Structural analysis of the capsid polypeptides of herpes simplex virus types 1 and 2

Abstract

Capsids of herpes simplex virus (HSV) types 1 and 2 contain 7 polypeptides ranging in MW from 154,000-12,000 (termed NC-1 through NC-7 in order of descending MW). Antibodies prepared to HSV-1 capsid polypeptides isolated from sodium dodecyl sulfate-polyacrylamide gels reacted in an immunofluorescence assay against HSV-1-infected KB [human oral carcinoma] cells. Three antibodies (anti-NC-1, anti-NC-2 and anti-NC-3,4) also reacted with HSV-2-infected cells. Tryptic peptide analysis showed that each HSV-1 capsid polypeptide had a unique methionine peptide profile and none appeared to be derived from the major capsid polypeptide. Comparative peptide analysis of HSV-1 and HSV-2 showed that 1 polypeptide (NC-7, 12,000 MW) had an identical methionine peptide profile and a very similar arginine peptide profile in both virus types. The arginine peptide profile of NC-7 of HSV-1 was very different from the arginine profile of KB histone H4. There were certain intertypic similarities in the methionine peptide profiles of the other capsid components, especially in NC-1 (the major capsid protein), but there was no case where the tryptic peptides were identical in the 2 virus types.