AFRICAN SWINE FEVER VIRUS THYMIDYLATE KINASE GENE - SEQUENCE AND TRANSCRIPTIONAL MAPPING

A putative thymidylate kinase gene of African swine fever virus has be en identified at the left end of the SalI I' fragment of the virus gen ome. The gene, designated A240L, has the potential to encode a protein of 240 amino acids with an M(r) of 27 754 and is transcribed early af ter infection. Primer extension analysis indicates that transcription is initiated a short distance from the first ATG codon of open reading frame A240L. The deduced amino acid sequence of this open reading fra me shows significant similarity with the human, yeast and vaccinia vir us thymidylate kinases, the degree of identity being 23.7, 25 and 23.5 %, respectively. The putative African swine fever virus thymidylate k inase sequence is essentially collinear with the other thymidylate kin ase sequences, but contains a carboxy-terminal extension of 37 amino a cids rich in glutamic and aspartic acids. The A240L protein conserves the ATP-binding and nucleotide/nucleoside-binding domains characterist ic of thymidylate kinases.