Complete genome sequence of an Ebola virus (Sudan species) responsible for a 2000 outbreak of human disease in Uganda

Abstract

The entire genomic RNA of the Gulu (Uganda 2000) strain of Ebola virus was sequenced and compared to the genomes of other filoviruses. This data represents the first comprehensive genetic analysis for a representative isolate of the Sudan species of Ebola virus. The genome organization of the Sudan species is nearly identical to that of the Zaire species, but the presence of a gene overlap (between GP and VP30 genes) and a longer trailer sequence distinguish it from that of the Reston species. As has been observed with other filoviruses, stemloop structures were predicted to form at the 5' end of Ebola Sudan mRNA molecules, and the genomic RNA termini showed a high degree of sequence complimentarity. Comparisons of the amino acid sequences of encoded gene products shows that there is a comparable level of identity or similarity between Ebola virus species, with Sudan and Zaire actually showing a slightly closer relationship to the Reston species than to one another. These comparisons also indicated that the VP24 is the most conserved Ebola virus protein (followed closely by the VP40 and L proteins), while the GP is the least conserved gene product. The most divergent regions were seen in the C-terminus of GP1 (mucin-like region) and within the C-terminal third of the nucleoprotein sequence.