- the GFP5 protein (encoded by mgfp5-ER) has excitation peaks
with approximately equal maxima at 395nm and 473nm, and has an emission
peak at 507nm. Kirby Siemering did the fluorimetry here, and the
description can be found in last December's Current Biology (Siemering et
al., Mutations that supress the thermosensitivty of green fluorescent
protein. Current Biology 6:1653-1663, 1996).
Chlorophyll has a broad excitation spectrum, but the emission is red
and can be readily filtered from green fluorescence.
Hope that helps, Jim Haseloff.
> I want to transform Nicotiana pumbaginifola protoplasts with m-gfp-5ER.
> Has any one transformed m-gfp5-ER in Nicotiana? Is m-GFP5-ER stable
> enough for the fluorometric estimation in extracts prepared from the
> protoplasts or do I need to quantitate gfp in intact protoplasts. For a
> fluorometric assay either in intact protoplasts or in the protoplast
> extracts how can I avoid interference from chloroplasts? m-gfp5-ER has
> two excitation peaks at 400 and 473 nm and its emission peak is around
> 510nm (I would be grateful if someone tells me how much is it exactly).
> Please e-mail me to
>Ranjan.Swarup at ens-lyon.fr