对于犬细小病毒2型(CPV-2),一种能够在动物中跨物种传播的人畜共患病毒,衣壳蛋白VP2的氨基酸变化是与其他物种转铁蛋白受体(TfR)结合时的关键因素。CPV-2变体可以从猫科动物和犬科动物传播,例如,食肉,偶蹄,和Pholidota物种,和CPV-2c变体对于从食肉动物传播到偶蹄动物和Pholidota物种至关重要。在我们的研究中,CPV-2a变体保持相对稳定的趋势,从1980年到2021年,CPV-2c的比例逐渐上升。VP2氨基酸序列分析表明,5个氨基酸在426E/D发生突变,305H/D,和297S可能是病毒结合不同宿主受体所必需的。同时,受体结合环区和氨基酸位点87L,93N,232I,305Y与CPV-2跨物种传播有关。感染CPV-2的不同宿主中TfRs的同源性为77.2%~99%,从猪到猫,犬,人类占80.7%,80.4%,77.2%,分别。在这些宿主中参与病毒结合的TfRs的氨基酸残基是高度保守的,这表明CPV-2可能能够在猪到人之间传播。我们对起源的分析,进化趋势,跨物种传播动力学,CPV-2与宿主受体结合时的遗传特性为进一步研究CPV-2的跨物种传播机制以及建立CPV-2可能威胁动物-人类公共安全的预警和监测机制提供了理论依据。
For canine parvovirus -2 (CPV-2), a zoonotic virus capable of cross-species transmission in animals, the amino acid changes of capsid protein VP2 are key factors when binding to other species\' transferrin receptors (TfR). CPV-2 variants can spread from felines and canines, for example, to Carnivora, Artiodactyla, and Pholidota species, and CPV-2c variants are essential to spread from Carnivora to Artiodactyla and Pholidota species in particular. In our study, a CPV-2a variant maintained a relatively stable trend, and the proportion of CPV-2c gradually rose from 1980 to 2021. The VP2 amino acid sequence analysis showed that five amino acid mutations at 426E/D, 305H/D, and 297S may be necessary for the virus to bind to different host receptors. Meanwhile, receptor-binding loop regions and amino acid sites 87 L, 93 N, 232I, and 305Y were associated with CPV-2 cross-species transmission. The homology of TfRs in different hosts infected with CPV-2 ranged from 77.2 % to 99.0 %, and from pig to feline, canine, and humans was 80.7 %, 80.4 %, and 77.2 %, respectively. The amino acid residues of TfRs involved in the viral binding in those hosts are highly conserved, which suggests that CPV-2 may be capable of pig-to-human transmission. Our analysis of the origin, evolutionary trend, cross-species transmission dynamics, and genetic characteristics of CPV-2 when binding to host receptors provides a theoretical basis for further research on CPV-2\'s mechanism of cross-species transmission and for establishing an early warning and monitoring mechanism for the possible threat of CPV-2 to animal-human public security.