Magnetosome vesicles are present before magnetite formation, and MamA is required for their activation.
Bacterial magnetosomes are intracellular compartments that house highly ordered magnetite crystals. By using Magnetospirillum sp. AMB-1 as a model system, we show that magnetosome vesicles exist in the absence of magnetite, biomineralization of magnetite proceeds simultaneously in multiple vesicles, and biomineralization proceeds from the same location in each vesicle. The magnetosome-associated protein, MamA, is required for the formation of functional magnetosome vesicles and displays a dynamic subcellular localization throughout the growth cycle of magnetotactic bacteria. Together, these results suggest that the magnetosome precisely coordinates magnetite biomineralization and can serve as a model system for the study of organelle biogenesis in noneukaryotic cells.
Division of Geological and Planetary Sciences, California Institute of Technology, Mail Stop 100-23, Pasadena, CA 91125, USA.
Arash
A
Komeili
Hojatollah
H
Vali
Terrance J
TJ
Beveridge
Dianne K
DK
Newman
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D022162:Cytoplasmic Vesicles / Q000378:metabolism*; D052203:Ferrosoferric Oxide; D017930:Genes, Reporter; D007501:Iron / Q000378:metabolism*; D042201:Magnetospirillum / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010087:Oxides / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion; D013997:Time Factors
D001426:Bacterial Proteins; D010087:Oxides; D011993:Recombinant Fusion Proteins; D007501:Iron; D052203:Ferrosoferric Oxide