Single-copy green fluorescent protein gene fusions allow accurate measurement of Salmonella gene expression in vitro and during infection of mammalian cells.

ABSTRACT: We developed a reliable and flexible green fluorescent protein (GFP)-based system for measuring gene expression in individual bacterial cells. Until now, most systems have relied upon plasmid-borne gfp gene fusions, risking problems associated with plasmid instability. We show that a recently developed GFP variant, GFP+, is suitable for assessing bacterial gene expression. Various gfp+ transcriptional fusions were constructed and integrated as single copies into the chromosome of Salmonella enterica serovar Typhimurium. A comparison of the expression levels of proU-lacZ and proU-gfp+ fusions showed that GFP+ reported proU activity in individual Salmonella cells as accurately as beta-galactosidase reported activity for entire populations. The single-copy gfp+ fusions were ideal for monitori

SUBMITTER: Hautefort I 

PROVIDER: S-EPMC310007 | biostudies-literature | 2003 Dec

REPOSITORIES: biostudies-literature