Effect of compensatory organic osmolytes on resistance to freeze-drying ofL929 cells and of their isolated chromatin

(1) Compensatory organic osmolytes are stabilizers of macromolecular struct ures. During acclimation to dehydration or high salinity, they accumulate i n cells and effectively protect them against disruption that might otherwis e result from increased inorganic ion concentrations. (2) Circular and elec tric dichroism, analysis of the kinetics of digestion by micrococcal nuclea se, and UV spectra between 190 and 305 nm were used to investigate the resi stance to dehydration upon freezing or freeze-drying that could confer such compounds to chromatin isolated from cultured L929 cells. Some work was al so done on intact cells in vivo. (3) Sorbitol, sucrose, and trehalose appea r to protect isolated chromatin very effectively; proline is less effective . (4) These compounds also effectively protect chromatin from the disruptin g effects of NaCl. (5) Cells loaded and grown with sorbitol, sucrose, or pr oline can tolerate larger decreases in hydration than control cells. They c annot, however, tolerate complete dehydration. (C) 1999 Elsevier Science In c. All rights reserved.