Mechanisms of the Antifungal Action of Marine Metagenome-Derived Peptide, MMGP1, against Candida albicans

The antimicrobial photodynamic therapy (aPDT) is a promising approach for the control of microbial and especially fungal infections such as mucosal mycosis. TMPyP [5,10,15, 20-tetrakis(1-methylpyridinium-4-yl)-porphyrin tetra p-toluenesulfonate] is an effective photosensitizer (PS) that is commonly used in aPDT. The aim of this study was to examine the localization of TMPyP in Candida albicans before and after irradiation with visible light to get information about the cellular mechanism of antifungal action of the photodynamic process using this PS. Immediately after incubation of C. albicans with TMPyP, fluorescence microscopy revealed an accumulation of the PS in the cell envelope. After irradiation with blue light the complete cell showed red fluorescence, which indicates, that aPDT is leading to a damage in the cell wall with following influx of PS into the cytosol. Incubation of C. albicans with Wheat Germ Agglutinin (WGA) could confirm the cell wall as primary binding site of TMPyP. The finding that the porphyrin accumulates in the fungal cell wall and does not enter the interior of the cell before irradiation makes it unlikely that resistances can emerge upon aPDT. The results of this study may help in further development and modification of PS in order to increase efficacy against fungal infections such as those caused by C. albicans.

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Prothioconazole and Prothioconazole-Desthio Activities against Candida albicans Sterol 14-α-Demethylase

Applied and Environmental Microbiology ◽

10.1128/aem.03246-12 ◽

2012 ◽

Vol 79 (5) ◽

pp. 1639-1645 ◽

Cited By ~ 44

Author(s):

Josie E. Parker ◽

Andrew G. S. Warrilow ◽

Hans J. Cools ◽

Bart A. Fraaije ◽

John A. Lucas ◽

...

Keyword(s):

Candida Albicans ◽

Type Ii ◽

Inhibitor Binding ◽

Binding Properties ◽

Content Type ◽

Azole Antifungals ◽

A Cell ◽

Antifungal Action ◽

Binding Spectra

ABSTRACTProthioconazole is a new triazolinthione fungicide used in agriculture. We have usedCandida albicansCYP51 (CaCYP51) to investigate thein vitroactivity of prothioconazole and to consider the use of such compounds in the medical arena. Treatment ofC. albicanscells with prothioconazole, prothioconazole-desthio, and voriconazole resulted in CYP51 inhibition, as evidenced by the accumulation of 14α-methylated sterol substrates (lanosterol and eburicol) and the depletion of ergosterol. We then compared the inhibitor binding properties of prothioconazole, prothioconazole-desthio, and voriconazole with CaCYP51. We observed that prothioconazole-desthio and voriconazole bind noncompetitively to CaCYP51 in the expected manner of azole antifungals (with type II inhibitors binding to heme as the sixth ligand), while prothioconazole binds competitively and does not exhibit classic inhibitor binding spectra. Inhibition of CaCYP51 activity in a cell-free assay demonstrated that prothioconazole-desthio is active, whereas prothioconazole does not inhibit CYP51 activity. Extracts fromC. albicansgrown in the presence of prothioconazole were found to contain prothioconazole-desthio. We conclude that the antifungal action of prothioconazole can be attributed to prothioconazole-desthio.

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Antifungal action of human cathelicidin fragment (LL13–37) on Candida albicans

Peptides ◽

10.1016/j.peptides.2011.08.018 ◽

2011 ◽

Vol 32 (10) ◽

pp. 1996-2002 ◽

Cited By ~ 36

Author(s):

Jack Ho Wong ◽

Tzi Bun Ng ◽

Anna Legowska ◽

Krzysztof Rolka ◽

Mamie Hui ◽

...

Keyword(s):

Candida Albicans ◽

Antifungal Action

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Oxygen accessibility and iron levels are critical factors for the antifungal action of ciclopirox against Candida albicans

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dki089 ◽

2005 ◽

Vol 55 (5) ◽

pp. 663-673 ◽

Cited By ~ 32

Author(s):

Hans-Christian Sigle ◽

Sascha Thewes ◽

Markus Niewerth ◽

Hans Christian Korting ◽

Monika Schäfer-Korting ◽

...

