What is the role of potassium acetate in the alkaline lysis method of plasmid extraction?
Earlier I was thinking its role is to shield plasmid DNA (the same as sodium acetate in genomic DNA extraction). When 100% ethanol is added, it the DNA precipitates and then we remove potassium ions from the pellet using 70% ethanol.
However, I have read that potassium acetate does not have the same function as sodium acetate in genomic DNA isolation but, rather, is a neutralizing agent which helps small plasmid DNA to renature.
I am bit confused about the role of potassium acetate and why sodium acetate cannot be used instead.