Abstract:
Adenoviruses are non-enveloped icosahedral-shaped particles which
possess a double-stranded DNA genome. Currently, nearly 100 serotypes of
adenoviruses have been identified, 48 of which are of human origin. Bovine
adenoviruses (BAVs), causing both mild respiratory and/or enteral diseases in
cattle, have been reported in many countries all over the world. Currently, nine
serotypes of SAVs have been isolated which have been placed into two
subgroups based on a number of characteristics which include complement
fixation tests as well as the ability to replicate in various cell lines. Bovine
adenovirus type 2 (BAV2), belonging to subgroup I, is able to cause pneumonia
as well as pneumonic-like symptoms in calves. In this study, the genome of
BAV2 (strain No. 19) was subcloned into the plasmid vector pUC19. In total, 16
plasmids were constructed; three carry internal San fragments (spanning 3.1 to
65.2%
), and 10 carry internal Pstl fragments (spanning 4.9 to 97.4%), of the viral
genome. Each of these plasmids was analyzed using twelve restriction
endonucleases; BamHI, CiaI, EcoRl, HiOOlll, Kpnl, Noll, NS(N, Ps~, Pvul, Saj,
Xbal, and Xhol. Terminal end fragments were also cloned and analyzed,
sUbsequent to the removal of the 5' terminal protein, in the form of 2 BamHI B
fragments, cloned in opposite orientations (spanning 0 to 18.1°k), and one Pstll
fragment (spanning 97.4 to 1000/0). These cloned fragments, along with two
other plasmids previously constructed carrying internal EcoRI fragments
(spanning 20.6 to 90.5%), were then used to construct a detailed physical
restriction map using the twelve restriction endonucleases, as well as to estimate
the size of the genome for BAV2(32.5 Kbp). The DNA sequences of the early region 1 (E1) and hexon-associated gene (protein IX) have also been
determined. The amino acid sequences of four open reading frames (ORFs)
have been compared to those of the E1 proteins and protein IX from other Ads.
