PMC:7352545 / 22115-24578 JSONTXT

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    LitCovid_Glycan-Motif-Structure

    {"project":"LitCovid_Glycan-Motif-Structure","denotations":[{"id":"T66","span":{"begin":87,"end":93},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T67","span":{"begin":95,"end":97},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T68","span":{"begin":135,"end":137},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T69","span":{"begin":167,"end":173},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T70","span":{"begin":376,"end":382},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T71","span":{"begin":447,"end":450},"obj":"https://glytoucan.org/Structures/Glycans/G56516VH"},{"id":"T72","span":{"begin":447,"end":450},"obj":"https://glytoucan.org/Structures/Glycans/G91237TK"},{"id":"T73","span":{"begin":514,"end":520},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T74","span":{"begin":762,"end":768},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T75","span":{"begin":900,"end":906},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T76","span":{"begin":961,"end":963},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T77","span":{"begin":1025,"end":1031},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T78","span":{"begin":1048,"end":1050},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T79","span":{"begin":1116,"end":1118},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T80","span":{"begin":1413,"end":1419},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T81","span":{"begin":1741,"end":1743},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"}],"text":"4.2.1. C4-O-Acetyl Modification\nFor example, in the horse, C4-O-acetyl modification of Neu5Ac (SA) occupies more than 50% of the total SA content. The C4-O-acetylated Neu5Ac, Neu4,5Ac2, inhibits the influenza A2 virus HA. De-acetylation reagents such as NaOH or NaIO4 treatment completely hemagglutinate Neu4,5Ac2 by elimination of the C4-O-acetyl group [33]. The C4-O-acetyl Neu5Ac species are found in various sources such as equine erythrocyte GM3, starfish A. rubens and fish [34,35,36,37,38]. C4-O-acetylated Neu5Ac facilitates the initial attachment of viruses to target cells. Like the influenza C virus, infectious salmon anemia virus (ISAV), a member of the Orthomyxoviridae family, contains HE and HEF proteins to mediate virus entry and exit. C4-O-Ac Neu5Ac is the major receptor determinant of ISAV in receptor binding and destruction [38], while the influenza C virus recognizes C9-O-Ac Neu5Ac. The acetylesterase RDE of ISAV cleaves C4-O-Ac via 4-SA-O-acetylesterase with a short turnover time, whereas C9-O-Ac Neu5Ac is cleaved by 9-SA-O-acetylesterase with a long turnover time [34].\nThe position of SA O-acetylation is linked to functions including substrate differentiation of enzymes such as NAs and esterase by C4 O-Ac. Previous development of O-Ac site-selective NA inhibitors were based on the conceptual consideration of different O-Ac positions. The O-Ac of SAs is site-specific, as C4 of Neu5Ac is considered to be a potential position for modification. Historically, inhibitors of influenza A and B viruses-sialidases were designed by Von-Itzstein in 1993 [39]. The Ac group-based C4 substitution interacts with amino acid Glu-119 present in the active site of sialidase. Guanidine-attached C4 of C2–C3 unsaturated SA (Neu5Ac2en) inhibits activity of sialidases isolated from influenza A virus (Singapore/1/57) and B virus (Victoria/102/85). The same scenario was applied for sialidase inhibition of the human parainfluenza virus type 3, which has HN and fusion proteins [40]. The C4 of Neu5Ac2en was substituted by alkyl groups such as the O-ethyl group. For example, Zanamivir has a substitution with a 4-guanidino group with an IC50 of 25 μM. Thus, sialidase inhibition is important for C4 modification of Neu5Ac2en. Later, oseltamivir with the tradename Tamiflu (Basel, Switzerland) and zanamivir with the tradename Relenza (London, UK) were established [41]. These drugs exhibit some adverse side effects that restrict clinical use."}

