title: Sinusoidal magnetic field stimulates magnetosome formation and affects mamA, mms13, mms6, and magA expression in Magnetospirillum magneticum AMB-1.
abstract: Magnetic particles are currently one of the most important materials in the industrial sector, where they have been widely used for biotechnological and biomedical applications. To investigate the effects of the imposed magnetic field on biomineralization in Magnetospirillum magneticum AMB-1 and to suggest a new approach that enhances formation of magnetosomes, cultures inoculated with either magnetic or nonmagnetic precultures were incubated under a sinusoidal magnetic field or geomagnetic field. The results showed that the sinusoidal magnetic field up-regulated mms6 expression in the cultures inoculated with magnetic cells, and magA, mms6, and mamA expression in the cultures inoculated with nonmagnetic cells. The applied sinusoidal magnetic field could block cell division, which could contribute to a decrease in the OD600 values and an increase in the coefficient of magnetism values of the cultures, which could mean that the percentage of mature magnetosome-containing bacteria was increased. The linearity of magnetosome chains was affected, but the number of magnetic particles in cells was increased when a sinusoidal magnetic field was applied to the cultures. The results imply that the variable intensity and orientation of the sinusoidal magnetic field resulted in magnetic pole conversion in the newly forming magnetic particles, which could affect the formation of magnetic crystals and the arrangement of the adjacent magnetosome.
authors.affiliation: Weifang Medical University, Weifang 261053, China. wangxiaoke1962@yahoo.com.cn
authors.forename: Xiaoke
authors.initials: X
authors.lastname: Wang
authors.forename: Likun
authors.initials: L
authors.lastname: Liang
authors.forename: Tao
authors.initials: T
authors.lastname: Song
authors.forename: Longfei
authors.initials: L
authors.lastname: Wu
mesh_terms: D000222:Adaptation, Physiological; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D001709:Biotechnology; D027682:Cation Transport Proteins / Q000096:biosynthesis* / Q000235:genetics; D002455:Cell Division; D022162:Cytoplasmic Vesicles / Q000378:metabolism*; D004574:Electromagnetic Fields; D015964:Gene Expression Regulation, Bacterial; D042201:Magnetospirillum / Q000166:cytology / Q000235:genetics* / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D001426:Bacterial Proteins; D027682:Cation Transport Proteins; C097085:MagA protein, Magnetospirillum