MEMBRANOTROPIC PROPERTIES OF PROTEIN CONJUGATES WITH BLOCK-COPOLYMERSOF ETHYLENE-OXIDE AND PROPYLENE-OXIDE

It was earlier established that conjugates of hydrophilic proteins wit h block copolymers of ethylene oxide and propylene oxide (proxanols) u sed at low concentrations decrease the oxidation of NAD-dependent subs trates in mitochondria and cells. The dependence of this property on t he chemical structure and structural organization of the conjugates ha s been studied. The conjugates have been shown to inhibit the oxygen c onsumption in lymphocytes when the hydrophobic (polypropylene oxide) b locks are located on the periphery of the conjugate and the polymer ch ains form domains that are irregularly distributed on the surface of t he protein globule. The minimum number of the polymer chains in the co njugate sufficient to provide this property is three. Additional evide nce has been obtained indicating that conjugates can penetrate through the cellular membrane of lymphocytes and reach the NADH-dehydrogenase complex located in mitochondria.