    LitCovid-PD-FMA-UBERON

    {"project":"LitCovid-PD-FMA-UBERON","denotations":[{"id":"T211","span":{"begin":209,"end":211},"obj":"Body_part"},{"id":"T212","span":{"begin":435,"end":446},"obj":"Body_part"},{"id":"T213","span":{"begin":577,"end":582},"obj":"Body_part"},{"id":"T214","span":{"begin":712,"end":720},"obj":"Body_part"},{"id":"T215","span":{"begin":1638,"end":1648},"obj":"Body_part"},{"id":"T216","span":{"begin":1988,"end":1996},"obj":"Body_part"}],"attributes":[{"id":"A211","pred":"fma_id","subj":"T211","obj":"http://purl.org/sig/ont/fma/fma66595"},{"id":"A212","pred":"fma_id","subj":"T212","obj":"http://purl.org/sig/ont/fma/fma62845"},{"id":"A213","pred":"fma_id","subj":"T213","obj":"http://purl.org/sig/ont/fma/fma68646"},{"id":"A214","pred":"fma_id","subj":"T214","obj":"http://purl.org/sig/ont/fma/fma67257"},{"id":"A215","pred":"fma_id","subj":"T215","obj":"http://purl.org/sig/ont/fma/fma82739"},{"id":"A216","pred":"fma_id","subj":"T216","obj":"http://purl.org/sig/ont/fma/fma67257"}],"text":"4.2.1. C4-O-Acetyl Modification\nFor example, in the horse, C4-O-acetyl modification of Neu5Ac (SA) occupies more than 50% of the total SA content. The C4-O-acetylated Neu5Ac, Neu4,5Ac2, inhibits the influenza A2 virus HA. De-acetylation reagents such as NaOH or NaIO4 treatment completely hemagglutinate Neu4,5Ac2 by elimination of the C4-O-acetyl group [33]. The C4-O-acetyl Neu5Ac species are found in various sources such as equine erythrocyte GM3, starfish A. rubens and fish [34,35,36,37,38]. C4-O-acetylated Neu5Ac facilitates the initial attachment of viruses to target cells. Like the influenza C virus, infectious salmon anemia virus (ISAV), a member of the Orthomyxoviridae family, contains HE and HEF proteins to mediate virus entry and exit. C4-O-Ac Neu5Ac is the major receptor determinant of ISAV in receptor binding and destruction [38], while the influenza C virus recognizes C9-O-Ac Neu5Ac. The acetylesterase RDE of ISAV cleaves C4-O-Ac via 4-SA-O-acetylesterase with a short turnover time, whereas C9-O-Ac Neu5Ac is cleaved by 9-SA-O-acetylesterase with a long turnover time [34].\nThe position of SA O-acetylation is linked to functions including substrate differentiation of enzymes such as NAs and esterase by C4 O-Ac. Previous development of O-Ac site-selective NA inhibitors were based on the conceptual consideration of different O-Ac positions. The O-Ac of SAs is site-specific, as C4 of Neu5Ac is considered to be a potential position for modification. Historically, inhibitors of influenza A and B viruses-sialidases were designed by Von-Itzstein in 1993 [39]. The Ac group-based C4 substitution interacts with amino acid Glu-119 present in the active site of sialidase. Guanidine-attached C4 of C2–C3 unsaturated SA (Neu5Ac2en) inhibits activity of sialidases isolated from influenza A virus (Singapore/1/57) and B virus (Victoria/102/85). The same scenario was applied for sialidase inhibition of the human parainfluenza virus type 3, which has HN and fusion proteins [40]. The C4 of Neu5Ac2en was substituted by alkyl groups such as the O-ethyl group. For example, Zanamivir has a substitution with a 4-guanidino group with an IC50 of 25 μM. Thus, sialidase inhibition is important for C4 modification of Neu5Ac2en. Later, oseltamivir with the tradename Tamiflu (Basel, Switzerland) and zanamivir with the tradename Relenza (London, UK) were established [41]. These drugs exhibit some adverse side effects that restrict clinical use."}

