Physical Characteristics of Magnetic Bacteria and Their Electromagnetic Properties in the Frequency Range of 1 - 400 GHz
Abstract
Basic D.C. magnetic and gigahertz properties of magnetosome chains in the magnetotactic bacterium Aquaspirillium magnetotacticum were investigated. Cell yield in fermenter grown and batch cultures were increased by over an order of magnitude to 5 x 10 to the 9th power cells/ml, making large-scale production of A. magnetotacticum and magnetosomes possible. D.C. hysteresis and A.C. gigahertz remanence studies were carried out on whole cells, separated magnetosome chains and cells aligned on substrates. The results were compared with synthetic FE3O4 (Iron 3 Oxygen 4) and gamma-Fe2O3 particles. Electromagnetic absorption is zero and in applied magnetic fields was determined up to 400 gigahertz for cells suspended in an inert binder. Birefringence of an aligned sample was detected. Magnetosomes in cells were shown to be enveloped by phospholipid bilayer membranes with membrane proteins, some of which are not present in the cellular plasma membrane. Research was also initiated on genetic transfer of magnetosome production, and on bioaccumulation by A. magnetotacticum of Pu4+ (platonium) and other heavy metal ions from water. Keywords: Magnetotactic bacteria.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 14, 1987
- Accession Number
- ADA220600