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Competent cells question: JM101 vs DH5alpha - (Apr/03/2012 )

I've been having difficulty tracking down E. coli JM101 in my lab's freezer inventory. I'm trying to replicate a published experiment that utilizes JM101 as a host for intermediate plasmids (pBluescript + cloned genes + resistance marker), and I'm wondering if I can just use DH5alpha as host to replicate these intermediate plasmids. Are there any issues with doing this?

-Steve Hwang-

I'm guessing it would be easier with DH5a. JM101 has an intact E. coli restriction system, which will reduce transformation efficiency for some constructs. It also is recA+, which may make some constructs less stable. Is this a paper from 1980?


It's a paper from 2003. But thanks for the info!

-Steve Hwang-