    LitCovid-PD-MONDO

    {"project":"LitCovid-PD-MONDO","denotations":[{"id":"T84","span":{"begin":199,"end":208},"obj":"Disease"},{"id":"T85","span":{"begin":593,"end":602},"obj":"Disease"},{"id":"T86","span":{"begin":612,"end":622},"obj":"Disease"},{"id":"T87","span":{"begin":630,"end":636},"obj":"Disease"},{"id":"T88","span":{"begin":863,"end":872},"obj":"Disease"},{"id":"T89","span":{"begin":1507,"end":1516},"obj":"Disease"},{"id":"T90","span":{"begin":1802,"end":1811},"obj":"Disease"},{"id":"T91","span":{"begin":1930,"end":1962},"obj":"Disease"}],"attributes":[{"id":"A84","pred":"mondo_id","subj":"T84","obj":"http://purl.obolibrary.org/obo/MONDO_0005812"},{"id":"A85","pred":"mondo_id","subj":"T85","obj":"http://purl.obolibrary.org/obo/MONDO_0005812"},{"id":"A86","pred":"mondo_id","subj":"T86","obj":"http://purl.obolibrary.org/obo/MONDO_0005550"},{"id":"A87","pred":"mondo_id","subj":"T87","obj":"http://purl.obolibrary.org/obo/MONDO_0002280"},{"id":"A88","pred":"mondo_id","subj":"T88","obj":"http://purl.obolibrary.org/obo/MONDO_0005812"},{"id":"A89","pred":"mondo_id","subj":"T89","obj":"http://purl.obolibrary.org/obo/MONDO_0005812"},{"id":"A90","pred":"mondo_id","subj":"T90","obj":"http://purl.obolibrary.org/obo/MONDO_0005812"},{"id":"A91","pred":"mondo_id","subj":"T91","obj":"http://purl.obolibrary.org/obo/MONDO_0042974"}],"text":"4.2.1. C4-O-Acetyl Modification\nFor example, in the horse, C4-O-acetyl modification of Neu5Ac (SA) occupies more than 50% of the total SA content. The C4-O-acetylated Neu5Ac, Neu4,5Ac2, inhibits the influenza A2 virus HA. De-acetylation reagents such as NaOH or NaIO4 treatment completely hemagglutinate Neu4,5Ac2 by elimination of the C4-O-acetyl group [33]. The C4-O-acetyl Neu5Ac species are found in various sources such as equine erythrocyte GM3, starfish A. rubens and fish [34,35,36,37,38]. C4-O-acetylated Neu5Ac facilitates the initial attachment of viruses to target cells. Like the influenza C virus, infectious salmon anemia virus (ISAV), a member of the Orthomyxoviridae family, contains HE and HEF proteins to mediate virus entry and exit. C4-O-Ac Neu5Ac is the major receptor determinant of ISAV in receptor binding and destruction [38], while the influenza C virus recognizes C9-O-Ac Neu5Ac. The acetylesterase RDE of ISAV cleaves C4-O-Ac via 4-SA-O-acetylesterase with a short turnover time, whereas C9-O-Ac Neu5Ac is cleaved by 9-SA-O-acetylesterase with a long turnover time [34].\nThe position of SA O-acetylation is linked to functions including substrate differentiation of enzymes such as NAs and esterase by C4 O-Ac. Previous development of O-Ac site-selective NA inhibitors were based on the conceptual consideration of different O-Ac positions. The O-Ac of SAs is site-specific, as C4 of Neu5Ac is considered to be a potential position for modification. Historically, inhibitors of influenza A and B viruses-sialidases were designed by Von-Itzstein in 1993 [39]. The Ac group-based C4 substitution interacts with amino acid Glu-119 present in the active site of sialidase. Guanidine-attached C4 of C2–C3 unsaturated SA (Neu5Ac2en) inhibits activity of sialidases isolated from influenza A virus (Singapore/1/57) and B virus (Victoria/102/85). The same scenario was applied for sialidase inhibition of the human parainfluenza virus type 3, which has HN and fusion proteins [40]. The C4 of Neu5Ac2en was substituted by alkyl groups such as the O-ethyl group. For example, Zanamivir has a substitution with a 4-guanidino group with an IC50 of 25 μM. Thus, sialidase inhibition is important for C4 modification of Neu5Ac2en. Later, oseltamivir with the tradename Tamiflu (Basel, Switzerland) and zanamivir with the tradename Relenza (London, UK) were established [41]. These drugs exhibit some adverse side effects that restrict clinical use."}

