1 research outputs found
Morphology and Magnetic Structure of the Ferritin Core during Iron Loading and Release by Magnetooptical and NMR Methods
Ferritins are proteins, which serve as
a storage and transportation capsule for iron inside living organisms.
Continuously charging the proteins with iron and releasing it from
the ferritin is necessary to assure proper management of these important
ions within the organism. On the other hand, synthetic ferritins have
great potential for biomedical and technological applications. In
this work, the behavior of ferritin during the processes of iron loading
and release was examined using multiplicity of the experimental technique.
The quality of the protein’s shell was monitored using circular
dichroism, whereas the average size and its distribution were estimated
from dynamic light scattering and transmission electron microscopy
images, respectively. Because of the magnetic behavior of the iron
mineral, a number of magnetooptical methods were used to gain information
on the iron core of the ferritin. Faraday rotation and magnetic linear
birefringence studies provide evidence that the iron loading and the
iron-release processes are not symmetrical. The spatial organization
of the mineral within the protein’s core changes depending
on whether the iron was incorporated into or removed from the ferritin’s
shell. Magnetic optical rotatory dispersion spectra exclude the contribution
of the Fe(II)-composed mineral, whereas joined magnetooptical and
nuclear magnetic resonance results indicate that no mineral with high
magnetization appear at any stage of the loading/release process.
These findings suggest that the iron core of loaded/released ferritin
consists of single-phase, that is, ferrihydrite. The presented results
demonstrate the usefulness of emerging magnetooptical methods in biomedical
research and applications