Yeast and cholesterol - How to differentiate between high-cholesterol and low-cholesterol conditions (Jun/18/2006 )

Hi All

I would like to differentiate between a yeast (S. cerevisiae) strain with high-cholesterol content and a yeast strain with low cholesterol content.

Specifically, my aim is to screen for mutants with low cholesterol content and I am looking for an easy way to do that.

Thanks

Eran

I think there are two approaches. First, molecular biology. If you have access to PCR maybe you could identify a marker from each of your sach strains.

Second, and maybe easier is a biochemical approach, culture the yeast and analyse for cholesterol. There are straightforward spectrophotometric assays for chol. The Trinder reaction uses chlorophenol and H202 and you measure light absorbance. I think this is easy to set up in 75ml test tubes but probably could be done in 96 well plate format if you have many samples. There again, I wonder if you could adapt the protocol and use it directly in the culture. I don't know about toxicity to yeats at the concs you'd use, though.

Let me know if you want me to dig out the details. I'm at home just now but it'd be easy for me in the lab on Monday.