title: Greigite magnetosome membrane ultrastructure in 'Candidatus Magnetoglobus multicellularis'.
abstract: The ultrastructure of the greigite magnetosome membrane in the multicellular magnetotactic bacteria 'Candidatus Magnetoglobus multicellularis' was studied. Each cell contains 80 membrane-enclosed iron-sulfide magnetosomes. Cytochemistry methods showed that the magnetosomes are enveloped by a structure whose staining pattern and dimensions are similar to those of the cytoplasmic membrane, indicating that the magnetosome membrane likely originates from the cytoplasmic membrane. Freeze-fracture showed intramembrane particles in the vesicles surrounding each magnetosome. Observations of cell membrane invaginations, the trilaminar membrane structure of immature magnetosomes, and empty vesicles together suggested that greigite magnetosome formation begins by invagination of the cell membrane, as has been proposed for magnetite magnetosomes.
authors.affiliation: Professor Paulo de Góes Institute of Microbiology, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Fernanda P
authors.initials: FP
authors.lastname: Abreu
authors.forename: Karen T
authors.initials: KT
authors.lastname: Silva
authors.forename: Marcos
authors.initials: M
authors.lastname: Farina
authors.forename: Carolina N
authors.initials: CN
authors.lastname: Keim
authors.forename: Ulysses
authors.initials: U
authors.lastname: Lins
mesh_terms: D015415:Biomarkers; D002462:Cell Membrane / Q000648:ultrastructure*; D020564:Deltaproteobacteria / Q000648:ultrastructure*; D006651:Histocytochemistry; D002479:Inclusion Bodies / Q000648:ultrastructure*; D007501:Iron; D008280:Magnetics; D046529:Microscopy, Electron, Transmission; D013440:Sulfides
chemical_list: D015415:Biomarkers; D013440:Sulfides; C111959:greigite; D007501:Iron