Snapping magnetosome chains by asymmetric cell division in magnetotactic bacteria

Authors

  • Wei Lin,

    1. Biogeomagnetism Group, Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth's Deep Interior, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
    2. France-China Bio-Mineralization and Nano-Structures Laboratory, Chinese Academy of Sciences, Beijing 100029, China
    Search for more papers by this author
  • Yongxin Pan

    Corresponding author
    1. Biogeomagnetism Group, Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth's Deep Interior, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
    2. France-China Bio-Mineralization and Nano-Structures Laboratory, Chinese Academy of Sciences, Beijing 100029, China
    Search for more papers by this author

  • Editorial note: Since this article was first published on Wiley Online Library Early View on 8 November 2011, it has been updated in the following ways due to factual information that subsequently came available. Changes have been made to reflect developmental editing of Katzmann et al. (2011), intended to aide readers in connecting this study to earlier work on the subject.

E-mail yxpan@mail.iggcas.ac.cn; Tel. (+86) (0)10 8299 8406; Fax (+86) (0)10 6201 0846.

Summary

The mechanism by which prokaryotic cells organize and segregate their intracellular organelles during cell division has recently been the subject of substantial interest. Unlike other microorganisms, magnetotactic bacteria (MTB) form internal magnets (known as magnetosome chain) for magnetic orientation, and thus face an additional challenge of dividing and equipartitioning this magnetic receptor to their daughter cells. Although MTB have been investigated more than four decades, it is only recently that the basic mechanism of how MTB divide and segregate their magnetic organelles has been addressed. In this issue of Molecular Microbiology, the cell cycle of the model magnetotactic bacterium, Magnetospirillum gryphiswaldense is characterized by Katzmann and co-workers. The authors have found that M. gryphiswaldense undergoes an asymmetric cell division along two planes. A novel wedge-like type of cellular constriction is observed before separation of daughter cells and magnetosome chains, which is assumed to help cell cope with the magnetic force within the magnetosome chain. The data shows that the magnetosome chain becomes actively recruited to the cellular division site, in agreement with the previous suggestions described by Staniland et al. (2010), and the actin-like protein MamK is likely involved in this fast polar-to-midcell translocalization. With the use of cryo-electron tomography, an arc-shaped Z ring is observed near the division site, which is assumed to trigger the asymmetric septation of cell and magnetosome chain.

Ancillary