Identification and sequencing of the Choristoneura biennis entomopoxvirus DNA polymerase gene.

A degenerate oligonucleotide probe corresponding to a highly conserved amino acid sequence in several DNA polymerases was used to locate the DNA polymerase gene in the Choristoneura biennis entomopoxvirus. Southern blot analysis of the entomopoxvirus genome using the degenerate oligonucleotide probe showed specific interaction between the probe and an eight kilobasepair EcoRI fragment from the entomopoxvirus genome. Sequencing this EcoRI fragment revealed an open reading frame 2892 nucleotides in length, capable of encoding a protein about 115 kilodaltons. Homology search of this open reading frame against other proteins indicated a high degree of homology in four distinct regions with DNA polymerases from other organisms. The highest degree of homology (24.9% at the amino acid level) was found between the vaccinia DNA polymerase gene and the entomopoxvirus open reading frame.