Structural analogy among mammalian spectrins and spectrin-like proteins revealed by molybdenum labeling.

Pentavalent complex of 99Mo with ascorbic acid binds in vitro to the plasma membranes of human, rabbit, rat and mouse red cell membranes and to bovine synaptic and rat intestinal brush border membranes. Red cell spectrins and spectrin-like proteins from non-erythroid cells were determined as the molybdenum-binding proteins in the membranes. Specificity of this binding among all membrane proteins suggests structural analogy in this group of proteins.