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bioRxiv · 10.1101/2025.02.20.639248

Metalation calculator for E. coli strain BW25113 grown in M9 minimal media

Clough, S. E.·Glasfeld, A.·Robinson, N. J.
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Abstract

Here we provide the background data supporting an additional web-based calculator to predict in-cell metalation of proteins within E. coli BW25113 grown in M9 media. Intracellular metal availabilities have been estimated from the calibrated responses of DNA-binding, metal-sensing, transcriptional regulators. We have previously tested and validated metalation calculator predictions. They confirm that when proteins are expressed heterologously in E. coli in LB medium, they can become mismatched to metal availability and be mismetalated. Mg2+GTP-CobW from Rhodobacter is predicted to be correctly metalated with cobalt in E. coli grown in M9 media, although mismetalated with zinc in LB-grown heterologous cells. Similarly, MncA from Synechocystis PCC 6803 is predicted to be correctly metalated with manganese in E. coli grown in M9 media, although mismetalated with iron in LB-grown heterologous cells. The M9 metalation calculator is available online and as a spreadsheet for use in optimising metalation in engineering biology. An MncA-refined metalation calculator for idealised cells, reflecting the midpoint of intracellular metal availabilities, is also included and available online.

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Clough, S. E., Glasfeld, A., Robinson, N. J.. 2025-02-22. Metalation calculator for E. coli strain BW25113 grown in M9 minimal media. https://doi.org/10.1101/2025.02.20.639248

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