Physiological changes accompanying the recovery of cell division in "giant" cells of Chlorella vulgaris (EMERSON strain)

A homogeneous population of "giant" cells of the EMERSON strainof Chlorella vulgaris, produced following culture under carefullycontrolled conditions in a glucose medium in the dark, recoversits capacity to undergo cell division when returned to autotrophicconditions. A similar recovery also occurs after a prolongedperiod of culture in the dark. The division of the giant cellsis accompanied, in each case, by marked pigment synthesis anda consequent recovery of photosynthetic capacity. Under autotrophicconditions the recovery of cell division and restoration ofthe full pigment concentration are complete within a 24 hr period.The recovery which takes place in a glucose medium in the darkoccurs only after a period of 10–14 days growth. (Received May 9, 1970; )