Vibrio vulnificus, a septicemia-causing pathogenic bacterium, acquires resistance against various stresses and expresses virulence factors via an rpoS gene product. In this study, we investigated the transcriptional characteristics of this global regulator. Two distinct transcriptional initiation sites for the rpoS gene, the proximal promoter (P(p)) and the distal promoter (P(d)), were defined ...

Four recombinant mini-Tn5 transposons are described which contain outward-facing Pm, Pu or Psal promoters from the catabolic plasmids TOL and NAH of Pseudomonas putida, along with their cognate wild-type regulatory genes (xylS, xylR, nahR) or mutant varieties (xylS2). Transcription from such promoters is activated when the host bacteria encounters certain aromatic compounds, such as alkyl- and ...

The reporter genes are widely used in promotertrapping vectors for easy and rapid identifi cation of the putative promoter sequences in cloned DNA fragments and in some cases to measure the promoter strength. In this aim, the reporter genes such as a gfp gene from Aequorea victoria encoding Green Fluorescent Protein (Miller et al., 2000; Pothier et al., 2007; Rasko et al., 2007), a lacZ gene en...

The fish pathogen Aeromonas salmonicida was chromosomally marked with genes encoding bacterial luciferase, luxAB, isolated from Vibrio fischeri, resulting in constitutive luciferase production. During exponential growth in liquid batch culture, luminescence was directly proportional to biomass concentration, and luminometry provided a lower detection limit of approximately 10(sup3) cells ml(sup...

Actinobacillus pleuropneumoniae, the etiological agent of porcine pleuropneumonia, is able to survive on respiratory epithelia, in tonsils, and in the anaerobic environment of encapsulated sequesters. It was previously demonstrated that a deletion of the anaerobic dimethyl sulfoxide reductase gene (dmsA) results in attenuation in acute disease (N. Baltes, S. Kyaw, I. Hennig-Pauka, and G. F. Ger...

Genetically constructed microbial biosensors for measuring organic pollutants are mostly applied in aqueous samples. Unfortunately, the detection limit of most biosensors is insufficient to detect pollutants at low but environmentally relevant concentrations. However, organic pollutants with low levels of water solubility often have significant gas-water partitioning coefficients, which in prin...