Artificial assembly of envelope particles of HVJ (Sendai virus)

The upper HA band fraction of HVJ was isolated by the method as described in the previous report and mixed with lipids in the presence of Nonidet P40 and dialyzed against PBS, and formed active hemolysins appeared large membranous particles of more than 600 A with spikes.

Abstract

The upper HA band fraction of HVJ was isolated by the method as described in the previous report (Hosaka and Shimizu, 1972) and mixed with lipids in the presence of Nonidet P40 and dialyzed against PBS. In this system, lipid components permitting formation of the active hemolysins were investigated. When the four major phospholipid components of HVJ were used separately, phosphatidylethanolamine was the most effective, phosphatidylcholine and sphingomyelin were effective only at high concentrations, and phosphatidylserine was ineffective. Phosphatidylethanolamine from commercial sources was as effective as that from viral sources. In mixed viral phospholipids, something like cooperative effectiveness was found. A low concentration of cholesterol stimulated the formation of active hemolysins, but a high concentration inhibited it. Cholesterol together with phospholipids seemed to contribute to the rigidity of the membranes. Thus formed active hemolysins appeared large membranous particles of more than 600 Å with spikes. No phospholipase activity was detected in the active hemolysins.