Pyocyanin has recently emerged as an important virulence factor produced by Pseudomonas aeruginosa. The redox-active tricyclic zwitterion has been shown to have a number of potential effects on various organ systems in vitro, including the respiratory, cardiovascular, urological, and central nervous systems. It has been shown that a large number of the effects to these systems are via the formation of reactive oxygen species. The limitations of studies are, to date, focused on the localized effect of the release of pyocyanin (PCN). It has been postulated that, given its chemical properties, PCN is able to readily cross biological membranes, however studies have yet to be undertaken to evaluate this effect. This review highlights the possible manifestations of PCN exposure; however, most studies to date are in vitro. Further high quality in vivo studies are needed to fully assess the physiological manifestations of PCN exposure on the various body systems.

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Cellular Effects of Pyocyanin, a Secreted Virulence Factor of Pseudomonas aeruginosa.

In vitro activity of ceftolozane/tazobactam against clinical isolates of Pseudomonas aeruginosa in the planktonic and biofilm states.

With the development of invasive medical procedures, an increasing number of healthcare-associated infective endocarditis cases have been reported. In particular, non-nosocomial healthcare-associated infective endocarditis in outpatients with recent medical intervention has been increasingly identified. A 66-year-old man with diabetes mellitus and a recent history of intermittent urethral self-catheterization was admitted due to a high fever. Repeated blood cultures identified Pseudomonas aeruginosa, and transesophageal echocardiography uncovered a new-onset severe aortic regurgitation along with a vegetative valvular structure. The patient underwent emergency aortic valve replacement surgery and was successfully treated with 6 weeks of high-dose meropenem and tobramycin. Historically, most cases of P. aeruginosa endocarditis have occurred in the right side of the heart and in outpatients with a history of intravenous drug abuse. In the case presented, the repeated manipulations of the urethra may have triggered the infection. Our literature review for left-sided P. aeruginosa endocarditis showed that non-nosocomial infection accounted for nearly half of the cases and resulted in fatal outcomes as often as nosocomial cases. A combination therapy with anti-pseudomonal beta-lactams or carbapenems and aminoglycosides may be the preferable treatment. Medical treatment alone may be effective, and surgical treatment should be carefully considered. We presented a rare case of native aortic valve endocarditis caused by P. aeruginosa. This case illustrates the importance of identifying the causative pathogen(s), especially for outpatients with a recent history of medical procedures.

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Non-nosocomial healthcare-associated left-sided Pseudomonas aeruginosa endocarditis: a case report and literature review.



P.aeruginosa, has been frequently connected to immune-compromised individuals. Dynamic electrochemical metabolite assists in the creation of biofilms, the production of genes, and the maintenance of bacterial cells. The bacteria produce several phenazine derivatives, as well as the blue-green pigment pyocyanin, which works as a signalling molecule in quorum signalling and virulence factors.



This review paper intends to give information on the compound's history, virulence mechanism, current biological horizon opened, as well as antagonism and bio-control actions in other bacteria. Current industrial trends and the prospects of pyocyanin-based development were also analysed.



A bibliographic search of scientific literature published up to 2020 was conducted using scientific databases and search engines. Pyocyanin, phenazine, Pseudomonas, virulence, quorum signalling, health, in vivo, and clinical investigations were among the keywords used in various combinations. The data were retrieved independently from eligible papers using the usual data extraction approach.



Due to pyocyanin's antibacterial properties, the pharmaceutical industry is predicted to grow faster than other businesses. P.aeruginosa which has had its respiratory chain altered by protonated 3,5-dichlorophenol in water can be used as a biosensor. Cellular systems exposed to the chemical experience increased oxidative stress, which leads to gradual apoptosis. Pyocyanin is engaged in bacterial signalling processes, influencing colony shape and alarming innate immune cells.



Focused research on the virulence factor is required, as the specific contribution remains unknown. The link between biological and therapeutic features needed well description to determine the precise action mechanism(s) to design novel medications.


Pyocyanin is the Microbial blue-green Pigment: A review on its History, Virulence, and Therapeutic Use

Previously, endocarditis caused by Pseudomonas aeruginosa mostly involved right-sided valvular infection and generally carried a good prognosis. Recently, changes have been observed in the occurrence and clinical presentation of pseudomonal endocarditis, with increasing incidence of nosocomial infections and involvement of the aortic and mitral valves. Still, pseudomonal left-sided endocarditis is rare, but is frequently associated with complications and high mortality rates. A case of a high-risk patient with coronary artery disease and left-ventricular dysfunction, successfully treated for pseudomonal mitral valve endocarditis complicated by splenic abscess formation, is presented here.

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Momcilo Jovanovic

Papers

Mitral valve endocarditis caused by Pseudomonas aeruginosa: a case report