Abstract
The effect of tunicamycin (TM), a nucleoside antibiotic, known to inhibit growth of a number of virus, protozoan and metazoan organisms, presumably by intervening in the glycosylation of glycoproteins, has been studied on Limnaea egg cells and rabbit erythrocytes. TM decreases the adhesion of cells in Limnaea morula and, apparently, induces a high degree of membrane permeability probably leading to the extrusion of cytoplasmic material. The effect of TM is more specific on mature rabbit erythrocytes which have no subcellular structure. TM treatment in vitro alters the normal biconcave disc-shaped erythrocytes successively into crenated discs, crenated spheres, and smooth spheres. This type of transformation is known to be caused by a number of substances but the present report is the first to indicate a nucleoside-containing compound. This irreversible reaction may be attributed to a structural change of the cellular membrane of erythrocytes.