Thermal lability of membrane proteins of age separated erythrocytes as studied by electron spin resonance spin label technique.

Thermal lability of bovine erythrocyte membrane proteins was studied by electron spin resonance using maleimide spin label. The temperature of the sample during measurements could be varied for the first time between 0 and 60 degrees C with an accuracy of +/- 0.1 degrees C. Our results show that "old" erythrocyte membrane proteins are less stable against thermal denaturation then "young" cells.