    LitCovid-PD-CLO

    {"project":"LitCovid-PD-CLO","denotations":[{"id":"T260","span":{"begin":7,"end":9},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T261","span":{"begin":52,"end":57},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_9796"},{"id":"T262","span":{"begin":59,"end":61},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T263","span":{"begin":151,"end":153},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T264","span":{"begin":209,"end":211},"obj":"http://purl.obolibrary.org/obo/CLO_0001562"},{"id":"T265","span":{"begin":212,"end":217},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T266","span":{"begin":336,"end":338},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T267","span":{"begin":364,"end":366},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T268","span":{"begin":428,"end":434},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_9796"},{"id":"T269","span":{"begin":435,"end":446},"obj":"http://purl.obolibrary.org/obo/CL_0000232"},{"id":"T270","span":{"begin":461,"end":462},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"},{"id":"T271","span":{"begin":475,"end":479},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_117565"},{"id":"T272","span":{"begin":498,"end":500},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T273","span":{"begin":559,"end":566},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T274","span":{"begin":577,"end":582},"obj":"http://purl.obolibrary.org/obo/GO_0005623"},{"id":"T275","span":{"begin":605,"end":610},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T276","span":{"begin":637,"end":642},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T277","span":{"begin":651,"end":652},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"},{"id":"T278","span":{"begin":732,"end":737},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T279","span":{"begin":754,"end":756},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T280","span":{"begin":875,"end":880},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T281","span":{"begin":947,"end":949},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T282","span":{"begin":986,"end":987},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"},{"id":"T283","span":{"begin":1073,"end":1074},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"},{"id":"T284","span":{"begin":1095,"end":1097},"obj":"http://purl.obolibrary.org/obo/CLO_0001302"},{"id":"T285","span":{"begin":1231,"end":1233},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T286","span":{"begin":1382,"end":1385},"obj":"http://purl.obolibrary.org/obo/CLO_0051568"},{"id":"T287","span":{"begin":1407,"end":1409},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T288","span":{"begin":1440,"end":1441},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"},{"id":"T289","span":{"begin":1517,"end":1518},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"},{"id":"T290","span":{"begin":1523,"end":1524},"obj":"http://purl.obolibrary.org/obo/CLO_0001021"},{"id":"T291","span":{"begin":1525,"end":1532},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T292","span":{"begin":1607,"end":1609},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T293","span":{"begin":1672,"end":1678},"obj":"http://purl.obolibrary.org/obo/CLO_0001658"},{"id":"T294","span":{"begin":1717,"end":1719},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T295","span":{"begin":1723,"end":1725},"obj":"http://purl.obolibrary.org/obo/CLO_0002105"},{"id":"T296","span":{"begin":1723,"end":1725},"obj":"http://purl.obolibrary.org/obo/CLO_0051742"},{"id":"T297","span":{"begin":1765,"end":1773},"obj":"http://purl.obolibrary.org/obo/CLO_0001658"},{"id":"T298","span":{"begin":1812,"end":1813},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"},{"id":"T299","span":{"begin":1814,"end":1819},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T300","span":{"begin":1841,"end":1842},"obj":"http://purl.obolibrary.org/obo/CLO_0001021"},{"id":"T301","span":{"begin":1843,"end":1848},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T302","span":{"begin":1859,"end":1862},"obj":"http://purl.obolibrary.org/obo/CLO_0054060"},{"id":"T303","span":{"begin":1930,"end":1935},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_9606"},{"id":"T304","span":{"begin":1950,"end":1955},"obj":"http://purl.obolibrary.org/obo/NCBITaxon_10239"},{"id":"T305","span":{"begin":1970,"end":1973},"obj":"http://purl.obolibrary.org/obo/CLO_0051582"},{"id":"T306","span":{"begin":1974,"end":1976},"obj":"http://purl.obolibrary.org/obo/CLO_0003788"},{"id":"T307","span":{"begin":2007,"end":2009},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T308","span":{"begin":2105,"end":2108},"obj":"http://purl.obolibrary.org/obo/CLO_0051582"},{"id":"T309","span":{"begin":2109,"end":2110},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"},{"id":"T310","span":{"begin":2129,"end":2130},"obj":"http://purl.obolibrary.org/obo/CLO_0001020"},{"id":"T311","span":{"begin":2216,"end":2218},"obj":"http://purl.obolibrary.org/obo/CLO_0037284"},{"id":"T312","span":{"begin":2385,"end":2387},"obj":"http://purl.obolibrary.org/obo/CLO_0053794"}],"text":"4.2.1. C4-O-Acetyl Modification\nFor example, in the horse, C4-O-acetyl modification of Neu5Ac (SA) occupies more than 50% of the total SA content. The C4-O-acetylated Neu5Ac, Neu4,5Ac2, inhibits the influenza A2 virus HA. De-acetylation reagents such as NaOH or NaIO4 treatment completely hemagglutinate Neu4,5Ac2 by elimination of the C4-O-acetyl group [33]. The C4-O-acetyl Neu5Ac species are found in various sources such as equine erythrocyte GM3, starfish A. rubens and fish [34,35,36,37,38]. C4-O-acetylated Neu5Ac facilitates the initial attachment of viruses to target cells. Like the influenza C virus, infectious salmon anemia virus (ISAV), a member of the Orthomyxoviridae family, contains HE and HEF proteins to mediate virus entry and exit. C4-O-Ac Neu5Ac is the major receptor determinant of ISAV in receptor binding and destruction [38], while the influenza C virus recognizes C9-O-Ac Neu5Ac. The acetylesterase RDE of ISAV cleaves C4-O-Ac via 4-SA-O-acetylesterase with a short turnover time, whereas C9-O-Ac Neu5Ac is cleaved by 9-SA-O-acetylesterase with a long turnover time [34].\nThe position of SA O-acetylation is linked to functions including substrate differentiation of enzymes such as NAs and esterase by C4 O-Ac. Previous development of O-Ac site-selective NA inhibitors were based on the conceptual consideration of different O-Ac positions. The O-Ac of SAs is site-specific, as C4 of Neu5Ac is considered to be a potential position for modification. Historically, inhibitors of influenza A and B viruses-sialidases were designed by Von-Itzstein in 1993 [39]. The Ac group-based C4 substitution interacts with amino acid Glu-119 present in the active site of sialidase. Guanidine-attached C4 of C2–C3 unsaturated SA (Neu5Ac2en) inhibits activity of sialidases isolated from influenza A virus (Singapore/1/57) and B virus (Victoria/102/85). The same scenario was applied for sialidase inhibition of the human parainfluenza virus type 3, which has HN and fusion proteins [40]. The C4 of Neu5Ac2en was substituted by alkyl groups such as the O-ethyl group. For example, Zanamivir has a substitution with a 4-guanidino group with an IC50 of 25 μM. Thus, sialidase inhibition is important for C4 modification of Neu5Ac2en. Later, oseltamivir with the tradename Tamiflu (Basel, Switzerland) and zanamivir with the tradename Relenza (London, UK) were established [41]. These drugs exhibit some adverse side effects that restrict clinical use."}

