Epitope-Tagged Autotransporters as Single-Cell Reporters for Gene Expression by a Salmonella Typhimurium wbaP Mutant.

Epitope-Tagged Autotransporters as Single-Cell Reporters for Gene Expression by a Salmonella Typhimurium wbaP Mutant.

Blog Article

Phenotypic diversity is an important trait of bacterial populations and can enhance fitness of the existing genotype in a given environment.To characterize different subpopulations, several studies have analyzed differential gene expression using fluorescent reporters.These studies visualized either single or multiple genes within single cells using different fluorescent proteins.However, variable maturation and folding kinetics of different fluorophores complicate the study of dynamics of gene expression.Here, we present a proof-of-principle study for an alternative gene expression system in a wbaP mutant of Salmonella Typhimurium (S.

Tm) lacking the O-sidechain of the lipopolysaccharide.We employed the hemagglutinin (HA)-tagged inverse autotransporter invasin (invAHA) as a transcriptional reporter for the expression wd ultrastar dc hc530 of the type three secretion system 1 (T1) in S.Tm.Using a two-reporter approach with GFP and the ranchy doodle InvAHA in single cells, we verify that this reporter system can be used for T1 gene expression analysis, at least in strains lacking the O-antigen (wbaP), which are permissive for detection of the surface-exposed HA-epitope.When we placed the two reporters gfp and invAHA under the control of either one or two different promoters of the T1 regulon, we were able to show correlative expression of both reporters.

We conclude that the invAHA reporter system is a suitable tool to analyze T1gene expression in S.Tm and propose its applicability as molecular tool for gene expression studies within single cells.