No GFP in E. coli broth cultures

[Misha Ponomarev]

Hi

I've grown JM105(pGFP) at both room temp and 37C in rich liquid culture
with IPTG overnight.  I never saw any fluorescence by eye.  In the
fluorimeter, the broth actually interferes with the signal, so I resorted
to washing the cells with buffer a few times.  After that I could clearly
see the fluorescence in whole cell suspensions (at approx the density of
stationary phase cells).  Without IPTG I couldn't see anything.  I hope
this helps.

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