title: Intracellular magneto-spatial organization of magnetic organelles inside intact bacterial cells.
abstract: Magnetotactic bacteria naturally produce magnetosomes, i.e., biological membrane bound nanomagnets, at ambient conditions. It is important to understand simultaneously the possible size variations and the magnetic behavior of nano-magnets inside intact bacterial cells for both applicational purposes as well as to enhance the basic understanding of biomineralization leading to intracellular nano-magnet synthesis. In this work, we utilize High-resolution Transmission Electron Microscopy and Near-field Scanning Optical Microscopy based measurements on intact non-fixed single cells to rigorously and quantitatively understand the intra-cellular magneto-spatial distribution of nano-magnets synthesized by Magnetospirillum gryphiswaldense. We demonstrate that it is possible to measure the relative magnetic moments along the intracellular magnetosomal chains for intact and non-fixed bacterial cells. Using our in vivo measurements on several single cells, we report that magnetic behavior of intracellular nano-magnets synthesized by magnetotactic bacteria depend on their relative location in the magnetosomal chains. Our work opens promising avenues in the direction of measuring the magnetic behavior of nano-magnets inside living systems by utilizing an operationally straight-forward approach.
authors.affiliation: Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi 110016, India.
authors.forename: Mohit
authors.initials: M
authors.lastname: Naresh
authors.forename: Manish
authors.initials: M
authors.lastname: Sharma
authors.forename: Aditya
authors.initials: A
authors.lastname: Mittal
mesh_terms: D008280:Magnetics; D055944:Magnetosomes / Q000737:chemistry* / Q000648:ultrastructure*; D042201:Magnetospirillum / Q000737:chemistry* / Q000648:ultrastructure*; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D036103:Nanotechnology