Synthetic biological macromolecule of magnetoferritin containing an iron oxide core inside a protein shell (apoferritin) is prepared with different content of iron. Its structure in aqueous solution is analyzed by small-angle synchrotron X-ray (SAXS) and neutron (SANS) scattering. The loading factor (LF) defined as the average number of iron atoms per protein is varied up to LF=800. With an increase of the LF, the scattering curves exhibit a relative increase in the total scattered intensity, a partial smearing and a shift of the match point in the SANS contrast variation data. The analysis shows an increase in the polydispersity of the proteins and a corresponding effective increase in the relative content of magnetic material against the protein moiety of the shell with the LF growth. At LFs above ~150, the apoferritin shell undergoes structural changes, which is strongly indicative of the fact that the shell stability is affected by iron oxide presence.
@article{arxiv.1702.00350,
title = {Effect of iron oxide loading on magnetoferritin structure in solution as revealed by SAXS and SANS},
author = {L. Melníková and V. I. Petrenko and M. V. Avdeev and V. M. Garamus and L. Almásy and O. I. Ivankov and L. A. Bulavin and Z. Mitróová and P. Kopčanský},
journal= {arXiv preprint arXiv:1702.00350},
year = {2017}
}