Keyword(s):

Candida Albicans ◽

Critical Factors ◽

Antifungal Action

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The antifungal action of three South African honeys on Candida albicans

Apidologie ◽

10.1051/apido:2001137 ◽

2001 ◽

Vol 32 (4) ◽

pp. 371-379 ◽

Cited By ~ 30

Author(s):

Frans Theunissen ◽

Sias Grobler ◽

Itzhak Gedalia

Keyword(s):

Candida Albicans ◽

South African ◽

Antifungal Action

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AVALIAÇÃO IN VITRO DA AÇÃO ANTIFÚNGICA DO DIGLUCONATO DE CLORHEXIDINA E NISTATINA NO CONTROLE DO CRESCIMENTO DE Candida albicans

Visão Acadêmica ◽

10.5380/acd.v4i2.535 ◽

2003 ◽

Vol 4 (2) ◽

Author(s):

Nayanna Coutinho De FARIAS ◽

Marilene Magalhães BUFFON ◽

Rafael CINI

Keyword(s):

Candida Albicans ◽

Chlorhexidine Digluconate ◽

Agar Culture ◽

In Vitro Evaluation ◽

Antifungal Properties ◽

Yeast Strains ◽

Antifungal Action ◽

Chlorhexidine Solution

O estudo tem como objetivo avaliar comparativamente as propriedades antifúngicas da nistatina 100.000 UI em relação à solução de digluconato de clorhexidina a 0.2%. A suspensão de C. albicans foi semeada em meio de cultura de BHI com ágar, com cerca de 6mm de espessura distribuídos em placas de petri com escavações de 7mm de diâmetro. Após 10 repetições, obteve-se os resultados de acordo com o halo de inibição formado pela solução. Para o digluconato de clorhexidina o halo de inibição foi de 27mm e para nistatina foi 17mm. Assim, pode-se considerar a clorhexidina 0,2% no estudo in vitro como superior no combate antifúngico das cepas de leveduras em relação à nistatina. IN VITRO EVALUATION OF ANTIFUNGAL ACTION OF CHLORHEXIDINA DIGLUCONATE AND NYSTATIN ON THE GROWING CONTROL OF Candida albicans Abstract The study aim to compare the antifungal properties between 100.000 IU nystatin and 0.2% chlorhexidine digluconate solution. The C. albicans suspension was seeded in a BHI agar culture, with 6mm of thickness distributed in Petri plates with 7mm diameters holes. After 10 repetitions, the results were measured according to the inhibitions halos created by the solution. The chlorhexidine solution inhibition halo was 27mm and the nystatin was 17mm. Therefore, the 0.2% chlorhexidine solution may be considered more effective them nystatin in the antifungal action against yeast strains.

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Novel Bi-Factorial Strategy against Candida albicans Viability Using Carnosic Acid and Propolis: Synergistic Antifungal Action

Microorganisms ◽

10.3390/microorganisms8050749 ◽

2020 ◽

Vol 8 (5) ◽

pp. 749

Author(s):

Alejandra Argüelles ◽

Ruth Sánchez-Fresneda ◽

José P. Guirao-Abad ◽

Cristóbal Belda ◽

José Antonio Lozano ◽

...

Keyword(s):

Candida Albicans ◽

Pathogenic Fungi ◽

Carnosic Acid ◽

Moderate Degree ◽

Drastic Reduction ◽

Fungicidal Action ◽

Natural Extracts ◽

Antifungal Action ◽

High Concentrations

The potential fungicidal action of the natural extracts, carnosic acid (obtained from rosemary) and propolis (from honeybees’ panels) against the highly prevalent yeast Candida albicans, used herein as an archetype of pathogenic fungi, was tested. The separate addition of carnosic acid and propolis on exponential cultures of the standard SC5314 C. albicans strain caused a moderate degree of cell death at relatively high concentrations. However, the combination of both extracts, especially in a 1:4 ratio, induced a potent synergistic pattern, leading to a drastic reduction in cell survival even at much lower concentrations. The result of a mathematical analysis by isobologram was consistent with synergistic action of the combined extracts rather than a merely additive effect. In turn, the capacity of SC5314 cells to form in vitro biofilms was also impaired by the simultaneous presence of both agents, supporting the potential application of carnosic acid and propolis mixtures in the prevention and treatment of clinical infections as an alternative to antibiotics and other antifungal agents endowed with reduced toxic side effects.

