The first complete genome sequence of a non-chicken aviadenovirus, proposed to be turkey adenovirus 1

The complete genome sequence of an adenovirus, isolated from turkey and proposed to be turkey adenovirus type 1 (TAdV-1), was determined to extend our knowledge about the genome organisation and phylogeny of aviadenoviruses. The longest adenovirus genome, consisting of 45,412 bp, with the highest G + C content (of 67.55%) known to date, was found. The central part of the TAdV-1 genome has the conserved gene set and arrangement that are characteristic for every other adenovirus analysed to date. This genome core is flanked by the terminal early regions 1 and 4 (E1 and E4). Aviadenovirus-specific genus-common genes were found in these regions, each containing nine such open reading frames (ORFs). Additionally a type-specific novel ORF, designated as ORF50, was found in E4. Phylogenetic analysis as well as the presence of the genus-specific genes, splice sites and protease cleavage sites confirmed the classification of TAdV-1 in the genus Aviadenovirus. Intrageneric analyses of two genus-specific genes demonstrated the distinctness of TAdV-1 from other aviadenoviruses, thus supporting the proposal for the establishment of a new species, Turkey adenovirus B for TAdV-1.