Аннотация:Cloned laboratory mutants of herpes simplex virus type I resistant to acycloguanosine H-phosphonate have been investigated. For all clones were shown that mutations resulted to increasing of sensitivity to acting of sidofovir. Thymidine kinase of mutant viruses partially preserves the ability to phosphorilate thymidine, but loses the ability to phosphorilate BVDU.