Work horse strain Clostridioides difficile 630Δerm is oblivious to its anaerobic lifestyle

Troitzsch, D.; Zhang, H.; Dittmann, S.; Düsterhöft, D.; Michel, A.-M.; Jänsch, L.; Riedel, K.; Borrero-de Acuna, J. M.; Jahn, D.; Sievers, S.

doi:10.1101/2020.01.07.897181

bioRxiv · 10.1101/2020.01.07.897181

Work horse strain Clostridioides difficile 630Δerm is oblivious to its anaerobic lifestyle

Troitzsch, D.·Zhang, H.·Dittmann, S.·Düsterhöft, D.·Michel, A.-M.·Jänsch, L.·Riedel, K.·Borrero-de Acuna, J. M.·Jahn, D.·Sievers, S.

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Abstract

The laboratory reference strain 630{Delta}erm of the anaerobic human pathogen Clostridioides difficile is characterized by a remarkable high oxygen tolerance. We show that an amino acid exchange in the DNA binding domain of the hydrogen peroxide sensor PerR results in a constitutive derepression of PerR-controlled genes and thus in an oxidative stress response even under anaerobic conditions. This questions the model status, strain 630{Delta}erm claims in C. difficile research.

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Troitzsch, D., Zhang, H., Dittmann, S., Düsterhöft, D., Michel, A.-M., Jänsch, L., Riedel, K., Borrero-de Acuna, J. M., Jahn, D., Sievers, S.. 2020-01-08. Work horse strain Clostridioides difficile 630Δerm is oblivious to its anaerobic lifestyle. https://doi.org/10.1101/2020.01.07.897181

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