Nucleotide sequence of a 55 kbp region from the right end of the genome of a pathogenic African swine fever virus isolate (Malawi LIL20}1

The nucleotide sequence of a 55 098 bp region from the right end of the genome of a virulent African swine fever virus (ASFV) isolate (Malawi LIL20/1) has been determined. Translation of the sequence identified 67 major open reading frames (ORFs) which are closely spaced and read from both DNA strands. At six positions intergenic tandem repeat arrays are found. Comparison of the predicted amino acid sequences of encoded proteins with protein sequence databases identified a number of homologies. These include three subunits of RNA polymerase, a protein with homology to transcription factor SII (TFSII), a DNA ligase, two subunits of mRNA capping enzyme, a DNA topo-isomerase type II, a dUTPase, a protein kinase, three helicases, a ubiquitin-eonjugating enzyme, a protein with homology to the n/f S and n/f S-like proteins identified in some bacteria nd Saccharomyces cerevisiae, a protein with homology to both a myeloid differ-entiation primary response antigen (MyDll6) and to a herpes implex virus-encoded neurovirulence-associated protein (ICP34.5), a protein with homology to the ASFV-encoded structural protein p22, two proteins with homology to copies of the ASFV-encoded multigene family 360 and one protein with homology to the ASFV-encoded multigene family 110. Four genes encode proteins which have homology to each other and constitute a new multigene family (MGF100). Nine ORFs encode proteins which contain predicted trans-membrane domains. The possible functions of these predicted ASFV-encoded proteins are discussed and the evolutionary relationship of ASFV to other viruses are considered. Despite the similarities in genome structure and replication strategy of ASFV with pox-viruses, sequence similarity between them is low and the organization of ASFV-encoded genes is not colinear with that of the orthopoxviruses