Distinctive properties of thymidine kinase isozymes induced by human and avian hepresviruses.

Abstract

AbstractBiochemical and immunological experiments have been performed to learn whether human and avion herpesvirus‐induced dT kinases could be distinguished from the cytosol and mitochondrial dT kinase isozymes of uninfected cells. The dT kinases induced by human herpes simplex virus types 1 and 2 (HSV‐1 and HSV‐2) and by avian infectious laryngotracheitis virus (ILTV) and herpesvirus of turkeys (HVT) were used. The present experiments extend previous investigations and demonstrate that: (1) human and avian herpesvirus‐induced dT kinases differ from cytosol dT kinases of uninfected cells with respect to electrophoretic mobility, isoelectric point and phosphate donor specificity; (2) human and avian herpesvirus‐induced dT kinases differ from mitochondrial dT kinases of uninfected cells with respect to sedimentation coefficients and sensitivity to dCTP inhibition; and (3) HSV‐1‐ and HSV‐2‐induced dT kinases differ from human cytosol and mitochondrial dT kinases in thermal lability and antigenic determinants. The cellular and the viral‐induced dT kinase isozymes were all inhibited by the end product inhibitor, dTTP. Immunoglobulin (Ig) from sera of rabbits immunized with the HSV‐1‐induced dT kinase inhibited the homologous enzyme and some anti‐type 1 Ig preparations partially inhibited the HSV‐2 dT kinase, but the anti‐type 1 Ig inhibited neither cytosol and mitochondrial dT kinases from human, mouse, and monkey cells, nor the dT kinases induced by ILTV, HVT, or vaccinia virus. Anti‐type 2 Ig inhibited the homologous HSV‐2 dT kinase, but not HSV‐1 or human mitochondrial dT kinase.