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Updated: Aug 18, 2026

RNAi-mediated Control of Aflatoxins in Peanut: Method to Analyze Mycotoxin Production and Transgene Expression in the Peanut/Aspergillus Pathosystem
09:44

RNAi-mediated Control of Aflatoxins in Peanut: Method to Analyze Mycotoxin Production and Transgene Expression in the Peanut/Aspergillus Pathosystem

Published on: December 21, 2015

Activation of aflatoxin B1 by a mono-oxygenase system localized in rat liver mitochondria

B G Niranjan, N G Avadhani

    The Journal of Biological Chemistry
    |July 25, 1980
    PubMed

    Insights

    Mitochondria, the powerhouses of cells, can metabolize aflatoxin B1 (AFB1). This process involves a specific mitochondrial enzyme that binds to cellular components and hinders protein synthesis.

    Area of Science:

    • Biochemistry
    • Cell Biology
    • Toxicology

    Background:

    • Aflatoxin B1 (AFB1) is a potent mycotoxin known for its toxicity and carcinogenicity.
    • Microsomal enzymes are traditionally recognized for their role in xenobiotic metabolism, including AFB1 activation.

    Purpose of the Study:

    • To investigate the presence and characteristics of AFB1-metabolizing enzymatic activity within rat liver mitoplasts.
    • To determine the subcellular localization and properties of the identified mitochondrial enzyme responsible for AFB1 activation.

    Main Methods:

    • Isolation of structurally intact rat liver mitoplasts, ensuring minimal microsomal contamination.
    • Assay of AFB1 metabolic activation in mitoplast preparations, with and without a NADPH-generating system.
    • Characterization of the enzyme's specific activity, localization, and comparison to microsomal activity.

    Main Results:

    • Rat liver mitoplasts exhibit enzymatic activity for AFB1 metabolism, independent of microsomal contamination.
    • The activated AFB1 metabolite binds to mitochondrial macromolecules and inhibits mitochondrial protein synthesis.
    • Enzymatic activity is partially dependent on NADPH and localized within the mitochondrial matrix, distinct from microsomal enzymes.

    Conclusions:

    • Mitochondria possess a unique enzymatic system for AFB1 activation, contributing to cellular toxicity.
    • This mitochondrial pathway plays a significant role in AFB1-induced damage, including inhibition of mitochondrial protein synthesis.

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