E. coli strain request

[Barbara MacGregor]

Hello,

I can't recommend a particular strain, but you can search for strains  
by genotype at CGSC:

http://cgsc2.biology.yale.edu/index.php

Sorry if you've already looked there!

Barbara MacGregor

>
>
> We wish to use lactose (and not IPTG) to induce expression of genes  
> cloned
> into pGEX vectors (under control of the lac operator) for large scale
> protein purification.  To utilise lactose, as opposed to IPTG,  
> requires an
> E. coli strain that has a wild type lac operon, wild type gal operon  
> and
> ideally ompT and lon defective to prevent protease degradation of the
> expressed gene.
>
> Anyone out there have such an E.coli strain or suggestions?  Most lab
> strains appear to be mutated in the lac and/or gal operons.
>
> Mick Jones