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Average protein density is a molecular-weight-dependent function.

Hannes Fischer·Igor Polikarpov·Aldo F Craievich
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Abstract

The mass density of proteins is a relevant basic biophysical quantity. It is also a useful input parameter, for example, for three-dimensional structure determination by protein crystallography and studies of protein oligomers in solution by analytic ultracentrifugation. We have performed a critical analysis of published, theoretical, and experimental investigations about this issue and concluded that the average density of proteins is not a constant as often assumed. For proteins with a molecular weight below 20 kDa, the average density exhibits a positive deviation that increases for decreasing molecular weight. A simple molecular-weight-depending function is proposed that provides a more accurate estimate of the average protein density.

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Computational BiologyCrystallographyMolecular WeightProtein ConformationProteinsUltracentrifugationJournal ArticleResearch Support, Non-U.S. Gov't

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Hannes Fischer, Igor Polikarpov, Aldo F Craievich. 2004. Average protein density is a molecular-weight-dependent function.. https://doi.org/10.1110/ps.04688204

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