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Updated: May 23, 2026
Small-Scale Plasma Membrane Preparation for the Analysis of Candida albicans Cdr1-mGFPHis
Published on: June 13, 2021
In vivo direct interaction of the antibiotic primycin on a Candida albicans clinical isolate and its ergosterol-less
Eszter Virág1, A Juhász, R Kardos
1Department of General and Environmental Microbiology, Faculty of Sciences, University of Pécs, Hungary.
Abstract:
Interaction of primycin antibiotic with plasma membrane, and its indirect biological effects were investigated in this study. The antifungal activity of primycin against 13 human pathogenic Candida ATCC and CBS reference species and 74 other Candida albicans clinical isolates was investigated with a microdilution technique. No primycin-resistant strain was detected. Direct interaction of primycin with the plasma membrane was demonstrated for the first time by using an ergosterol-producing strain 33erg+ and its ergosterol-less mutant erg-2. In growth inhibition tests, the 33erg+ strain proved to be more sensitive to primycin than its erg-2 mutant, indicating the importance of the plasma membrane composition in primycin-induced processes. The 64 μg ml-1 (56.8 nM) primycin treatment induced an enhanced membrane fluidity and altered plasma membrane dynamics, as measured by steady-state fluorescence anisotropy applying a trimethylammonium-diphenylhexatriene (TMA-DPH) fluorescence polarization probe. The following consequences were detected. The plasma membrane of the cells lost its barrier function, and the efflux of 260-nm-absorbing materials from treated cells of both strains was 1.5-1.8 times more than that for the control. Depending on the primycin concentration, the cells exhibited unipolar budding, pseudohyphae formation, and a rough cell surface visualized by scanning electron microscopy.
Insights
The antifungal primycin antibiotic interacts directly with the plasma membrane, disrupting its function and causing cell death in Candida species. This study demonstrates primycin
Area of Science:
- Mycology
- Antimicrobial Research
- Cell Biology
Background:
- Candida species are significant human pathogens.
- Understanding antifungal mechanisms is crucial for developing new treatments.
- Primycin is an antibiotic with potential antifungal properties.
Purpose of the Study:
- To investigate the antifungal activity of primycin against Candida species.
- To elucidate the direct interaction of primycin with the fungal plasma membrane.
- To determine the indirect biological effects of primycin on Candida cells.
Main Methods:
- Microdilution technique for antifungal susceptibility testing.
- Use of ergosterol-producing and ergosterol-less Candida strains.
- Measurement of plasma membrane fluidity using fluorescence anisotropy (TMA-DPH probe).
- Scanning electron microscopy for visualizing cell surface changes.
Main Results:
- No primycin-resistant Candida strains were detected.
- Primycin directly interacts with the plasma membrane, with sensitivity dependent on ergosterol content.
- Primycin treatment increased membrane fluidity, impaired barrier function, and induced cell morphology changes.
Conclusions:
- Primycin's antifungal activity is linked to its direct interaction with the plasma membrane.
- Alterations in membrane composition affect sensitivity to primycin.
- Primycin disrupts membrane integrity, leading to cell death and morphological changes in Candida.
