The effect of ammonium chloride and tunicamycin on the glycoprotein content and infectivity of herpes simplex virus type 1

Infectious virions of MP, a syncytial strain of herpes simplex virus type 1, are formed in the presence of 50 m M NH 4Cl. Underglycosylated virion glycoproteins are synthesized in infected cells and are incorporated into virions in the presence of the same concentration of NH 4Cl. We conclude that fully glycosylated glycoproteins are not required for viral infectivity. Virus particles, deficient in glycosylated glycoproteins, are assembled in the presence of tunicamycin but they are not infectious. The decrease in infectivity could be due to the decreased amount of the gB or possibly other peptides and/or to the lack of the high-mannose saccharides of precursor glycoproteins.