DH5alphas are growing slowly.

Patrick F.H. Lai pfhlai at LOOKSMART.COM
Fri Aug 7 21:20:05 EST 1998

---- Begin Original Message ----
Hello all, 
=09      I have a rather strange problem. I have some competent
DH5a that I made and transformed with a number of plasmids.
The majority of the plasmids (alll amp resistant) grew up on
amp plates o/n at 37oC. SOme plasmids however (PRK plasmid with which
I am not familiar) did not grow up o/n. I left these plates in a furthe=
24 hours at 37oC and lo and behold colonies were visible (non
being visible on the cells only plate). Has this happened to anyone bef=
or does anyone think they can explain it? If so I would be delighted to=
hear from them. I have never witnessed this before and am at a loss.
Thanks in adance,
=09=09=09=09=09Gary Morley
=09=09=09=09=09g.morley at ucl.ac.uk

--- End Original Message ----

Dear Dr. Gary,

My experience has been that late showing colonies do not carry the 
vector and do not survive in minicultures containing antibiotics.
I assume the antibiotics in the agar plates 'dies' in 37 deg. C slowly
and untransformed bacteria grows.

What are you cloning ?
is the insert a gene that slows down bacterial growth ?
Just curious.....

Hope this is useful info.   :-)

Patrick F.H. Lai  < PFHLai at looksmart.com >
Graduate Student
University of Toronto
Toronto, Ontario, Canada

LookSmart =85 or keep looking.

More information about the Methods mailing list