Involved in countering a host defense mechanism which, following viral infection, activates the host induced anticodon nuclease and shuts off viral translation. Repairs 5'-PO4 and 3'-OH groups in the cleaved host tRNA. Optimum activity is reached at 1 mM and 5 mM for Mn(2+) and Mg(2+) respectively, with Mn(2+) showing 90% of the Mg(2+) activity. Optimum pH is 7. Optimum temperature is 64 degrees Celsius.