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Novel mitochondrial complex I-inhibiting peptides restrain NADH dehydrogenase activity.

ABSTRACT: The emergence of drug-resistant fungal pathogens is becoming increasingly serious due to overuse of antifungals. Antimicrobial peptides have potent activity against a broad spectrum of pathogens, including fungi, and are considered a potential new class of antifungals. In this study, we examined the activities of the newly designed peptides P-113Du and P-113Tri, together with their parental peptide P-113, against the human fungal pathogen Candida albicans. The results showed that these peptides inhibit mitochondrial complex I, specifically NADH dehydrogenase, of the electron transport chain. Moreover, P-113Du and P-113Tri also block alternative NADH dehydrogenases. Currently, most inhibitors of the mitochondrial complex I are small molecules or artificially-designed antibodies. Here, we demonstrated novel functions of antimicrobial peptides in inhibiting the mitochondrial complex I of C. albicans, providing insight in the development of new antifungal agents.

SUBMITTER: Xue YP

PROVIDER: S-EPMC6757105 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Novel mitochondrial complex I-inhibiting peptides restrain NADH dehydrogenase activity.

Xue Yao-Peng YP Kao Mou-Chieh MC Lan Chung-Yu CY

Scientific reports 20190923 1

The emergence of drug-resistant fungal pathogens is becoming increasingly serious due to overuse of antifungals. Antimicrobial peptides have potent activity against a broad spectrum of pathogens, including fungi, and are considered a potential new class of antifungals. In this study, we examined the activities of the newly designed peptides P-113Du and P-113Tri, together with their parental peptide P-113, against the human fungal pathogen Candida albicans. The results showed that these peptides ...[more]

PMID: 31548559

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