Sulfur deprivation is imposed upon the cells in the
growth medium, either by carefully limiting sulfur supply
so that it is consumed entirely, or by permitting cells
to concentrate in the growth chamber prior to medium
replacement with one that lacks sulfur nutrients. Cells
respond to this S-deprivation by fundamentally altering
photosynthesis and cellular metabolism in order to survive
[57–59]. Noteworthy in this respect is the 10-fold
increase in cellular starch content during the ,rst 24 h
of S-deprivation