A rapid and simple chemiluminescent assay for Escherichia coli beta-galactosidase.
We describe a chemiluminescent assay for E. coli beta-galactosidase using Lumi-Gal 530, a commercial formulation containing a stable phenylgalactose-substituted dioxetane as the substrate. Removal of the galactose moiety leads to the generation of an unstable dioxetane which decomposes to provide the observed chemiluminescence which is measured with a luminometer. Advantages of the assay are that it is simple, inexpensive and has 20-fold greater sensitivity than the standard spectrophotometric assay. Additional advantages are that the dioxetane is quite stable in the commercial formulation, and beta-galactosidase functions efficiently and is not degraded during the course of an assay. As luminometers are becoming commonplace in molecular biology laboratories, this assay provides a preferable alternative to the spectrophotometric assay.
Beale
E G
EG
Department of Cell Biology and Anatomy, Texas Tech University Health Sciences Center Lubbock 79430.
Deeb
E A
EA
Handley
R S
RS
Akhavan-Tafti
H
H
Schaap
A P
AP
D001709:Biotechnology; D004926:Escherichia coli / Q000201:enzymology; D005069:Evaluation Studies as Topic; D008163:Luminescent Measurements; D013053:Spectrophotometry; D001616:beta-Galactosidase / Q000032:analysis*
D001616:beta-Galactosidase