Woo Patrick C Y, Lau Susanna K P, Tsoi Hoi-Wah, Patteril Nissy Georgy, Yeung Hazel C, Joseph Sunitha, Wong Emily Y M, Muhammed Rubeena, Chow Franklin W N, Wernery Ulrich, Yuen Kwok-Yung
Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong SAR.
State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong SAR.
J Gen Virol. 2017 Jun;98(6):1349-1359. doi: 10.1099/jgv.0.000775. Epub 2017 Jun 14.
The recent emergence of Middle East respiratory syndrome (MERS) coronavirus and its discovery from dromedary camels has boosted interest in the search for novel viruses in dromedaries. While bocaparvoviruses are known to infect various animals, it was not known that they exist in dromedaries. In this study, we describe the discovery of two novel dromedary camel bocaparvoviruses (DBoVs), DBoV1 and DBoV2, from dromedary faecal samples in Dubai. Among 667 adult dromedaries and 72 dromedary calves, 13.9 % of adult dromedaries and 33.3 % of dromedary calves were positive for DBoV1, while 7.0 % of adult dromedaries and 25.0 % of dromedary calves were positive for DBoV2, as determined by PCR. Sequencing of 21 DBoV1 and 18 DBoV2 genomes and phylogenetic analysis showed that DBoV1 and DBoV2 formed two distinct clusters, with only 32.6-36.3 % amino acid identities between the DBoV1 and DBoV2 strains. Quasispecies were detected in both DBoVs. The amino acid sequences of the NS1 proteins of all the DBoV1 and DBoV2 strains showed <85 % identity to those of all the other bocaparvoviruses, indicating that DBoV1 and DBoV2 are two bocaparvovirus species according to the ICTV criteria. Although the typical genome structure of NS1-NP1-VP1/VP2 was observed in DBoV1 and DBoV2, no phospholipase A2 motif and associated calcium binding site were observed in the predicted VP1 sequences for any of the 18 sequenced DBoV2, and no start codons were found for their VP1. For all 18 DBoV2 genomes, an AT-rich region of variable length and composition was present downstream to NP1. Further studies will be crucial to understand the pathogenic potential of DBoVs in this unique group of animals.
中东呼吸综合征（MERS）冠状病毒的近期出现以及从单峰骆驼中发现该病毒，激发了人们在单峰骆驼中寻找新型病毒的兴趣。虽然细小病毒已知可感染多种动物，但此前并不清楚它们存在于单峰骆驼中。在本研究中，我们描述了从迪拜单峰骆驼粪便样本中发现两种新型单峰骆驼细小病毒（DBoV），即DBoV1和DBoV2。在667头成年单峰骆驼和72头单峰骆驼幼崽中，经PCR检测，13.9%的成年单峰骆驼和33.3%的单峰骆驼幼崽DBoV1呈阳性，而7.0%的成年单峰骆驼和25.0%的单峰骆驼幼崽DBoV2呈阳性。对21个DBoV1和18个DBoV2基因组进行测序及系统发育分析表明，DBoV1和DBoV2形成两个不同的簇，DBoV1和DBoV2毒株之间的氨基酸同一性仅为32.6 - 36.3%。在两种DBoV中均检测到准种。所有DBoV1和DBoV2毒株的NS1蛋白氨基酸序列与所有其他细小病毒的氨基酸序列同一性均低于85%，这表明根据国际病毒分类委员会（ICTV）的标准，DBoV1和DBoV2是两种细小病毒物种。尽管在DBoV1和DBoV2中观察到典型的NS1 - NP1 - VP1/VP2基因组结构，但在18个测序的DBoV2的预测VP1序列中，未观察到磷脂酶A2基序和相关的钙结合位点，且未发现其VP1的起始密码子。对于所有18个DBoV2基因组，在NP1下游存在一个长度和组成可变的富含AT的区域。进一步的研究对于了解DBoV在这一独特动物群体中的致病潜力至关重要。
