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Updated: Sep 5, 2026

Metabolic Profiling to Determine Bactericidal or Bacteriostatic Effects of New Natural Products using Isothermal Microcalorimetry
07:28

Metabolic Profiling to Determine Bactericidal or Bacteriostatic Effects of New Natural Products using Isothermal Microcalorimetry

Published on: October 29, 2020

EFFECT OF TETRACYCLINES ON THE INTRACELLULAR AMINO ACIDS OF MOLDS

B A FREEMAN, R CIRCO

    Journal of Bacteriology
    |July 1, 1963
    PubMed

    Insights

    Tetracycline antibiotics alter mold amino acid metabolism, reducing intracellular levels of most amino acids. Some amino acids like glutamic acid and alanine were unaffected, while others disappeared entirely.

    Area of Science:

    • Microbiology
    • Biochemistry
    • Molecular Biology

    Background:

    • Antibiotics, such as tetracyclines, are known to affect microbial metabolism.
    • Understanding the specific metabolic pathways influenced by antibiotics is crucial for elucidating their mechanisms of action.

    Purpose of the Study:

    • To investigate the impact of tetracycline antibiotics on the intracellular amino acid composition of various mold species.
    • To determine if tetracyclines affect amino acid metabolism in molds even when growth is not significantly inhibited.

    Main Methods:

    • Eight different mold species were cultured in the presence of tetracycline antibiotics.
    • Intracellular amino acid concentrations were analyzed using biochemical methods.

    Main Results:

    • Tetracyclines altered amino acid metabolism in four out of eight tested molds.
    • A general decrease in intracellular amino acids was observed, with notable exceptions of glutamic acid and alanine.
    • Arginine, lysine, proline, phenylalanine, and tyrosine were found to be depleted from the intracellular pool in affected cultures.

    Conclusions:

    • Tetracyclines can significantly alter intracellular amino acid pools in molds, independent of major growth inhibition.
    • These findings highlight the utility of analyzing amino acid metabolism to understand antibiotic mechanisms.
    Keywords:
    AMINO ACIDSFUNGITETRACYCLINE

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