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Structure and stability of self-assembled actin-lysozyme complexes in salty water

Lori K. Sanders·Camilo Guaqueta·Thomas E. Angelini·Jae-Wook Lee·Scott C. Slimmer·Erik Luijten·Gerard C. L. Wong
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Abstract

Interactions between actin, an anionic polyelectrolyte, and lysozyme, a cationic globular protein, have been examined using a combination of synchrotron small-angle x-ray scattering and molecular dynamics simulations. Lysozyme initially bridges pairs of actin filaments, which relax into hexagonally-coordinated columnar complexes comprised of actin held together by incommensurate one-dimensional close-packed arrays of lysozyme macroions. These complexes are found to be stable even in the presence of significant concentrations of monovalent salt, which is quantitatively explained from a redistribution of salt between the condensed and the aqueous phases.

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Lori K. Sanders, Camilo Guaqueta, Thomas E. Angelini, Jae-Wook Lee, Scott C. Slimmer, Erik Luijten, Gerard C. L. Wong. 2005-07-25. Structure and stability of self-assembled actin-lysozyme complexes in salty water. https://doi.org/10.1103/physrevlett.95.108302

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