(A) Phylogenetic analysis of S gene of 2019-nCoV (Wuhan-Hu-1), bat-SL-CoVZXC21, bat-SL-CoVZXC45, SARS-CoV and other coronaviruses using Neighbor-Joining method. Japan, and one in South Korea, were detected positive for 2019-nCoV. They did not visit the specific seafood market, but might have close contact with some pneumonia patients during their trip in Wuhan, raising the concern of limited human-to-human transmission of 2019-nCoV (http://www.thatsmags.com/china/post/30618/new-coronavirus-spreads-to-over-130-in-china-death-toll-rises). Research scientists have released the full genomic sequence of 2019-nCoV, such as Wuhan-Hu-1 (GenBank, accession no. “type”:”entrez-nucleotide”,”attrs”:”text”:”MN908947″,”term_id”:”1798172431″,”term_text”:”MN908947″MN908947). The phylogenetic analysis revealed that the gene sequence of 2016-nCoV is 89% identical to that of bat SARS-like coronavirus ZXC21 (bat-SL-CoVZXC21, accession no. “type”:”entrez-nucleotide”,”attrs”:”text”:”MG772934.1″,”term_id”:”1369125429″,”term_text”:”MG772934.1″MG772934.1) and ZC45 (“type”:”entrez-nucleotide”,”attrs”:”text”:”MG772933.1″,”term_id”:”1369125417″,”term_text”:”MG772933.1″MG772933.1), and 82% identical to that of KB130015 SARS-CoV Tor2 (“type”:”entrez-nucleotide”,”attrs”:”text”:”JX163927″,”term_id”:”404325885″,”term_text”:”JX163927″JX163927), suggesting that 2019-nCoV also belongs to betacoronavirus Lineage B, but has closer homology to bat-SL-CoVZC45 and bat-SL-CoVZXC21 than SARS-CoV [2] (Figure 1). Both bat-SL-CoV ZC45 and KB130015 ZXC21 were found in Chinese horseshoe bats (Rhinolopus sinicus) in Zhoushan city of Zhejiang Province, China between 2015 and 2017 [3], which can infect suckling rats and cause disease. Given that there were some bats and live animals in the seafood market, 2019-nCoV may be originated from bats or live animals exposure to the materials contaminated with bat droppings in the seafood market or surrounding area. Open in a separate window Number 1. Analysis of the practical domains in 2019-nCoV spike protein and its gene. (A) Phylogenetic analysis of S gene of 2019-nCoV (Wuhan-Hu-1), bat-SL-CoVZXC21, bat-SL-CoVZXC45, SARS-CoV and additional coronaviruses using Neighbor-Joining method. (B) The representative scheme of practical domains in S protein of 2019-nCoV. SP, transmission peptide; NTD, N-terminal website; RBD, receptor-binding website; FP, fusion peptide, HR1, heptad repeat 1; HR2, heptad repeat 2; TM, transmembrane website; CP, cytoplasmic website. (C) The prospective sites in 2019-nCoV S for development of vaccines, antibodies and fusion/entry inhibitors. The quick identification of this novel coronavirus is definitely attributed to recent improvements in the detection of respiratory disease illness, including reverse transcription PCR (RT-PCR), real-time reverse transcription PCR (rRT-PCR), reverse transcription loop-mediated isothermal amplification (RT-LAMP), and real-time RT-LAMP as well as multiplex nucleic acid amplification and microarray-based assays [4]. These methods are useful for detecting novel coronaviruses not only in humans, but also in animals for recognition of animal reservoir or intermediate sponsor of 2019-nCoV. WHO recommended that if there is no idea about the putative pathogen from your pneumonia outbreak, a pan-coronavirus assay should be utilized for amplification followed by sequencing of the amplicon for characterization and confirmation (https://apps.who.int/iris/bitstream/handle/10665/330374/WHO-2019-nCoV-laboratory-2020.1-eng.pdf). By aligning 2019-nCoV S protein sequence with those of SARS-CoV and several bat-SL-CoVs, we expected the cleavage site for generating S1 and S2 subunits is located at R694/S695 (Number 1). S1 subunit consists of two practical domains, the N-terminal website (NTD) and a receptor-binding website (RBD), both of which are responsible for the binding of the virion to the receptor within the sponsor cell. They also contain several conformational neutralizing epitopes, providing like a target for developing neutralizing antibodies and vaccines [5]. S2 subunit consists of three practical domains, fusion peptide (FP), and heptad repeat (HR) 1 and 2. After binding of RBD in S1 to the receptor, the S2 subunit changes conformation Rabbit Polyclonal to CD302 by inserting the FP into the sponsor cell membrane and association between KB130015 HR1 and HR2 to form six-helical package (6-HB), resulting in the fusion between viral and cellular membranes. The viral genetic materials enter into the sponsor cell through the fusion pore for replication in the cell [5]. A peptide derived from the HR2 website of SARS-CoV S protein (SC-1) can interact with HR1 region in viral S protein to form heterologous 6-HB, resulting in the inhibition of homologous 6-HB formation between KB130015 HR1 and HR2 domains in viral S protein and thus obstructing the viral fusion with the sponsor cell [6]. KB130015 Since 2019-nCoV S-HR2 sequence is 100% identical to that of SARS-CoV, while there are only a few mutations of non-critical amino acids in S-HR1 region, SC-1 peptide is definitely expected to be also effective against 2019-nCoV illness. We have recently designed and manufactured a pan-CoV fusion inhibitor, EK1 peptide, which could inhibit illness of five human being coronaviruses, including SARS-CoV and MERS-CoV, and three bat-SL-CoVs [7]. Intranasal software of EK1 peptide before or after viral challenge, EK1 peptide can guard human being DPP4-transgenic mice from MERS-CoV illness, suggesting its potential.
