GST-fusion yield 50mg/0.5 lt culture?

Didier Thomas dmthomas at
Wed Oct 9 23:57:29 EST 1996

In article <vurquidi.1195365225A at>, vurquidi at
(Virginia Urquidi) wrote:

> I'd appreciate the comments of those with experience in the subject.
> The protein yields for GST fusion proteins according to the Pharmacia
> purification protocols are the following:
>                         50mg    10mg    1mg     50ug
> Culture volume          20lt    4lt     20ml    1ml
> Someone has just said to me that he produced 50mg of pure protein out of
> half a liter culture. Is that feasible?
> Also, the 0.5 lt culture was inoculated with the total of the 50ml overnight
> culture (instead of the recommended 1:100 dilution). Is this sensible?  
> Is the OD600 between 0.5 and 2 adequate for induction? What would happen if
> you induce at much higher cell densities?
> Thanks in advance for your comments

never expect this kind of yield. 50 mg of gst fusion protein per .5 l of
culture is a joke !!

Induction should be started on an exponentially growing culture (OD ~ .5
is OK) and should last at least 3 hrs.

Temperature : 30 or 37 C depending on your protein.

Keep in mind that the yield depends also on the size of your fusion
protein. The longer the less you get in a bacterial system.

Good luck.


Didier Thomas
University of California, Irvine
College of Medicine
Dept. of Biological Chemistry
Med. Sci. I, Room D214
Irvine, CA 92717

More information about the Methods mailing list