Name: Jeff R.
Status: Student
Age: 20s
Location: N/A
Country: N/A
Date: N/A
Question:
When electroporating E. coli
cells, why aren't the bacteria killed by the electrical shock? If they
aren't killed because the voltage isn't high enough, what is the highest
level before the bacteria are killed? Also, how is it that
"shocking" bacteria allows plasmid DNA to enter the cell? Thanks
Replies:
During electroporation the bacteria are not killed
because the shock lasts for miliseconds only. If the
shock lasts longer, the temperature rises too much and
viability decreases (another way of saying that
bacteria are killed). How exactly this makes DNA enter
the cells is unclear. It is thought that the
electrical field 'pulls in' the DNA (a charged
molecule), but this is a plastic visualization of a
process we do not fully understand. More important is
that it works, and it is an efficient way of bringing
DNA (either plasmids or fragments of chromosomal DNA)
into a cell.
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