Characterization of a Novel Porcine Parvovirus Tentatively Designated PPV5

Abstract

A new porcine parvovirus (PPV), provisionally designated as PPV5, was identified in U.S. pigs. Cloning and sequencing from a circular or head-to-tail concatemeric array revealed that the PPV5 possesses the typical genomic organization of parvoviruses with two major predicted open reading frames (ORF1 and ORF2), and is most closely related to PPV4 with overall genomic identities of 64.1–67.3%. The amino acid identities between PPV5 and PPV4 were 84.6%–85.1% for ORF1 and 54.0%–54.3% for ORF2. Unlike PPV4, but similar to bovine parvovirus 2 (BPV2), PPV5 lacks the additional ORF3 and has a much longer ORF2. Moreover, the amino acid sequences of ORF1 and ORF2 of BPV2 showed higher homologies to PPV5 than to PPV4. The conserved motifs of the Ca2+ binding loop (YXGXG) and the catalytic center (HDXXY) of phospholipase A2 (PLA2) were identified in VP1 (ORF2) of PPV5, as well as in BPV2, but were not present in PPV4. Phylogenetic analyses revealed that PPV5, PPV4 and BPV2 form a separate clade different from the genera Parvovirus and Bocavirus. Further epidemiologic investigations of PPV4 and PPV5 in U.S. pigs of different ages indicated a slightly higher prevalence for PPV5 (6.6%; 32/483) compared to PPV4 (4.1%; 20/483), with detection of concurrent PPV4 and PPV5 in 15.6% (7/45) of lungs of infected pigs. Evidence for potential vertical transmission or association with reproductive failure was minimal for both PPV4 and PPV5. The high similarity to PPV4 and the lack of ORF3 may suggest PPV5 is an intermediate of PPV4 during the evolution of parvoviruses in pigs.

Identification and genomic characterization of a novel porcine parvovirus (PPV6) in china

“…These results indicated the presence of a possible novel parvovirus. On the basis of its homology to parvoviruses and its swine host, this DNA virus was tentatively named porcine parvovirus type 6 (PPV6) after the two recently identified PPVs; i.e., PPV4 and PPV5 (data not shown) [12,21]. Attempts to stably passage the PPV in PK15 (swine kidney), Vero (African green monkey kidney), and Marc 145 (fetal rhesus monkey kidney) cells were unsuccessful (data not shown).…”

“…They also differed from other parvoviruses by their relatively large predicted VP protein. These analyses indicated that PPV6 viruses are likely to belong to the novel genus Copiparvovirus within the subfamily Parvovirinae [12]. Pairwise comparisons were performed for the nucleotide sequences and predicted amino acids sequences of PPV6 with other parvoviruses.…”

“…An additional ORF; i.e., ORF3, encodes an accessory protein and has been identified in some parvoviruses, such as NP1, an NSP only found in bocavirus and PPV4 [6,7]. In recent years, with the use of molecular assays and pathogen discovery tools, a number of novel parvoviruses belonging to the subfamily Parvovirinae have been identified in various animal species and humans, including human parvovirus 4 (PARV4), porcine hokovirus (PPV3), ovine partetravirus, PPV4, and PPV5 [6][7][8][9][10][11][12][13]. Among them, PPV3 and ovine partetravirus have been shown to have a close relationship to PARV4, and currently have been proposed to be classified into the genus Tetraparvovirus by the ICTV [3,4].…”

“…Among them, PPV3 and ovine partetravirus have been shown to have a close relationship to PARV4, and currently have been proposed to be classified into the genus Tetraparvovirus by the ICTV [3,4]. In addition, PPV4 and PPV5 were both identified in clinical samples from swine herds, forming a distinct branch with bovine parvovirus 2 (BPV2) based on phylogenetic analysis, which led to consideration of these viruses being classified in a novel genus; i.e., Copiparvovirus [11,12]. Within parvoviruses, six different phylogenetic groups of parvoviruses have been identified from pigs, including classic PPV, PPV2, PPV3, PPV4, PPV5, and porcine bocaviruses (PBoV) [7][8][9][10][11][12].…”

“…In addition, PPV4 and PPV5 were both identified in clinical samples from swine herds, forming a distinct branch with bovine parvovirus 2 (BPV2) based on phylogenetic analysis, which led to consideration of these viruses being classified in a novel genus; i.e., Copiparvovirus [11,12]. Within parvoviruses, six different phylogenetic groups of parvoviruses have been identified from pigs, including classic PPV, PPV2, PPV3, PPV4, PPV5, and porcine bocaviruses (PBoV) [7][8][9][10][11][12]. The reported overall prevalence of parvoviruses in pig herds has varied from 6.4% to 20% for PPV2, 9.7% to 12.4% for PPV3, 1.5% to 39.7% for PBoV, and 2.6% to 6.6% for PPV5 [14][15][16][17].…”