DNA structure, and hemagglutination properties of bovine adenovirus type 2 strains which bypass species specificity

Abstract

Bovine adenovirus type 2 (Ad bos 2) strains were examined which had been isolated during natural outbreaks among calves, and lambs in Hungary [Belák, S., Pálfi, V.: Arch. ges. Virusforsch. 46,366-369 (1974)]. Differences were detected in hemagglutination properties, and in the restriction site maps of the DNA, which seem to be sufficient to group isolates of Ad bos 2 into two subtypes (subspecies). Some of the strains, recovered from cattle including prototype strain No. 19 are suggested to be separated as subtype A. These viruses hemagglutinate bovine red blood cells, and the physical map of the DNA is similar to, or identical with that of the prototype strain. Virus strains tentatively grouped into subtype B are pathogenic for both cattle, and sheep under natural conditions. Members of subtype B hemagglutinate only rat erythrocytes, and characteristic differences may be detected with BamHI, EcoRI, KpnI, and SalI restriction endonucleases in comparison to the physical maps of the DNA of prototype virus. The genome size of all isolates tested was measured to be of Mr 19.5 to 20.0 X 10(6), similar to Ad ovi 1, 4, and Ad bos 4, and 6. All isolates of subtype B characteristics were shown to encapsidate heterogeneous genome populations which could be distinguished from those of subtype A by the presence of specific restriction endonuclease cleavage fragments with molar ratios of less than 1.0.

Subcloning and Restriction Enzyme Mapping of Bovine Adenovirus Type 2

“…During this study, four EcoKl fragments and two BamHl fragments were observed as was similarly reported by Benko et al [5] and Belâk et al [3,4], The positions of these frag ments on the linear map were identical to that reported by Belâk et al [4]. The average sum of the restriction fragments generated in this study was 32.5 kbp (table 1).…”

“…Differences in total genomic size may be due to strain differences rather than variations in accuracy of fragment size determination. However, neither Benko et al [5] nor Belak et al [3,4] reported the presence of the terminal ends containing the 5' terminal proteins.…”

“…Î ----------------------- al. [3]. Differences in total genomic size may be due to strain differences rather than variations in accuracy of fragment size determination.…”

“…Subspecies A refers to those isolates of BAV2 with the same charac-teristics as the prototype strain (strain No. 19), whereas subspecies B includes those viruses which are similar to ORT-III, a strain of BAV2 originally isolated from sheep [3].…”

“…Its genome consists of approximately 30.3 to 34.8 kbp in a linear double-stranded DNA molecule [3][4][5] and appears to cause pneumonia as well as pneumonic-like symptoms in cattle [6], Although, generally, most adenoviruses have a narrow host range, there have been several reported cases in which BAV2 strains, similar to the prototype strain (No. 19), have been isolated from sheep [7,8].…”