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Published on: October 25, 2024
Antimitochondrial activity displayed by the antimicrobial peptide microcin J25
María V Niklison Chirou1, Carlos J Minahk, Roberto D Morero
1Departamento de Bioquímica de la Nutrición, Instituto Superior de Investigaciones Biológicas, Instituto de Química Biológica Dr. Bernabé Bloj, 4000 San Miguel de Tucumán, Argentina.
Abstract:
In this report we studied the effect of the antimicrobial peptide, microcin J25, on the rat heart mitochondria. This peptide induced an important inhibition of the ATP synthesis with the concomitant enhancement of the ATP degradation. These effects were the result of two processes: on one hand, microcin J25 was able to insert into the membrane and hence alter its permeability with the consequent dissipation of the proton motive force. On the other, microcin J25 inhibited the enzymatic activity of the cytochrome c reductase (complex III) of the respiratory chain. The relevance of this study to the potential use of microcin J25 as an anti-tumoral agent is discussed.
Insights
The antimicrobial peptide microcin J25 significantly disrupts rat heart mitochondria by inhibiting ATP synthesis and degrading ATP. It alters mitochondrial membrane permeability and inhibits Complex III activity, suggesting potential anti-cancer applications.
Area of Science:
- Biochemistry
- Molecular Biology
- Pharmacology
Background:
- Mitochondria are crucial for cellular energy production.
- Antimicrobial peptides are being investigated for therapeutic potential.
- Microcin J25 is a known antimicrobial peptide.
Purpose of the Study:
- To investigate the effects of microcin J25 on rat heart mitochondria.
- To elucidate the mechanisms by which microcin J25 affects mitochondrial function.
Main Methods:
- Isolated rat heart mitochondria were used.
- ATP synthesis and degradation rates were measured.
- Mitochondrial membrane permeability and proton motive force were assessed.
- Enzymatic activity of cytochrome c reductase (Complex III) was analyzed.
Main Results:
- Microcin J25 significantly inhibited ATP synthesis.
- ATP degradation was enhanced by microcin J25.
- The peptide altered mitochondrial membrane permeability, dissipating the proton motive force.
- Microcin J25 inhibited the activity of cytochrome c reductase (Complex III).
Conclusions:
- Microcin J25 exerts its effects through two primary mechanisms: altering mitochondrial membrane permeability and inhibiting Complex III.
- These findings highlight the potent impact of microcin J25 on mitochondrial bioenergetics.
- The study discusses the potential of microcin J25 as an anti-tumoral agent due to its mitochondrial effects.
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