Membrane proteins of incubated erythrocytes: effect of sulphydryl inhibition.

Incubation of erythrocytes with various sulphydryl inhibitors for 24 h leads to an accumulation in isolated membranes of globin as well as an unidentified polypeptide of apparent molecular weight 24 000 on polyacrylamide gel electrophoresis. Accumulation of both these components does not appear to be directly related to erythrocyte adenosine triphosphate and reduced glutathione levels. The 24 000 molecular weight polypeptide is probably derived from the erythrocyte cytosol, as determined by polyacrylamide gel electrophoresis of the non-haemoglobin proteins of the cytosol. Together with globin it forms an integral part of the 'spectrin-actin lattice' of sulphydryl-inhibited erythrocytes, as both these components can be detected, together with spectrin and actin, after extraction of such membranes by Triton X-100. We postulate that this leads to inherent damage and distortion to the membranes of such erythrocytes.