Partial covalent labeling with pyridoxal 5'-phosphate induces bis(sulfosuccinimidyl)suberate crosslinking of band 3 protein tetramers in intact human red blood cells.

Partial covalent labeling of band 3 protein lysines with pyridoxal 5'-phosphate (a substrate and affinity probe) changes the bis(sulfosuccinimidyl)suberate crosslinking pattern of band 3 in intact red cells from a mixture of dimers and tetramers to all tetramers as the exclusive crosslinked product. This is the first demonstration of band 3 crosslinkage to the tetrameric level within membranes of intact red cells. The possible implications of the ligand-induced change in the band 3 crosslinking pattern are discussed.