    LitCovid-PD-CHEBI

    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C4-O-Acetyl Modification\nFor example, in the horse, C4-O-acetyl modification of Neu5Ac (SA) occupies more than 50% of the total SA content. The C4-O-acetylated Neu5Ac, Neu4,5Ac2, inhibits the influenza A2 virus HA. De-acetylation reagents such as NaOH or NaIO4 treatment completely hemagglutinate Neu4,5Ac2 by elimination of the C4-O-acetyl group [33]. The C4-O-acetyl Neu5Ac species are found in various sources such as equine erythrocyte GM3, starfish A. rubens and fish [34,35,36,37,38]. C4-O-acetylated Neu5Ac facilitates the initial attachment of viruses to target cells. Like the influenza C virus, infectious salmon anemia virus (ISAV), a member of the Orthomyxoviridae family, contains HE and HEF proteins to mediate virus entry and exit. C4-O-Ac Neu5Ac is the major receptor determinant of ISAV in receptor binding and destruction [38], while the influenza C virus recognizes C9-O-Ac Neu5Ac. The acetylesterase RDE of ISAV cleaves C4-O-Ac via 4-SA-O-acetylesterase with a short turnover time, whereas C9-O-Ac Neu5Ac is cleaved by 9-SA-O-acetylesterase with a long turnover time [34].\nThe position of SA O-acetylation is linked to functions including substrate differentiation of enzymes such as NAs and esterase by C4 O-Ac. Previous development of O-Ac site-selective NA inhibitors were based on the conceptual consideration of different O-Ac positions. The O-Ac of SAs is site-specific, as C4 of Neu5Ac is considered to be a potential position for modification. Historically, inhibitors of influenza A and B viruses-sialidases were designed by Von-Itzstein in 1993 [39]. The Ac group-based C4 substitution interacts with amino acid Glu-119 present in the active site of sialidase. Guanidine-attached C4 of C2–C3 unsaturated SA (Neu5Ac2en) inhibits activity of sialidases isolated from influenza A virus (Singapore/1/57) and B virus (Victoria/102/85). The same scenario was applied for sialidase inhibition of the human parainfluenza virus type 3, which has HN and fusion proteins [40]. The C4 of Neu5Ac2en was substituted by alkyl groups such as the O-ethyl group. For example, Zanamivir has a substitution with a 4-guanidino group with an IC50 of 25 μM. Thus, sialidase inhibition is important for C4 modification of Neu5Ac2en. Later, oseltamivir with the tradename Tamiflu (Basel, Switzerland) and zanamivir with the tradename Relenza (London, UK) were established [41]. These drugs exhibit some adverse side effects that restrict clinical use."}

