No use, distribution or reproduction is permitted which does not comply with these terms. This article has been cited by other articles in PMC. Abstract Phialophora verrucosa is a dematiaceous fungus able to cause chromoblastomycosis, phaeohyphomycosis and mycetoma. All these fungal diseases are extremely difficult to treat and often refractory to the current therapeutic approaches. Therefore, there is an urgent necessity to develop new antifungal agents to combat these mycoses.
Cell morphology changes inflicted by phendione and its metal-based derivatives was corroborated by scanning electron microscopy, which revealed irreversible ultrastructural changes like surface invaginations, cell disruption and shrinkages. To different degrees, all of the test compounds were able to disturb the P. Keywords: Phialophora verrucosa, 1,phenanthroline-5,6-dione, metal-based drugs, antifungal activity, chromoblastomycosis Introduction Phialophora verrucosa is a melanized pathogenic fungus associated with a wide range of neglected diseases including phaeohyphomycosis, mycetoma, keratitis, endophthalmitis, osteomyelitis and endocarditis Turiansky et al.
However, this fungus is especially known to cause chromoblastomycosis CBM , which is a chronic, progressive disease affecting the cutaneous and subcutaneous tissues Torres-Guerrero et al.
Clinically, CBM is characterized by pseudoepitheliomatous hyperplasia with epidermal microabscesses and dermal granuloma. This disease is most prevalent among individuals with outdoor occupations, such as farmers, gardeners and agricultural laborers.
This risk group is usually exposed to soil, wood and rotting vegetation, which are the ubiquitous natural habitats of the fungal etiologic agents of CBM Torres-Guerrero et al. CBM usually occurs through trauma or skin penetration of fungal propagules in individuals lacking adequate protective footwear and clothing Torres-Guerrero et al. Due to the chronic nature and the well-known multidrug-resistance profile, it is very difficult to treat patients with CBM using currently available therapies Queiroz-Telles and Santos, Prolonged treatment and disease relapsed are huge concerns, and antifungal therapies especially for Phialophora infections have generally been disappointing Gao et al.
For these reasons, new antifungal agents should be studied in order to find out alternative therapeutic ways to treat CBM and other infections caused by P.
In the last years, metal-based drugs have been a subject of great interest due to their therapeutic values and pharmacological applications Zhang and Lippard, ; Warra, ; Viganor et al. Phendione has a structure similar to 1,phenanthroline with the addition of two carbonyl groups attached at positions 5 and 6. The bifunctional character of phendione made it an extremely versatile ligand, with special reactivity arising from its quinonoid and diiminic sites Calderazzo et al.
The quinonoid functionality of phendione confers redox capability, whilst the juxtaposition is two N atoms make it ideally suited to chelating transition metal ions Calderazzo et al. Phendione, both in its metal-free state and when coordinated to metal ions, is considered to have many interesting biological properties, such as anticancer and antimicrobial actions McCann et al.
Metal-free phendione exerts its antimicrobial effect in several ways, such as disturbing the microorganism's crucial metal metabolism as well as interfering in its metal ion acquisition and its bioavailability for essential reactions e. Protease inhibition is also a prime cellular target of this class of ligand and its associated metal complexes Kellett et al.
Microorganism and growth condition Phialophora verrucosa FMC. Conidia were obtained after gauze filtration followed by centrifugation 4. Then, conidia were washed three times in 0. All the experiments with P. Effects of test compounds on P. Safakath, Reji Philip.
Synthesis, characterization and third-order nonlinear optical studies of copper complexes containing 1,phenanthroline-5,6-dione and triphenylphosphine ligands. Synthetic Metals , , Journal of the Korean Electrochemical Society ,,, Zhiqiang Gao, Yuan Hong Yu.
Biosensors and Bioelectronics , 22, Transition metal derivatives of 1,phenanthroline-5,6-dione: Controlled growth of coordination polynuclear derivatives.
Inorganica Chimica Acta , , Kang Shi, Kwok-Keung Shiu. Adsorption of copper and lead species at electrochemically activated glassy carbon electrodes. Electrochimica Acta , 51, Adsorption of some quinone derivatives at electrochemically activated glassy carbon electrodes. Peng Wang, Guo-Yi Zhu.
Chinese Journal of Chemistry , 20, Fernando Garay. Adsorptive square wave voltammetry of metal complexes. Effect of ligand concentration. Randolph P. Thummel, Charles M. Recent advances in the synthesis and chemistry of 1,phenanthroline derivatives. Analytica Chimica Acta , ,The use of freshly cleaved basal plane pyrolytic graphite electrodes allowed the surface coordination chemistry and electrochemistry of pdon, pdol, and their complexes to be inspected in more synthesis than in previous studies. DOI: All these fungal diseases are extremely difficult to Analytical problem solving skills quiz and often refractory to the current therapeutic approaches Mark T. One side is claiming that unbridled population increase is energy so much strain on the financial and food the next five years, and what will have to the book or of the person who gave it.
Protease inhibition is also a prime cellular target of this class of ligand and its associated metal complexes Kellett et al. Transition metal derivatives of 1,phenanthroline-5,6-dione: Controlled growth of coordination polynuclear derivatives. Phendione has a structure similar to 1,phenanthroline with the addition of two carbonyl groups attached at positions 5 and 6. Serial dilution was made following CLSI guidelines in order to obtain final concentrations ranging from 0. These data corroborate previously published results, which revealed that phendione-based metal complexes had higher antimicrobial activity than metal-free phendione toward different classes of microorganisms McCann et al.
Adsorption of some quinone derivatives at electrochemically activated glassy carbon electrodes. Metal-free phendione exerts its antimicrobial effect in several ways, such as disturbing the microorganism's crucial metal metabolism as well as interfering in its metal ion acquisition and its bioavailability for essential reactions e. Alexander D. Effect of ligand concentration. The adsorbed or precipitated molecular layers can interfere with the continued electroreduction of the more soluble, oxidized precursors from which they are generated.