A polypeptide model for toxic aberrant proteins induced by aminoglycoside antibiotics.
Aminoglycoside antibiotics interfere with the selection of cognate tRNAs during translation, resulting in the synthesis of aberrant proteins that are the ultimate cause of cell death. However, the toxic potential of aberrant proteins and how they avoid degradation by the cell's protein quality...
Main Authors: | , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Public Library of Science (PLoS)
2022-01-01
|
Series: | PLoS ONE |
Online Access: | https://doi.org/10.1371/journal.pone.0258794 |
_version_ | 1811307506190778368 |
---|---|
author | Mangala Tawde Abdelaziz Bior Michael Feiss Feiyue Teng Paul Freimuth |
author_facet | Mangala Tawde Abdelaziz Bior Michael Feiss Feiyue Teng Paul Freimuth |
author_sort | Mangala Tawde |
collection | DOAJ |
description | Aminoglycoside antibiotics interfere with the selection of cognate tRNAs during translation, resulting in the synthesis of aberrant proteins that are the ultimate cause of cell death. However, the toxic potential of aberrant proteins and how they avoid degradation by the cell's protein quality control (QC) machinery are not understood. Here we report that levels of the heat shock (HS) transcription factor σ32 increased sharply following exposure of Escherichia coli to the aminoglycoside kanamycin (Kan), suggesting that at least some of the aberrant proteins synthesized in these cells were recognized as substrates by DnaK, a molecular chaperone that regulates the HS response, the major protein QC pathway in bacteria. To further investigate aberrant protein toxic potential and interaction with cell QC factors, we studied an acutely toxic 48-residue polypeptide (ARF48) that is encoded by an alternate reading frame in a plant cDNA. As occurred in cells exposed to Kan, σ32 levels were strongly elevated following ARF48 expression, suggesting that ARF48 was recognized as a substrate by DnaK. Paradoxically, an internal 10-residue region that was tightly bound by DnaK in vitro also was required for the ARF48 toxic effect. Despite the increased levels of σ32, levels of several HS proteins were unchanged following ARF48 expression, suggesting that the HS response had been aborted. Nucleoids were condensed and cell permeability increased rapidly following ARF48 expression, together suggesting that ARF48 disrupts DNA-membrane interactions that could be required for efficient gene expression. Our results are consistent with earlier studies showing that aberrant proteins induced by aminoglycoside antibiotics disrupt cell membrane integrity. Insights into the mechanism for this effect could be gained by further study of the ARF48 model system. |
first_indexed | 2024-04-13T09:05:29Z |
format | Article |
id | doaj.art-73b946cab7fa45dc8474cd24a335b2f2 |
institution | Directory Open Access Journal |
issn | 1932-6203 |
language | English |
last_indexed | 2024-04-13T09:05:29Z |
publishDate | 2022-01-01 |
publisher | Public Library of Science (PLoS) |
record_format | Article |
series | PLoS ONE |
spelling | doaj.art-73b946cab7fa45dc8474cd24a335b2f22022-12-22T02:52:59ZengPublic Library of Science (PLoS)PLoS ONE1932-62032022-01-01174e025879410.1371/journal.pone.0258794A polypeptide model for toxic aberrant proteins induced by aminoglycoside antibiotics.Mangala TawdeAbdelaziz BiorMichael FeissFeiyue TengPaul FreimuthAminoglycoside antibiotics interfere with the selection of cognate tRNAs during translation, resulting in the synthesis of aberrant proteins that are the ultimate cause of cell death. However, the toxic potential of aberrant proteins and how they avoid degradation by the cell's protein quality control (QC) machinery are not understood. Here we report that levels of the heat shock (HS) transcription factor σ32 increased sharply following exposure of Escherichia coli to the aminoglycoside kanamycin (Kan), suggesting that at least some of the aberrant proteins synthesized in these cells were recognized as substrates by DnaK, a molecular chaperone that regulates the HS response, the major protein QC pathway in bacteria. To further investigate aberrant protein toxic potential and interaction with cell QC factors, we studied an acutely toxic 48-residue polypeptide (ARF48) that is encoded by an alternate reading frame in a plant cDNA. As occurred in cells exposed to Kan, σ32 levels were strongly elevated following ARF48 expression, suggesting that ARF48 was recognized as a substrate by DnaK. Paradoxically, an internal 10-residue region that was tightly bound by DnaK in vitro also was required for the ARF48 toxic effect. Despite the increased levels of σ32, levels of several HS proteins were unchanged following ARF48 expression, suggesting that the HS response had been aborted. Nucleoids were condensed and cell permeability increased rapidly following ARF48 expression, together suggesting that ARF48 disrupts DNA-membrane interactions that could be required for efficient gene expression. Our results are consistent with earlier studies showing that aberrant proteins induced by aminoglycoside antibiotics disrupt cell membrane integrity. Insights into the mechanism for this effect could be gained by further study of the ARF48 model system.https://doi.org/10.1371/journal.pone.0258794 |
spellingShingle | Mangala Tawde Abdelaziz Bior Michael Feiss Feiyue Teng Paul Freimuth A polypeptide model for toxic aberrant proteins induced by aminoglycoside antibiotics. PLoS ONE |
title | A polypeptide model for toxic aberrant proteins induced by aminoglycoside antibiotics. |
title_full | A polypeptide model for toxic aberrant proteins induced by aminoglycoside antibiotics. |
title_fullStr | A polypeptide model for toxic aberrant proteins induced by aminoglycoside antibiotics. |
title_full_unstemmed | A polypeptide model for toxic aberrant proteins induced by aminoglycoside antibiotics. |
title_short | A polypeptide model for toxic aberrant proteins induced by aminoglycoside antibiotics. |
title_sort | polypeptide model for toxic aberrant proteins induced by aminoglycoside antibiotics |
url | https://doi.org/10.1371/journal.pone.0258794 |
work_keys_str_mv | AT mangalatawde apolypeptidemodelfortoxicaberrantproteinsinducedbyaminoglycosideantibiotics AT abdelazizbior apolypeptidemodelfortoxicaberrantproteinsinducedbyaminoglycosideantibiotics AT michaelfeiss apolypeptidemodelfortoxicaberrantproteinsinducedbyaminoglycosideantibiotics AT feiyueteng apolypeptidemodelfortoxicaberrantproteinsinducedbyaminoglycosideantibiotics AT paulfreimuth apolypeptidemodelfortoxicaberrantproteinsinducedbyaminoglycosideantibiotics AT mangalatawde polypeptidemodelfortoxicaberrantproteinsinducedbyaminoglycosideantibiotics AT abdelazizbior polypeptidemodelfortoxicaberrantproteinsinducedbyaminoglycosideantibiotics AT michaelfeiss polypeptidemodelfortoxicaberrantproteinsinducedbyaminoglycosideantibiotics AT feiyueteng polypeptidemodelfortoxicaberrantproteinsinducedbyaminoglycosideantibiotics AT paulfreimuth polypeptidemodelfortoxicaberrantproteinsinducedbyaminoglycosideantibiotics |