Time-course data on the use of ¹⁴C-choline by Colwellia psychrerythraea 34H following a downshift (a), no shift (b), or upshift (c) in salinity at –1°C. Grey circles (dashed lines) represent respiration, measured as ¹⁴CO₂ released upon acidification of the sample. Filled circles (solid black line) represent total amount retained intracellularly, measured as filterable material collected pre-acidification. Open circles (solid black line) represent amount incorporated into macromolecules, measured as filterable material collected post-acidification. The red line represents osmolyte retention, calculated by subtracting amount incorporated into macromolecules from total amount retained intracellularly. Error bars indicate S.D. of the mean (n = 4, except for time zero, where n = 2); where no bar is visible, it falls within the dimensions of the symbol for the mean.