Protein Density

[Astronuc]

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Just in case someone needs this information.

Average protein density is a molecular-weight-dependent function
http://www.proteinscience.org/cgi/content/full/13/10/2825

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.

http://www.proteinscience.org/cgi/reprint/13/10/2825.pdf (use save target as)