A Biochemical and Autoradiographic Study of the Role of the Golgi Bodies in Thecal Formation inPlatymonas tetrathele

Abstract

Hydrolysates of the theca of Platymonas tetrathele have shown that it is a pectin-like material with galactose, galacturonic acid, and arabinose as the major components. Exogenous glucose or galactose taken up by the alga is incorporated into the theca and into starch, but is not respired. Electron microscopic autoradiography has been used to trace the incorporation of tritiated glucose into starch and into polysaccharides in the Golgi bodies and subsequentlyinto the theca. The extracellular polysaccharide produced by this alga is similar to the theca in composition and may have a common origin.