Canine CoV-II (CCoV-II) appears to have evolved from recombination events between CCoV-I and an unknown CCoV, resulting in the progressive loss of orf3 in the CCoV-II genome [15,94]. our understanding of SARS-CoV-2, and accordingly, benefit the development of effective control and prevention strategies against COVID-19. (order that consists of four genera: [26]. The alphacoronaviruses and betacoronaviruses infect mammals and include important pathogens of livestock and Cefotiam hydrochloride companion animals (Physique 1, Table 1) [13,24]. On the other hand, the gammacoronaviruses and deltacoronaviruses have been mostly detected in avian species, although there are some reports from mammals, including detection of a gammacoronavirus in a beluga whale (Physique 1, Table 1) [13,24,27]. Open in a separate window Physique 1 Neighbor-net phylogenetic grouping of representative animal and human coronaviruses (CoVs). Blue, yellow, green, and rose circles indicate the genus (subgenera (subgenera = 78) of the spike protein encoding genes of human and animal CoVs were retrieved from the NCBI GenBank portal (https://www.ncbi.nlm. nih.gov/genbank/) and subjected to multiple alignment using the ClustalW program embedded in MEGA 7.0 software. The resultant alignment file was used to generate a neighbor-net phylogenetic tree with the SplitsTree 4.0 program (http://www.splitstree.org/). Table 1 Comparisons of the various features of SARS-CoV-2 with those of coronaviruses (CoVs) in livestock and companion animals. within the subgenus (genus have names derived from the SARS-CoV, which is a reflection of the phylogenetic grouping rather than clinical presentation of the computer virus [25]. Even though SARS-CoV-2 and SARS-CoV belong to the same species and bind to the same receptor (angiotensin converting enzyme II (ACE2)) on host cells, they share low sequence similarity (~79%) between themselves [11,28]. The MERS-CoVs from humans and dromedary camels were assigned to the species constitute the subgenus (Physique 1) [26]. The other two human betacoronaviruses, HCoV-OC43 (species that also includes CoVs detected in alpacas, bovines, dogs, dromedaries, pigs, and rodents (Physique 1) [13,26]. Human alphacoronaviruses HCoV-NL63 and HCoV-229E belong to the subgenera (also including species (genus have been delineated with dark red, blue, green, and pink lines, respectively. The subgenera of CoVs are demarcated with black dashed lines and indicated with italic type. The common names of CoVs are pointed out in parenthesis, and those of human CoVs Cefotiam hydrochloride are highlighted with red font. Abbreviations: BCoVbovine coronavirus; CCoVcanine coronavirus; CRCoVcanine respiratory coronavirus; FCoVfeline coronavirus; FRCoVferret coronavirus; HCoVhuman coronavirus; IBVinfectious bronchitis computer virus; MCVmink coronavirus; MERS-CoVmiddle east respiratory syndrome coronavirus; MHVmouse hepatitis computer virus; PDCoVporcine deltacoronavirus; PEDVporcine epidemic diarrhea computer virus; PHEVporcine hemagglutinating encephalomyelitis computer virus; PRCoVporcine respiratory coronavirus; QCoVquail coronavirus; SADS-CoVswine acute diarrhea syndrome coronavirus; SARS-CoVsevere acute respiratory syndrome coronavirus; TCoVturkey coronavirus; TGEVtransmissible gastroenteritis computer virus. The possible functions of recombination and mutation in the origin and spread of SARS-CoV-2 have been evaluated [11,78]. The SARS-CoV-2 genome shared a maximum nucleotide sequence identity of 96.2% with that of bat CoV strain RaTG13 (from a horseshoe bat [13,91]. Furthermore, BCoVs, thought to be descendants of the rodent CoVs, were hypothesized to be involved in the evolution of non-bovine CoVs, such as canine Rabbit polyclonal to GNRHR respiratory CoVs (CRCoV), porcine hemagglutinating encephalomyelitis computer virus (PHEV), and equine CoVs [13,88,92]. On the other hand, Cefotiam hydrochloride birds are considered as reservoirs of the ancestors of gammacoronaviruses and deltacoronaviruses [13,93]. Recombination and mutation are intimately linked with the evolution of animal CoVs, and have been associated with changes in virulence, tissue tropism, and host specificity [13,14,15,17,18,21,91]. Canine CoV-II (CCoV-II) appears Cefotiam hydrochloride to have evolved from recombination events between CCoV-I and an unknown CCoV, resulting in the progressive loss of orf3 in the CCoV-II genome [15,94]. Furthermore, recombinant CCoV-II strains that are related to prototype TGEV-like strains in the 5- and 3- ends of the S gene, and classified as CCoV-IIb based on the amino acid sequence of.
