Very technical question.
From my past experience building libraries in S. cerevisiae, after electroporating yeast with a ligation reaction or with plasmid preps, the cells are incubated in liquid medium (typically overnight) and glycerol stocks are then made from that culture.
Why is this different from electroporation of libraries into E. coli, where typically the electroporated cells are spread on agar media and glycerol stocks subsequently made from loosening the bacterial growth from the agar surface into freezing media ?
Is there any benefit in plating electroporated yeast on agar medium just like with E. coli ?
After transfection your liquid culture will contain a mix of untransfected and transfected cells. Plating allows for selective marker screening and to pick colonies derived from a single transfection event so the resulting population is clonal. With the case of libraries the plasmids will have a variable insert so each colony can be viewed as potentially having a different insert.
The need to plate or not probably has to do with the selection being used in your yeast system. In yeast nutritional auxotrophies are commonly used for selection so untransfected cells starve and die out in the growth media. In bacteria the selection is usually done using antibiotic resistance so resistant cells can protect susceptible ones by degrading the antibiotic in the media. Susceptible cells are not always killed by antibiotic selection so can recover and outcompete transfected cells when antibiotic selection is reduced.
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