Positively charged groups at cell surfaces.

Abstract

AbstractAn attempt was made to identify positively charged amino‐groups at the electrokinetic surfaces of human and mouse erythrocytes, cultured cells derived from a human osteogenic sarcoma, and murine ascites sarcoma 37 cells. Following reactions of these cells with formaldehyde, 2,4,6‐trinitrobenzenesulfonic acid; 2‐chloro‐3,5‐dinitropyridine or 2‐chloro‐3,5‐dinitrobenzoic acid, no consistent change in their electrophoretic mobilities was observed. If a number of positively charged groups commonly associated with proteins had been present at the cellular electrokinetic surface, their reaction with the various reagents would have resulted in an increase in net surface negativity. We therefore conclude that these groups are not present at the surfaces of the cells studied.