[Effect of polyenic antibiotics on the activity of alkaline phosphatase from Candida albicans]

Area of Science:

• Microbiology
• Biochemistry
• Antifungal Research

Background:

• Polyenic antibiotics are crucial antifungal agents targeting fungal cell membranes.
• Alkaline phosphatase is a key membrane-bound enzyme in Candida albicans.
• Understanding antibiotic-enzyme interactions is vital for antifungal drug development.

Purpose of the Study:

• To investigate the inhibitory effects of polyenic antibiotics (levorin, amphotericin B, nistatin) on membrane-bound alkaline phosphatase from Candida albicans.
• To compare the enzyme's sensitivity to these antibiotics in both sensitive and resistant strains.
• To elucidate the relationship between antibiotic concentration and enzyme inhibition.

Main Methods:

• In vitro enzyme activity assays were performed using membrane preparations from Candida albicans.
• Alkaline phosphatase activity was measured in the presence of varying concentrations of levorin, amphotericin B, and nistatin.
• Membrane protein and alkaline phosphatase solubilization was assessed after antibiotic treatment.

Main Results:

• Polyenic antibiotics demonstrated significant inhibition of alkaline phosphatase activity in sensitive Candida albicans strains.
• The inhibitory effect was approximately two times lower in the resistant strain.
• A clear correlation was observed between antibiotic concentration and the degree of enzyme inhibition, with nistatin being the least potent inhibitor.
• Antibiotic treatment did not lead to the solubilization of membrane proteins or alkaline phosphatase.

Conclusions:

• Polyenic antibiotics directly inhibit membrane-bound alkaline phosphatase in Candida albicans.
• The reduced efficacy against resistant strains suggests altered membrane properties or enzyme characteristics.
• These findings support the hypothesis that polyenic antibiotics impact cell membrane structure and function, affecting enzyme activity.