Glucosylglycerol, a compatible solute, sustains cell division under salt stress.
The cyanobacterium Synechocystis sp. PCC 6803 accumulates the compatible solute glucosylglycerol (GG) and sucrose under salt stress. Although the molecular mechanisms for GG synthesis including regulation of the GG-phosphate synthase (ggpS) gene, which encodes GgpS, has been intensively investigated, the role of GG in protection against salt stress remains poorly understood. In our study of the role of GG in the tolerance to salt stress, we found that salt stress due to 450 mM NaCl inhibited cell division and significantly increased cell size in DeltaggpS mutant cells, whereas the inhibition of cell division and increase in cell size were observed in wild-type cells at high concentrations of NaCl, such as 800 mM. Electron microscopy revealed that, in DeltaggpS cells, separation of daughter cells was incomplete, and aborted division could be recognized by the presence of a structure that resembled a division ring. The addition of GG to the culture medium protected DeltaggpS cells against salt stress and reversed the adverse effects of NaCl on cell division and cell size. These observations suggest that GG is important for salt tolerance and thus for the proper division of cells under salt stress conditions.
Ferjani
Ali
A
Department of Regulation Biology, National Institute for Basic Biology, Okazaki 444-8585, Japan.
Mustardy
Laszlo
L
Sulpice
Ronan
R
Marin
Kay
K
Suzuki
Iwane
I
Hagemann
Martin
M
Murata
Norio
N
D001426:Bacterial Proteins; D002455:Cell Division / Q000187:drug effects; D002734:Chlorophyll / Q000378:metabolism; D003470:Culture Media; D000458:Cyanobacteria / Q000166:cytology* / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D004269:DNA, Bacterial / Q000378:metabolism; D005960:Glucosides / Q000378:metabolism*; D005964:Glucosyltransferases / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D009997:Osmotic Pressure; D012965:Sodium Chloride / Q000494:pharmacology*; D013395:Sucrose / Q000378:metabolism
D001426:Bacterial Proteins; D003470:Culture Media; D004269:DNA, Bacterial; D005960:Glucosides; C034727:glucosylglycerol; D002734:Chlorophyll; D012965:Sodium Chloride; D013395:Sucrose; D005964:Glucosyltransferases; C400922:glucosylglycerol-phosphate synthase