Osmoregulation osmolytes

DMSP (21) is produced by many marine micro- and macroalgae and is especially prominent in dinoflagellates and haptophytes. The nontoxic DMSP (21) fulfills multiple cellular functions including cryoprotection, the involvement as osmolyte in osmoregulation and as a methyl donor in transmethylation reactions [18]. 

Rates of DNA synthesis are sensitive to osmolality in both prokaryotic and eukaryotic cells. In bacteria, hyperosmolality led to a decrease in the frequency of initiation of DNA synthesis and, possibly for this reason, to an inhibition of cytokinesis (Meury, 1988). Glycine betaine was able to restore DNA synthesis, illustrating yet another benefit of relying on compatible organic osmolytes in osmoregulation. In mammalian cells, hyperosmolality has been found to both impede and increase DNA synthesis, depending on the cell types being studied and experimental conditions (Kiiltz, 2000). 

Low, P.S. (1985). Molecular basis of the biological compatibility of nature s osmolytes. In Transport Processes, Iono- and Osmoregulation, pp. 467—477, ed. R. Gilles and M. Gilles-Ballien. Berlin Springer-V erlag. 

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