Zinc is essential for all bacteria, but excess amounts of the metal can have toxic effects. To address this, bacteria have developed tightly regulated zinc uptake systems, such as the ZnuABC zinc transporter which is regulated by the Fur-like zinc uptake regulator (Zur). In Pseudomonas aeruginosa, a Zur protein has yet to be identified experimentally, however, sequence alignment revealed that t...

A mutant, named 11B, hypersusceptible to aminoglycosides, tetracycline, and erythromycin was isolated after Tn501 insertion mutagenesis of Pseudomonas aeruginosa PAO1. Cloning and sequencing experiments showed that 11B was deficient in an, at that time, unknown active efflux system that contains homologs of MexAB. This locus also contained a putative regulatory gene, mexZ, transcribed divergent...

The genome of Pseudomonas aeruginosa PAO1 contains three type VI secretion systems (T6SSs) called H1-, H2-, and H3-T6SS. The H1-T6SS secretes three identified toxins that target other bacteria, providing a fitness advantage for P. aeruginosa, and likely contributes to bacterial pathogenesis in chronic infections. However, no specific substrates or defined roles have been described for the two o...

Evidence suggests that the Pseudomonas aeruginosa PAO1 gnyRDBHAL cluster, which is involved in acyclic isoprenoid degradation (A. L. Díaz-Pérez, N. A. Zavala-Hernández, C. Cervantes, and J. Campos-García, Appl. Environ. Microbiol. 70:5102-5110, 2004), corresponds to the liuRABCDE cluster (B. Hoschle, V. Gnau, and D. Jendrossek, Microbiology 151:3649-3656, 2005). A liu (leucine and isovalerate u...

Under conditions of iron limitation, Pseudomonas aeruginosa secretes a high-affinity siderophore pyoverdine to scavenge Fe(III) in the extracellular environment and shuttle it into the cell. Uptake of the pyoverdine-Fe(III) complex is mediated by a specific outer-membrane receptor protein, FpvA (ferripyoverdine receptor). Three P. aeruginosa siderovars can be distinguished, each producing a dif...

In this report we describe experiments to investigate a simple virulence model in which Pseudomonas aeruginosa PAO1 rapidly paralyzes and kills the nematode Caenorhabditis elegans. Our results imply that hydrogen cyanide is the sole or primary toxic factor produced by P. aeruginosa that is responsible for killing of the nematode. Four lines of evidence support this conclusion. First, a transpos...

A commentary on The icmF3 locus is involved in multiple adaptation-and virulence-related characteristics in Pseudomonas aeruginosa PAO1 Pseudomonas aeruginosa is an important pathogen commonly isolated from patients with burns, wounds and cystic fibrosis (Lyczak et al., 2000; Gellatly and Hancock, 2013). The P. aeruginosa strain PAO1 was originally reported as a wound isolate from a patient in ...

The steady-state response of Pseudomonas aeruginosa to the oxidative-stress-generating agent hydrogen peroxide was analyzed by PAO1 transcriptome profiling. In total, 694, 411, and 237 genes were upregulated and 668, 576, and 468 genes were downregulated in P. aeruginosa strains TB, 892, and PAO1, respectively. The expression profiles of the two variants of the TB clone were significantly more ...

Pseudomonas aeruginosa PAO1 utilizes proline as the sole source of carbon and nitrogen via a bifunctional enzyme (the putA gene product) that has both proline dehydrogenase (EC 1.5.99.8) and pyrroline 5-carboxylate dehydrogenase (EC 1.5.1.12) activities. We characterized the pruR-putAP loci encoding the proline catabolic system of this strain. In contrast to the putA and putP (encoding proline ...

Multiple-drug-resistant mutants were isolated from Pseudomonas aeruginosa PAO1 on agar plates containing ofloxacin and cefsulodin. These mutants were four to eight times more resistant to meropenem, cephems, carbenicillin, quinolones, tetracycline, and chloramphenicol than the parent strain was. In contrast, these mutants showed no significant changes in their susceptibilities to all carbapenem...