DIVALENT METALS OF MYELIN AND THEIR DIFFERENTIAL BINDING BY MYELIN BASIC-PROTEIN OF BOVINE CENTRAL-NERVOUS-SYSTEM

Divalent metal ions are being implicated in the compaction of myelin. Levels of Cd, Co, Cu, Hg, Mn, Pb, Zn, Ca and Mg of isolated myelin of bovine central nervous system (CNS) were measured by flame atomic abso rption spectrophotometry. Binding of these metal ions by isolated myel in basic protein (MBP, Mr 18,500) of bovine CNS was concurrently asses sed by centrifugal equilibrium dialysis. Metals were bound in the orde r of Hg > Cu > Zn > Mg > Cd > Co, exempting Mn, Pb and Ca. The results are indicative of differential metal affinity of MBP which may accoun t for the immobilization or anchoring of MBP in myelin by zinc and oth er divalent metal cations.