Expression problems

Duncan Clark Duncan at
Thu Oct 20 07:55:55 EST 1994

In article: <16OCT199400110598 at>  jwickham at (WICKHAM,JOHN) writes:

> IMHO, cells would express proteins best while they remain in exponential
> growth. My protocol involves inducing expression with IPTG at an optical
> density (595nm) of 0.6, then harvesting after 2 hours. The idea is to insure
> cells are harvested prior to reaching stationary phase. Don't forget that
> individual strains and media will vary in their growth curve (I use TG1 cells
> and LB). You might want to do a growth curve if you plan on making more use of
> your expression system, although OD595 at 0.6 is a good estimate of exponential
> growth.

If I do this I get negligible overexpression. Something appears to be rate
limiting the expression hence the slow build up.

My mind's made up. Don't confuse me with the facts!

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