Psittacine Beak and Feather Disease Virus Nucleotide Sequence Analysis and Its Relationship to Porcine Circovirus, Plant Circoviruses, and Chicken Anaemia Virus

Abstract

Cloning and sequencing of the circular, single-stranded DNA of one isolate of psittacine beak and feather disease virus (BFDV) demonstrate a genome composed of a circular molecule of 1993 nucleotide bases. An analysis of the assembled replicative form demonstrated seven open reading frames (ORFs) (three in the virion strand and four in the complementary strand), potentially encoding seven viral proteins of >8.7 kDa. High amino acid sequence similarity was demonstrated between a potential 33.3-kDa protein product of ORF1 of BFDV and the replicase-associated protein of porcine circovirus (PCV), subterranean clover stunt virus, and faba bean necrotic yellows virus. However, significant similarity in nucleotide or amino acid sequences was not present between BFDV and chicken anaemia virus. A potential stem-loop structure similar to that found in PCV and plant circoviruses was present in the putative encapsidated strand of the BFDV genome. At the top of this structure, a nonanucleotide motif (TAGTATTAC) similar to that of PCV, plant circoviruses, and geminiviruses also was recognised. Comparison of the deduced amino acid sequences of ORF2 of BFDV and PCV demonstrated 29.1% identity, and in both viruses, ORF2 is located on the complementary strand, beginning close to or within the hairpin stem. Our findings provide further evidence of a close relationship among BFDV, PCV, and plant circoviruses but not chicken anaemia virus.

Pigeon circovirus infection: Pathological observations and suggested pathogenesis

“…CAV, PBFD virus and porcine circovirus. Yet recent DNA cloning and sequencing studies have described striking similarities between porcine circovirus and Pigeon circovirus infection 155 PBFD virus genomes (Niagro et al, 1998), whereas no such homologies were found when these two viruses were compared with CAV (Bassami et al, 1998). The pigeon circovirus has been described as antigenically distinct from PBFD virus, although possible homologous DNA sequences, as demonstrated by DNA in situ hybridization, have been found between both viruses (Woods et al, 1994).…”

“…Circoviruses are tiny non-enveloped icosahedral viruses (15-24 nm in diameter) with a single-stranded circular DNA of 1.76 kb to 2.31 kb (Bassami et al, 1998;Niagro et al, 1998). Like most other members of the newly proposed Circoviridae family, PiCV is characterized by typical basophilic globular inclusions in light microscopy (Woods et al, 1993;Shivaprasad et al, 1994;Woods et al, 1994).…”

Comparitive sensitivity of polymerase chain reaction diagnosis of psittacine beak and feather disease on feather samples, cloacal swabs and blood from budgerigars (Melopsittacus undulates, Shaw 18005)

“…Virus detection in live birds can be achieved by haemagglutination using erythrocytes from goffin cockatoos, guinea pigs or galahs (Ritchie et al, 1991;Raidal et al, 1993). The determination of the complete nucleotide sequence of BFDV was the basis for establishment of molecular detection methods, especially polymerase chain reaction (PCR) (Ritchie et al, 1989;Bassami et al, 1998Bassami et al, , 2001. Ypelaar et al (1999) tested several primer combinations that hybridized with various regions of the genome.…”

Duplex Shuttle PCR for Differential Diagnosis of Budgerigar Fledgling Disease and Psittacine Beak and Feather Disease

“…It carries single-stranded circular DNA with a complete genome size of about 2 kb (2,18,32). PBFDV is a member of the genus Circovirus in the family Circoviridae (1,18).…”