Proteins of marsupial erythrocyte membranes.

The proteins of erythrocyte membranes from the red kangaroo, western grey kangaroo, eastern grey wallaroo (euro), red-necked wallaby, Tammar wallaby, and brush-tail possum have been fractionated on acrylamide gels in the presence of sodium dodecyl sulfate. The pattern of proteins was remarkably similar between the different marsupial species. The pattern of Coomassie blue-staining proteins in the membranes of these species was also very similar to that of the human erythrocyte membrane. However, the glycoproteins in the marsupial erythrocyte membranes were markedly less conspicuous than those of the human erythrocyte membrane. Furthermore, the mobilities of the glycoproteins from the marsupials were different from those of the human erythrocyte membrane. The erythrocytes of the western grey kangaroo, the eastern wallaroo and the red-necked wallaby showed pronounced resistance to hypotonic lysis compared with those of the Tammar wallaby and the human. This effect seems to be related to the size of the erythrocytes rather than to differences in their protein composition.