The phenazine pigments pyocyanin and 1-hydroxyphenazine were resolved by high-pressure liquid chromatography from the sputum sol phase from 9 of 13 patients with cystic fibrosis or bronchiectasis colonized by Pseudomonas aeruginosa. The concentrations measured were each sufficient to inhibit ciliary beating in vitro and contributed a significant proportion of sol phase toxicity for respiratory ...

UNLABELLED Studies describing the use of essential oil constituents as antimicrobial agents have steadily increased; however, some phyto-constituents are often overlooked due to unfavourable minimum inhibitory concentration (MIC) values. Virulence depends on transcriptional factors which are regulated by cell-to-cell communication called quorum sensing (QS). This study was undertaken to evaluat...

Background Sinusitis affects significant percentage of population causing considerable long term morbidity. P.aeruginosa is responsible for about 13% of the sinusitis cases. Pseudomonas produces hemolysin, rhamnolipid, a membrane glycolipid, secretory pigments like pyocyanin and 1hydrophenazine which can reduce ciliary beating and mucociliary clearance. Alginate functions as an adhesion, thereb...

Background: Pseudomonas aeruginosa, a multidrug-resistant Gram-negative bacterium, produces pyocyanin, virulence factor associated with antibiotic tolerance. High concentrations of royal jelly have an antibacterial effect, which may potentially overcome resistance. However, in some cases, tolerance can occur due to prolonged stress low-dose a...

The thiazolidinone ring is found in compounds that have widespan biology activity and there mechanism-based evidence bearing this moiety inhibit P. aeruginosa PhzS (PaPzhS), a key enzyme the biosynthesis of virulence factor named pyocyanin. Ten novel derivatives were synthesised screened against PaPhzS, using two orthogonal assays. biological results provided by these 28 other compounds, whose ...

THE PRINCIPAL CONCLUSIONS THAT SEEM TO ME JUSTIFIED ARE AS FOLLOWS: 1. The fluorescent pigment formed by some varieties of B. pyocyaneus is produced under conditions identical with those governing the production of the pigment by other "fluorescent bacteria." 2. The production of pyocyanin is not dependent upon the presence of either phosphate or sulfate in the culture medium. It is formed in n...

In Pseudomonas aeruginosa, the PA4204 gene encodes a protein with a signal peptide and a COG2706 domain of the type present in 3-carboxy-cis,cis-muconate lactonizing enzymes. A molecular model based on the structure of the Escherichia coli YbhE phosphogluconate lactonizing enzyme shows that the enzyme has a beta-propeller ('doughnut') structure and a central active site comprising one histidine...

Pseudomonas putida strains are being developed as microbial production hosts for production of a range of amphiphilic and hydrophobic biochemicals. P. putida's obligate aerobic growth thereby can be an economical and technical challenge because it requires constant rigorous aeration and often causes reactor foaming. Here, we engineered a strain of P. putida KT2440 that can produce phenazine red...

Cystic fibrosis (CF) airways harbour complex and dynamic polymicrobial communities that include many oral bacteria. Despite increased knowledge of CF airway microbiomes the interaction between established CF pathogens and other resident microbes and resulting impact on disease progression is poorly understood. Previous studies have demonstrated that oral commensal streptococci of the Anginosus ...