Water stabilizes an alternate turn conformation in horse heart myoglobin

Marx, A.; Bronstein, A. M.

doi:10.1101/2023.01.15.524139

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bioRxiv · 10.1101/2023.01.15.524139

Water stabilizes an alternate turn conformation in horse heart myoglobin

Marx, A.·Bronstein, A. M.

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Abstract

Comparison of myoglobin structures reveals that protein isolated from horse heart consistently adopts an alternate turn conformation in comparison to its homologues. Analysis of hundreds of high-resolution structures discounts crystallization conditions or the surrounding amino acid protein environment as explaining this difference, that is also not captured by the AlphaFold prediction. Rather, a water molecule is identified as stabilizing the conformation in the horse heart structure, which immediately reverts to the whale conformation in molecular dynamics simulations excluding that structural water.

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Marx, A., Bronstein, A. M.. 2023-01-16. Water stabilizes an alternate turn conformation in horse heart myoglobin. https://doi.org/10.1101/2023.01.15.524139

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