Enzymatic assay for the neo enzyme?

[Stephen Klautky]

        I have plasmids containing the neomycin resistance gene.  They
have been used to make stable cell lines that are resistant to G418.
But now I would like to determine the relative transcriptional efficiency
of the promoters when the plasmids are transiently transfected.  The
simplest way might be to use an enzymatic assay to *quantitate* neo activity
as one does for CAT or beta-gal.

        Does anyone know of a way to easily assay activity of the neo
gene in cell extracts?  Any paper or company reference would be helpful.

        Thanks.

        ---Steve---

Internet: KLAUTKY at VAXA.WEEG.UIOWA.EDU