Bacterial Chromosomes and PFGE
bgm at ukc.ac.uk
Fri Sep 2 07:49:43 EST 1994
lanoilb at ava.bcc.orst.edu (Brian_D Lanoil) reported that
I am using a five step running system which separates DNA
molecules in the size range from approximately 350 kb to 5 Mb. My
problem: when I run E. coli on the gel as a control, I see multiple
bands. Since E. coli has only one chromosome and this particular strain
has no plasmids, I am at a loss to explain what the extra bands are.
There is one band which runs at the correct size of ~4.5 Mb, but all of
the others are _larger_.
An answer to this maybe:
You maybe seeing the chromosomes sticking together in dimers etc, this is most
likely. Alternativly these bands maybe due to incomplete rounds of replication.
Hope this helps.
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