recombinant protein - does GST affect the function? (Dec/26/2006 )

I´m planning to buy a recombinant protein that I will add to my cell cultures. There´s a company who sells it, but it is the full-length recombinant protein GST tagged. Because of the GST, the protein has a greater weight (20 kDa more) and I wonder if this difference will affect the protein and its function when I add it to the culture.
Thanks

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any chance of removing the gst?

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I don´t know how to remove it.
Should I ask the company if they can remove it?

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Most probably it has a recognition sequence for removal with thrombin or factor x, maybe should contact the cpmpany

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Thanks tertu!

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the GST tag is likely used to enrich from overexpression system; if there is no documentation on the effect of the tag on the function of the protein, you have to check with an untagged version; do it before a referee evaluates your manuscript

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So I should not believe the company if they tell me the gst won´t affect the function... I should check it myself I haven´t seen anything about this in the literature although I´ll check again
So this means that I will have to buy double amount of protein (veeery expensive): one to remove the gst and the other without removing it...
thanks kosmodrom, I like your new avatar

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If the protien is very expensive, have u looked in to making the protein urself. Also attaching any tag (small or big) to a protien may/maynot alter its function. It depends on the tag and on the protein. One can never know till both forms r tested.

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in the datasheet of the recombinant protein says that it can be used for these purposes: ELISA, WB, Antibody Production, Assay Development, Protein Array.
What does "assay development" mean? what kind of assays do they want to mean?
thanks

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to "assay" is to determine how much of something is present. assay development is to devise a method to make such a determination.

the recombinant protein could be used: as a standard for an assay; as the displaced species in an immunodisplacement assay; if it is an enzyme then it could be used to find out how much of its substrate is present; if it is a substrate for an enzyme then it could be used to determine how much of that enzyme is present.

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