Biogenic nanoparticles: production, characterization, and application of bacterialmagnetosomes

Abstract

The ability of magnetotactic bacteria (MTB) to navigate along magnetic field lines is basedon unique nanosized organelles (magnetosomes), which are membrane-enclosed intracellularcrystals of a magnetic iron mineral that assemble into highly ordered chain-like structures.The biomineralization of magnetosomes is a process with genetic control over theaccumulation of iron, the deposition of the magnetic crystal within a specific compartment,as well as the assembly, alignment and intracellular organization of particle chains.Magnetite crystals produced by MTB have uniform species-specific morphologies and sizes,which are mostly unknown from inorganic systems. The unusual characteristics ofmagnetosome particles have attracted a great interdisciplinary interest and inspirednumerous ideas for their biotechnological application. In this article, we summarize thecurrent knowledge of magnetosome biomineralization in bacteria. In addition, we willpresent results on the mass production, as well as the biochemical and physico-chemicalanalysis and functionalization of bacterial magnetosomes, with emphasis on theircharacterization as a novel class of magnetic nanoparticles. Finally, we describe thepotential of magnetosomes in various biomedical and technological applications.