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Updated: Jul 19, 2026

Sedimentation Equilibrium of a Small Oligomer-forming Membrane Protein: Effect of Histidine Protonation on Pentameric Stability
Published on: April 2, 2015
Calculated sedimentation ratios for assemblies of two, three, four, and five spatially equivalent protomers
1Department of Physical Biochemistry, John Curtin School of Medical Research, Australian National University Canberra, A.C.T. 2601, Australia.
Abstract:
Sedimentation ratios of oligomeric structures containing from two to five protomers in spatially equivalent positions are calculated on the basis of equations derived by Kirkwood. A range of oblate and prolate protomers and a systematic set of assembly modes is considered for each type of oligomer. The results are presented graphically. Dimensions in three mutually perpendicular directions are also given for each structure considered, in a format which allows calculation in A of the dimensions of appropriate models for actual molecules. Together with the results for hexameric aggregates presented previously these data allow sedimentation velocity measurements with any oligomer, up to and including the hexamer, to be analysed readily and systematically in terms of quaternary structure.
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