Molecular characterization of nobecovirus in cave nectar bat

Abstract

[Scientific] The interest in the research on coronaviruses (CoV) has been raised since the global outbreak of Severe Acute Respiratory Syndrome (SARS) in 2003, and later findings indicated that bats were not only the original reservoir of SARS-CoV, but also a major reservoir of multiple CoVs. As a result, investigations in bat CoV have surged intensively in order to explore potential zoonotic risk. Due to rapid mutation within the family of CoV, frequent recombination has been found in CoV to enhance its host adaptability and facilitate the rate of transmission. In 2016, a novel betaCoV, Rousettus BatCoV GCCDC1 (Ro-BatCoV GCCDC1), was discovered as a crossfamily recombination of CoV and a Reovirus gene. Previously, limited data in Genbank left a blank in the relationship between this virus and its bat host species and, consequently, the history of this viral development. This study provided an additional genome of BatCoV GCCDC1 extracted from Eonycteris spelaea (Eo- BatCoV GCCDC1), allowing for the first investigation in genomic-structural comparison between Ro-BatCoV GCCDC1 and Eo-BatCoV GCCDC1, as well as phylogenetic analyses with all available strains of BatCoV GCCDC1 in Genbank, to be accomplished. The results showed that Eo-BatCoV GCCDC1 shared more than 96% nucleotide identity with Ro-BatCoV GCCDC1. Both share a homogeneous genomic structure with the Reovirus gene. Besides, their spike proteins are highly identical in amino acid residues with one deviation among each estimated conserved domain. Although this study furthered understanding in the history of BatCoV GCCDC1, continued investigation and expansion of Genbank data would still be needed to explore viral transmission routes and detect any functional deviation among various host species to achieve a more precise evaluation in the zoonotic risk. [Laymen] Virus is a pathogen infecting many living organisms and can be further classified into the family, order, genera, subgenera, and species. Coronavirus (CoV) is a large group of viruses in the family of Coronaviridae, the order of Nidovirale, in which, Severe Acute Respiratory Syndrome (SARS)-CoV and Middle East Respiratory Syndrome (MERS)-CoV are the most well-known viral species that caused the pandemics in 2003 and 2013 respectively. The interest in the research on CoV has been raised since the global outbreak of SARS in 2003, and later findings indicated that bats were not only the original host of SARS-CoV, but also a major host of multiple CoVs. As a result, investigations in bat CoV have surged intensively in order to explore potential zoonotic risk. In 2016, a novel bat CoV was discovered in a Rousettus bat and named as Rousettus BatCoV GCCDC1 (Ro-BatCoV GCCDC1). This viral species was also detected in different bat species such as Eonycteris bat (also named as Cave Nectar bat). This study provided the same viral species extracted from Cave Nectar bat, named Eo-BatCoV GCCDC1, allowing the first investigation in the genomic-structural comparison between Ro-BatCoV GCCDC1 and Eo-BatCoV GCCDC1. Further understanding of the relationship between this virus and its bat host, as well as estimation in the history of this viral development, are also included. The results showed that both Ro-BatCoV GCCDC1 and Eo-BatCoV GCCDC1 were identical in genomic structure and highly similar in protein sequences. Although this study furthered understanding in the history of BatCoV GCCDC1, continued investigation and expansion of genetic data would still be needed to explore viral transmission routes and detect any deviation among various bat species to achieve a more precise evaluation in the zoonotic risk.