Electron Microscope and Optical Diffraction Studies on Isolated Cell Walls from Chlamydomonas

Abstract

THERE are few high resolution electron microscope studies specifically concerned with the architecture of the cell walls of the green alga Chlamydomonas. Sager and Palade¹ state that the wall of C. reinhardi is a multilayered structure about 40.0 nm thick and that the structure is consistent with the cellulose wall described from light microscope observations. The description of the wall given by Walne^2,3 and by Cavalier-Smith⁴ is essentially similar to that given by Sager and Palade. Barnett and Preston⁵ using the freeze etching technique reported the presence of oriented microfibrils in the cell walls. The regular features were interpreted as being cellulose which was thought to be synthesized by small granules associated with the surface of the plasmalemma. In the related species C. moewusii the wall had a regular periodicity of 23.3 nm, and again the striations were interpreted⁶ as being cellulose fibrils, but it was noted that the spacings were smaller than those observed in other structures containing cellulose fibrils⁷.