    LitCovid-sentences

    {"project":"LitCovid-sentences","denotations":[{"id":"T211","span":{"begin":0,"end":6},"obj":"Sentence"},{"id":"T212","span":{"begin":7,"end":31},"obj":"Sentence"},{"id":"T213","span":{"begin":32,"end":146},"obj":"Sentence"},{"id":"T214","span":{"begin":147,"end":221},"obj":"Sentence"},{"id":"T215","span":{"begin":222,"end":359},"obj":"Sentence"},{"id":"T216","span":{"begin":360,"end":497},"obj":"Sentence"},{"id":"T217","span":{"begin":498,"end":583},"obj":"Sentence"},{"id":"T218","span":{"begin":584,"end":753},"obj":"Sentence"},{"id":"T219","span":{"begin":754,"end":907},"obj":"Sentence"},{"id":"T220","span":{"begin":908,"end":1099},"obj":"Sentence"},{"id":"T221","span":{"begin":1100,"end":1239},"obj":"Sentence"},{"id":"T222","span":{"begin":1240,"end":1369},"obj":"Sentence"},{"id":"T223","span":{"begin":1370,"end":1478},"obj":"Sentence"},{"id":"T224","span":{"begin":1479,"end":1587},"obj":"Sentence"},{"id":"T225","span":{"begin":1588,"end":1697},"obj":"Sentence"},{"id":"T226","span":{"begin":1698,"end":1867},"obj":"Sentence"},{"id":"T227","span":{"begin":1868,"end":2002},"obj":"Sentence"},{"id":"T228","span":{"begin":2003,"end":2081},"obj":"Sentence"},{"id":"T229","span":{"begin":2082,"end":2171},"obj":"Sentence"},{"id":"T230","span":{"begin":2172,"end":2245},"obj":"Sentence"},{"id":"T231","span":{"begin":2246,"end":2389},"obj":"Sentence"},{"id":"T232","span":{"begin":2390,"end":2463},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"4.2.1. C4-O-Acetyl Modification\nFor example, in the horse, C4-O-acetyl modification of Neu5Ac (SA) occupies more than 50% of the total SA content. The C4-O-acetylated Neu5Ac, Neu4,5Ac2, inhibits the influenza A2 virus HA. De-acetylation reagents such as NaOH or NaIO4 treatment completely hemagglutinate Neu4,5Ac2 by elimination of the C4-O-acetyl group [33]. The C4-O-acetyl Neu5Ac species are found in various sources such as equine erythrocyte GM3, starfish A. rubens and fish [34,35,36,37,38]. C4-O-acetylated Neu5Ac facilitates the initial attachment of viruses to target cells. Like the influenza C virus, infectious salmon anemia virus (ISAV), a member of the Orthomyxoviridae family, contains HE and HEF proteins to mediate virus entry and exit. C4-O-Ac Neu5Ac is the major receptor determinant of ISAV in receptor binding and destruction [38], while the influenza C virus recognizes C9-O-Ac Neu5Ac. The acetylesterase RDE of ISAV cleaves C4-O-Ac via 4-SA-O-acetylesterase with a short turnover time, whereas C9-O-Ac Neu5Ac is cleaved by 9-SA-O-acetylesterase with a long turnover time [34].\nThe position of SA O-acetylation is linked to functions including substrate differentiation of enzymes such as NAs and esterase by C4 O-Ac. Previous development of O-Ac site-selective NA inhibitors were based on the conceptual consideration of different O-Ac positions. The O-Ac of SAs is site-specific, as C4 of Neu5Ac is considered to be a potential position for modification. Historically, inhibitors of influenza A and B viruses-sialidases were designed by Von-Itzstein in 1993 [39]. The Ac group-based C4 substitution interacts with amino acid Glu-119 present in the active site of sialidase. Guanidine-attached C4 of C2–C3 unsaturated SA (Neu5Ac2en) inhibits activity of sialidases isolated from influenza A virus (Singapore/1/57) and B virus (Victoria/102/85). The same scenario was applied for sialidase inhibition of the human parainfluenza virus type 3, which has HN and fusion proteins [40]. The C4 of Neu5Ac2en was substituted by alkyl groups such as the O-ethyl group. For example, Zanamivir has a substitution with a 4-guanidino group with an IC50 of 25 μM. Thus, sialidase inhibition is important for C4 modification of Neu5Ac2en. Later, oseltamivir with the tradename Tamiflu (Basel, Switzerland) and zanamivir with the tradename Relenza (London, UK) were established [41]. These drugs exhibit some adverse side effects that restrict clinical use."}

