(none)

[Susan C. Trapp]

yeast transformations







I am a graduate student who is unfamiliar with yeast transformation

systems.  I am attempting to express a cDNA from filamentous fungus

{fusarium} in yeast {S. Cerevisiae}. I need some information on

yeast transformations.  I have tried the electroporation method

described by Becker & Guarente 1991 Methods in Enzymology, Vol. 194.

My transformations efficiency was low using this method on a medium

containing SD - uracil. We used a Biorad Gene Pulser with their

recommended settings.



I am about to attempt a LiAC method based on Schiestl and Gietz (1989)

Curr. Gen., 16,339, and Hill, Donald, Griffiths,(1991) Nuc Acids Res.,

19, 5791.  Can anyone recommend improvements over or on these methods

for better transformation efficiency?



I also tried using frozen -80 C yeast competant cells (INVSC1) prepared

as described by Becker & Guarente in 1M sorbitol and found that it cause

arching during electroporation.  Does anyone have an explanation and

protocol for preparing yeast competant cells that can be stored at -80 C.
 
Susan Trapp
email waldopep at wam.umd.edu