LitCovid-sentences  

PMC:7205724 / 3993-9529 JSONTXT 25 Projects

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Id Subject Object Predicate Lexical cue
T39 0-103 Sentence denotes 3.1 SARS-CoV2 has acquired an S glycoprotein that highly underwent genetic variation and glycosylation
T40 105-135 Sentence denotes 3.1.1 Polybasic cleavage site
T41 136-307 Sentence denotes As evidenced by sequence analysis, there is a residue insertion formed of four amino acids (12 nucleotides) at the boundary between S1 and S2 subunits of the SARS-CoV 2 S.
T42 308-510 Sentence denotes It defines a polybasic furin cleavage site of RRAR for the human SARS-CoV 2 that was absent in human SARS-CoV, bat SARS-like CoVs, and pangolin SARS-like CoV while might be present in other species [3].
T43 511-661 Sentence denotes After the introduction of mutation to the residue insertion and furin cleavage site, the S1/S2 cleavage of the SARS-CoV 2 S did not longer take place.
T44 662-772 Sentence denotes However, the SARS-CoV 2 S entry raised for VeroE6 cells and remained high in BHK cells that express human ACE.
T45 773-863 Sentence denotes Therefore, it seems that SARS-CoV2 transmissibility does not depend on the S1/S2 cleavage.
T46 864-989 Sentence denotes A polybasic cleavage site explains a virus that is highly-pathogenic for humans while it is low-pathogenic for other species.
T47 990-1138 Sentence denotes For example, using reverse genetic tools, an avian paramyxovirus type 7 (APMV-7) was developed by mutating the fusion (F) protein cleavage site [4].
T48 1139-1251 Sentence denotes The constructed APMV-7 showed furin cleavage and increased replication and syncytium formation in cell cultures.
T49 1252-1316 Sentence denotes However, chicken exposed to the virus did not exhibit infection.
T50 1318-1338 Sentence denotes 3.1.2 Glycosylation
T51 1339-1509 Sentence denotes Glycosylation and its related products, i.e., glycans, introduce changes to the viral envelope that make the virus fitted for interaction with the host cell membrane [5].
T52 1510-1607 Sentence denotes Generally, glycans are oligosaccharides linked to the dense decoration of the spike glycoprotein.
T53 1608-1768 Sentence denotes In particular, these oligosaccharides have shown to influence the folding of the S protein and proteolytic process so that they facilitate the virus cell entry.
T54 1769-1885 Sentence denotes Moreover, a virus with the glycosylated glycoprotein gains an extra feature for an escape from the immune responses.
T55 1886-1942 Sentence denotes Therefore, glycans are a good target for vaccine design.
T56 1943-2003 Sentence denotes Two main types of glycans are N-linked and O-linked glycans.
T57 2004-2041 Sentence denotes Both are released from glycoproteins.
T58 2042-2147 Sentence denotes Whereas enzymes fulfill the construction of N-glycans, chemical methods perform the release of O-glycans.
T59 2148-2325 Sentence denotes N-glycans are linked to the amino acid asparagine (Asn) residues (Asn-any amino acids except for proline- Ser or Thr) utilizing an N-glycosidic bond, mostly N-acetylglucosamine.
T60 2326-2463 Sentence denotes O-glycans are attached to the amino acid serine (Ser) and threonine (Thr) residues by the addition of an N-acetyl galactosamine (GalNAc).
T61 2464-2633 Sentence denotes For example, N-glycans exist in Hendra virus, SARS-CoV, influenza virus, hepatitis virus, HIV-1, and West Nile virus [6], and O-glycans have occurred in the Ebola virus.
T62 2634-2749 Sentence denotes The 2019-nCoV S protein includes 13 and 9N-linked glycosylation sequons in the S1 and S2 subunit, respectively [3].
T63 2750-2875 Sentence denotes All of these have previously occurred in the SARS-CoV S glycoprotein, except for four-linked glycosylation sequons in the S1.
T64 2876-3099 Sentence denotes Also, due to the existence of an amino acid proline in the polybasic cleavage site, which makes the inserted sequence PRRA, there are three O-linked glycans introduced to the 2019-nCoV RBD residues S673, T678, and S686 [7].
T65 3101-3222 Sentence denotes 3.1.3 SARS-CoV2 receptor binding domain contains six amino acids providing favorable positions for binding to human ACE2
T66 3223-3448 Sentence denotes When compared to SARS-CoV SB, the motif binding the human ACE2 to the SARS-CoV 2 SB showed a relatively higher binding affinity for human ACE2 as indicated in smaller equilibrium dissociation constant (2.9 nM vs. 7.7 nM) [3].
T67 3449-3833 Sentence denotes Structural analysis has demonstrated that fourteen positions critically take part in the receptor-binding domain of the SARS-CoV SB that contain eight conserved (T402, Y436, Y440, N473, Y475, T486, G488, and Y491) positions and six semi-conserved (R426 to N448, Y442 to L464, L472 to F495, N479 to Q502, Y484 to Q507, and T487 to N510) substitutions with respect to the SARS-CoV 2 SB.
T68 3835-3949 Sentence denotes 3.1.4 SARS-CoV2 receptor binding domain contains cyclic regions that can make interaction with cell-surface GRP78
T69 3950-4139 Sentence denotes Pep42 is a cyclic oligopeptide that, with its hydrophobic character, can selectively interact with cell surface glucose‐regulated protein 78 (GRP78), a member of 70 kDa heat shock proteins.
T70 4140-4361 Sentence denotes GRP78, also known as BiP or HSPA5, under endoplasmic reticulum stress, can be translocated from the endoplasmic reticulum to the membrane and helps to maintain cellular integrity under physiologic and pathological stress.
T71 4362-4553 Sentence denotes It critically contributes to various functions ranging from protein folding, transportation, and degradation to cell-signaling, proliferation, survival, apoptosis, inflammation, and immunity.
T72 4554-4597 Sentence denotes The expression of GRP78 decreases with age.
T73 4598-4752 Sentence denotes On the 2019-nCoV spike protein, 13 disulfide bonds are corresponding to 13 different cyclic regions thought to be similar to the cyclic form of Pep42 [8].
T74 4753-4918 Sentence denotes Among these, four regions I-IV take place in the outer surface of a putative receptor-binding domain (RBD) on the viral spike., including C361, C379, C391, and C480.
T75 4919-5001 Sentence denotes These regions share sequence similarity with Pep42, ranging from 15.38% to 46.15%.
T76 5002-5111 Sentence denotes However, only one of them, i.e., region IV (GRAVY = 0.08), is a hydrophobic region, like Pep42 (GRAVY = 1.1).
T77 5112-5336 Sentence denotes Structural models evaluate the energy contribution for region IV as a part of region III to the GRP78 to be about (−9.8 out of −14.0 kcal/mol), and the docking platform proposes region IV as the best region binding to GRP78.
T78 5337-5536 Sentence denotes The region IV can be linked to the substrate-binding domain β (SBDB) of GRP78 using five H-bonds (through P479, N481, E484, and N487) and four hydrophobic interactions (through T478, E484, and F486).