Open AccessFluorescence‐based detection of lacZ reporter gene expression in intact and viable bacteria including Mycobacterium species
Author(s) -
Rowland Belinda,
Purkayastha Anjan,
Monserrat Catherine,
Casart Yveth,
Takiff Howard,
McDonough Kathleen A.
Publication year - 1999
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1999.tb08744.x
Subject(s) - bacteria , green fluorescent protein , reporter gene , microbiology and biotechnology , flow cytometry , lac operon , biology , mycobacterium bovis , fluorescein , gene expression , mycobacterium , gene , fluorescence , chemistry , biochemistry , mycobacterium tuberculosis , genetics , medicine , tuberculosis , physics , pathology , quantum mechanics
A variety of fluorescein di‐β‐ D ‐galactopyranoside (FDG)‐based substrates were evaluated for measuring β‐galactosidase expression in bacteria. One substrate, 5‐acetylamino‐FDG (C2FDG), performed well in all bacteria tested, including the slow growing mycobacterium, Mycobacterium bovis BCG. The sensitivity of C2FDG in intact, viable BCG was similar to that of o ‐nitrophenyl‐β‐ D ‐galactopyranoside in cell lysates when used to measure lacZ reporter gene activity. C2FDG was approximately 70‐fold more sensitive than green fluorescent protein (GFP) in BCG when assayed in a fluorescence plate reader, and comparable to GFP when measured by flow cytometry. These assays provide an important new alternative for the rapid measurement of reporter gene expression in viable bacteria.