The Stalk of the Suctorian Tokophrya infusionum: Histochemistry, Biochemistry, and Physiology |
| |
Authors: | GRETCHEN K HASCALL |
| |
Institution: | Rockefeller University, New York, New York 10021 |
| |
Abstract: | Tokophrya infusionum, a sessile suctorian with an external stalk and adhesive disc, has in its life cycle a ciliated, swimming embryo which metamorphoses into the adult form. The addition of NiCl2 to the medium induced metamorphosis immediately; however, other salts had no effect. Incomplete metamorphosis, without stalk formation, occurred if the organism began metamorphosis before its anterior (stalk-forming) end touched a substrate. The stalk was studied by histochemical and biochemical technics to determine its composition. The stalk stained with mercury-bromphenol blue, and Alcian blue under a variety of conditions, but not with PAS. These results suggest that the stalk contains protein and sulfate groups, possibly in the form of a sulfated protein-polysaccharide. The stalk was insoluble in several common laboratory reagents, but did dissolve in hot 6 N HCl, 2 N NaOH, and papain. It was evident from amino acid analysis of the stalk and of the whole organism that 15% of the total protein is located in the stalk. |
| |
Keywords: | Tokophrya infusionum metamorphosis induction by nickel salts stalk histochemical and biochemical analyses of |
|
|