TY  - JOUR
A1  - Schorn, Sina
A1  - Salman-Carvalho, Verena
A1  - Littmann, Sten
A1  - Ionescu, Danny
A1  - Grossart, Hans-Peter
A1  - Cypionka, Heribert
T1  - Cell architecture of the giant sulfur bacterium achromatium oxaliferum
BT  - Extra-cytoplasmic localization of calcium carbonate bodies
JF  - FEMS Microbiology Ecology
N2  - Achromatium oxaliferum is a large sulfur bacterium easily recognized by large intracellular calcium carbonate bodies. Although these bodies often fill major parts of the cells' volume, their role and specific intracellular location are unclear. In this study, we used various microscopy and staining techniques to identify the cell compartment harboring the calcium carbonate bodies. We observed that Achromatium cells often lost their calcium carbonate bodies, either naturally or induced by treatments with diluted acids, ethanol, sodium bicarbonate and UV radiation which did not visibly affect the overall shape and motility of the cells (except for UV radiation). The water-soluble fluorescent dye fluorescein easily diffused into empty cavities remaining after calcium carbonate loss. Membranes (stained with Nile Red) formed a network stretching throughout the cell and surrounding empty or filled calcium carbonate cavities. The cytoplasm (stained with FITC and SYBR Green for nucleic acids) appeared highly condensed and showed spots of dissolved Ca2+ (stained with Fura-2). From our observations, we conclude that the calcium carbonate bodies are located in the periplasm, in extra-cytoplasmic pockets of the cytoplasmic membrane and are thus kept separate from the cell's cytoplasm. This periplasmic localization of the carbonate bodies might explain their dynamic formation and release upon environmental changes.
KW  - sulfur-bacteria
KW  - calcium carbonate inclusions
KW  - extra-cytoplasmic pockets
KW  - calcite
Y1  - 2019
U6  - https://doi.org/10.1093/femsec/fiz200
SN  - 1574-6941
VL  - 96
IS  - 2
SP  - 1
EP  - 8
PB  - Oxford University Press
CY  - Oxford
ER  -