[PQ101]

Hey guys,

I was wondering if it would be possible to make a GS-fluorescien conjugate in the following way:

                                                GST
GSH+Fluorescein sodium salt(Sigma) GS-fluorescien conjugate


http://www.sigmaaldrich.com/catalog/product/sial/f6377?lang=en&region=NL

Any advice if this would work and how to go about it would be great!!

[Yggdrasil]

No, the fluorescein you linked to contains no reactive group that will allow it to be conjugated with proteins.  You would want either a fluorescein isothiocyanate (FITC) or NHS-fluorescein derivative.  These reagents will non-specifically label your protein at primary amines (i.e lysine residues and/or the N-terminus).  There are many commercial protein labeling kits available which will provide a protocol for performing the conjugation reaction and purifying the product.

[PQ101]

Thanks very much for your reply!!

Cheers Pete