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IPTG induction and addition of glucose - (Sep/10/2007 )

dear all,

I am wondering if addition of glucose as an excesive carbon source into the medium will affect the expression of the T7 promoter induced by IPTG? rolleyes.gif

thanks in advance

-joerene-

QUOTE (joerene @ Sep 11 2007, 04:40 PM)
dear all,

I am wondering if addition of glucose as an excesive carbon source into the medium will affect the expression of the T7 promoter induced by IPTG? rolleyes.gif

thanks in advance

How much did you add? Unless it's very very high, I think that the IPTG is a strong enough inducer of expression that you'll still get good induction of your protein.

-swanny-

The final concentration of glucose is 5% and i culture it in 3mL of LB.

Thanks smile.gif

-joerene-

I think that the IPTG induced LacUV5 promoter, from which the T7 polymerase is expressed, doesn't have a CAP binding site, so it is not subject to catabolite repression by glucose. So the answer would be that glucose will not inhibit the expression.

-bitesizebio guy-