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Antifungal mechanism of essential oil from Anethum graveolens seeds against Candida albicans

Journal of Medical Microbiology ◽

10.1099/jmm.0.055467-0 ◽

2013 ◽

Vol 62 (8) ◽

pp. 1175-1183 ◽

Cited By ~ 43

Author(s):

Yuxin Chen ◽

Hong Zeng ◽

Jun Tian ◽

Xiaoquan Ban ◽

Bingxin Ma ◽

...

Keyword(s):

Candida Albicans ◽

Plasma Membrane ◽

Essential Oil ◽

Flow Cytometric Analysis ◽

Ros Production ◽

Anethum Graveolens ◽

Antifungal Mechanism ◽

Ros Accumulation ◽

Ergosterol Synthesis ◽

Antifungal Action

This work studied the antifungal mechanism of dill seed essential oil (DSEO) against Candida albicans. Flow cytometric analysis and inhibition of ergosterol synthesis were performed to clarify the mechanism of action of DSEO on C. albicans. Upon treatment of cells with DSEO, propidium iodide penetrated C. albicans through a lesion in its plasma membrane. DSEO also significantly reduced the amount of ergosterol. These findings indicate that the plasma membrane of C. albicans was damaged by DSEO. The effect of DSEO on the functions of the mitochondria in C. albicans was also studied. We assayed the mitochondrial membrane potential (mtΔψ) using rhodamine 123 and determined the production of mitochondrial dysfunction-induced reactive oxygen species (ROS) via flow cytometry. The effects of the antioxidant l-cysteine (Cys) on DSEO-induced ROS production and the antifungal effect of DSEO on C. albicans were investigated. Exposure to DSEO increased mtΔψ. Dysfunctions in the mitochondria caused ROS accumulation in C. albicans. This increase in the level of ROS production and DSEO-induced decrease in cell viability were prevented by the addition of Cys, indicating that ROS are an important mediator of the antifungal action of DSEO. These findings indicate that the cytoplasmic membrane and mitochondria are the main anti-Candida targets of DSEO.

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Antifungal activity of MAF-1A peptide against Candida albicans

International Microbiology ◽

10.1007/s10123-021-00159-z ◽

2021 ◽

Author(s):

Rong Cheng ◽

Qiang Xu ◽

Fangfang Hu ◽

Hongling Li ◽

Bin Yang ◽

...

Keyword(s):

Candida Albicans ◽

Cell Membrane ◽

Antifungal Drugs ◽

Drug Resistant ◽

Fluorescent Staining ◽

Qrt Pcr ◽

Major Threat ◽

Antifungal Action ◽

Resistant Strains ◽

Drug Resistant Strains

AbstractInvasive candidiasis is a major threat to human health, and Candida albicans is the most common pathogenic species responsible for this condition. The incidence of drug-resistant strains of C. albicans is rising, necessitating the development of new antifungal drugs. Antimicrobial peptides (AMPs) have recently attracted attention due to their unique ability to evade the drug resistance of microorganisms. However, the mechanism of their activity has not yet been identified. The current study analyzed the mode of action of MAF-1A by confocal microscopy, scanning electron microscopy, fluorescent staining, flow cytometry, and qRT-PCR. The results indicate that MAF-1A disrupts the cell membrane of C. albicans and enters the cell where it binds and interacts with nucleic acids. qRT-PCR demonstrated that the expression of several sterol biosynthesis–related genes in C. albicans was increased after MAF-1A treatment. Together, these findings suggest that MAF-1A exerts antifungal action by affecting both the cell membrane and intracellular components. The antifungal mechanism of MAF-1A is unique, and its identification has great research and clinical significance.

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