!

I'm doing an experiment to test if yeast cells that replicate more also die faster due to the Hayflick limit.I have been growing my yeast for 3 days now, they are a lawn, in three separate conditions; 32C, 24C and 3C.

I want to use Trypan Blue to dye for the cells that have died. But, I am not sure how to go about this. I am growing my yeast of an agar plate. I have standard Trypan blue to use. Should I just scrape a small sample of the yeast off the plates and dye that? My teacher said I will probably needed to make it more dilute first so i will be able to count them.

Basically: How can I use Trypan Blue to dye my yeast cells growing on agar plates and look at them under a microscope?

Hi Lost Science,

Here is an article that outlines a few different methods for identifying dead cells in yeast colonies, including the use of trypan blue. You should be able to find it in a library or download it from the internet. A good resource for finding scientific articles on the internet is scholar.google.com, though sometimes you have to pay for access to full articles. Be sure to properly cite the authors if you use this method.

Title: Simple detection method for distinguishing dead and living yeast colonies
Authors: Judit Kucsera, Kyoko Yarita, Kanji Takeo

Journal of Microbiological Methods
Volume 41, Issue 1, June 2000, Pages 19-21

Hope that helps,
Tricia