Isolation and Characterization of Profilactin and Profilin from Calf Thymus and Brain

1 Profilactin and profilin have been purified from calf thymus and calf brain. Thymus profilactin could be crystallized with a similar technique as described earlier for the spleen protein. 2 Preparations of profilactin from the three calf tissues spleen, thymus and brain contain a mixture of β actin and γ actin. The ratio β/γ differs between the tissues, but is constant throughout the purification steps. 3 The properties of profilin isolated from three sources (spleen, thymus and brain) indicate that it is a highly conserved protein.