Detergents Linked to Polysaccharides: Preparation and Effects on Membranes and Cells

Abstract

Residues of Triton X‐100 [C8H17‐C6H4‐(O‐CH2‐CH2)9‐10‐O‐] were bound by ether bonds to inulin, dextran, amylose, and cellulose‐yielding compounds containing 10–30, 5, 19 and 6% (w/w) of Triton X‐100 residue respectively. The water‐soluble inulin derivative was studied in detail. This compound was fractionated on the basis of molecular weight by gel chromatography and on the basis of degree of substitution by adsorption to polystyrene resin. Even the residues of Triton X‐100 which were bound to a single inulin macromolecule were able to form a micelle; in addition to these monomolecular micelles the inulin derivative was able to form polymolecular micelles as well. The inulin derivative was effective in solubilizing proteins and phospholipids from membranes of human erythrocytes and liberated reverse transcriptase activity from the membrane‐enveloped virions of murine leukemia. The Triton X‐100 inulin derivative abolished binding of the 3H‐labelled antagonist dihydroalprenolol to solubilized preparations of β‐adrenergic receptors from frog erythrocytes in a dose‐related manner similar to the inactivation produced by Triton X‐100, while digitonin, a detergent containing a bulkier hydrophobic group, did not cause inactivation. On the basis of its Triton X‐100 content, the inulin derivative was found to be less detrimental to the growth of murine erythroleukemic cells in vitro than Triton X‐100 alone when short (2–4 h) exposures were used, but this difference disappeared at longer (1–3 day) exposures. Results thus suggest that the increase in size of the hydrophilic part of the detergent brings about moderation in those effects of the detergent which are dependent on the rate of diffusion, while the solubilizing and inactivating effects of the detergent were not changed. It is probably the size of the hydrophobic part which is important in protein‐inactivating properties of the detergent. Copyright © 1979, Wiley Blackwell. All rights reserved