Grooves in the Plasmalemma of Saccharomyces Cerevisiae Seen in Glancing Sections of Double Aldehyde-fixed Cells

Grooves on the surface of the plasmalemma(plasma membrane) of frozen-etched yeast cells have been shown by many investigators (1, 10, 12) . Necas et al. (13) showed interconnected grooves on the surface of frozen-etched Saccharomyces cerevisiae protoplasts, but such structures could not be so effectively demonstrated in frozen-etched protoplasts prefixed in glutaraldehyde . Structures comparable to these grooves have not been demonstrated in thin sections of chemically fixed whole cells of yeast . Darling et al . (3) reported cleft-like invaginations in tangential sections of S. cerevisiae protoplasts. Ludvik et al . (8) showed deep indentations in cross-sections of plasmalemma of Candida lipolytica grown on hydrocarbon . In this note I am presenting my observation that by a double aldehyde fixation procedure after Karnovsky (6), numerous grooves can be demonstrated in the plasma membrane of the stationary phase cells of S . cerevisiae .