Subject: discrimination between lysos. beta-Gal and E.coli beta-Gal ?

From: [email-masked] (Frank Gaunitz)
Date: 21 Oct 93 17:44:29 GMT

am doing transfection experiments in primary cultures from rat liver 
with vectors that carry a lacZ reporter gene. 
Expression levels are determined by a methyl-umbelliferryl assay.
ONPG is not sensitive enough.
Galacto-light doesn't work, because, our extracts kill the enhancer
used in this assay.
My problem now is, that I have very high backround levels of lysosomal
galactosidase activity.
Different pH in the detection reaction does not lead to a proper 
discrimination between lysosomal and transfected (E. coli) activity
of the enzyme.
Does any one have a good idea, how to kill ? the lysosomal activity
or how to enhance E. coli beta-Gal activity.

Frank Gaunitz
Physiologisch-chemisches Institut
Universitaet Tuebingen
Hoppe-Seyler-str. 4
72076 Tuebingen
Germany
+49 07071 293356

e-mail: 	[email-masked]
internet:	134.2.101.11