[The nature of the influenza C virus receptor and the specificity of the receptor-destroying enzyme]

Abstract

Bacterial neuraminidases destroy influenza C virus receptors of chick erythrocytes and inactivate hemagglutination inhibitors: rat alpha 1-macroglobulin (RMG) and bovine submaxillary mucin (BSM). These data indicate that neuraminic acid may be a component of influenza C virus receptor. The inhibiting activity of RMG and BSM is also eliminated by the receptor-destroying enzyme (RDE) of influenza C virus. After inactivation, the inhibitors (RMG and BSM) contain a reduced amount of N-acetyl-9-0-acetylneuraminic acid (Neu5, 9Ac2) and a larger amount of N-acetylneuraminic acid (Neu5 Ac). Transformation of Neu5, 9Ac2 into Neu5 Ac may also occur upon incubation of free neuraminic acid with influenza C virus. These data indicate that the RDE of influenza C virus is neuraminate-O-acetylesterase (N-acyl-9 4-O-acetylneuraminate O-acetylhydrolase (EC 3.1.1.53). It was shown that inhibition of influenza C virus hemagglutination by RMG and BSM and, apparently, adhesion of the virus to the cell surface involves binding of influenza C virus with Neu5, 9Ac2.