    2_test

    {"project":"2_test","denotations":[{"id":"32604730-21618128-51943973","span":{"begin":355,"end":357},"obj":"21618128"},{"id":"32604730-31683930-51943974","span":{"begin":481,"end":483},"obj":"31683930"},{"id":"32604730-9090814-51943975","span":{"begin":484,"end":486},"obj":"9090814"},{"id":"32604730-16181722-51943976","span":{"begin":487,"end":489},"obj":"16181722"},{"id":"32604730-24833039-51943977","span":{"begin":490,"end":492},"obj":"24833039"},{"id":"32604730-14990724-51943978","span":{"begin":493,"end":495},"obj":"14990724"},{"id":"32604730-14990724-51943979","span":{"begin":848,"end":850},"obj":"14990724"},{"id":"32604730-31683930-51943980","span":{"begin":1095,"end":1097},"obj":"31683930"},{"id":"32604730-8502295-51943981","span":{"begin":1583,"end":1585},"obj":"8502295"},{"id":"32604730-17236768-51943982","span":{"begin":1998,"end":2000},"obj":"17236768"},{"id":"32604730-19770846-51943983","span":{"begin":2385,"end":2387},"obj":"19770846"},{"id":"T78050","span":{"begin":355,"end":357},"obj":"21618128"},{"id":"T53753","span":{"begin":481,"end":483},"obj":"31683930"},{"id":"T38465","span":{"begin":484,"end":486},"obj":"9090814"},{"id":"T72587","span":{"begin":487,"end":489},"obj":"16181722"},{"id":"T75131","span":{"begin":490,"end":492},"obj":"24833039"},{"id":"T15211","span":{"begin":493,"end":495},"obj":"14990724"},{"id":"T68693","span":{"begin":848,"end":850},"obj":"14990724"},{"id":"T49725","span":{"begin":1095,"end":1097},"obj":"31683930"},{"id":"T21609","span":{"begin":1583,"end":1585},"obj":"8502295"},{"id":"T5112","span":{"begin":1998,"end":2000},"obj":"17236768"},{"id":"T69375","span":{"begin":2385,"end":2387},"obj":"19770846"}],"text":"4.2.1. C4-O-Acetyl Modification\nFor example, in the horse, C4-O-acetyl modification of Neu5Ac (SA) occupies more than 50% of the total SA content. The C4-O-acetylated Neu5Ac, Neu4,5Ac2, inhibits the influenza A2 virus HA. De-acetylation reagents such as NaOH or NaIO4 treatment completely hemagglutinate Neu4,5Ac2 by elimination of the C4-O-acetyl group [33]. The C4-O-acetyl Neu5Ac species are found in various sources such as equine erythrocyte GM3, starfish A. rubens and fish [34,35,36,37,38]. C4-O-acetylated Neu5Ac facilitates the initial attachment of viruses to target cells. Like the influenza C virus, infectious salmon anemia virus (ISAV), a member of the Orthomyxoviridae family, contains HE and HEF proteins to mediate virus entry and exit. C4-O-Ac Neu5Ac is the major receptor determinant of ISAV in receptor binding and destruction [38], while the influenza C virus recognizes C9-O-Ac Neu5Ac. The acetylesterase RDE of ISAV cleaves C4-O-Ac via 4-SA-O-acetylesterase with a short turnover time, whereas C9-O-Ac Neu5Ac is cleaved by 9-SA-O-acetylesterase with a long turnover time [34].\nThe position of SA O-acetylation is linked to functions including substrate differentiation of enzymes such as NAs and esterase by C4 O-Ac. Previous development of O-Ac site-selective NA inhibitors were based on the conceptual consideration of different O-Ac positions. The O-Ac of SAs is site-specific, as C4 of Neu5Ac is considered to be a potential position for modification. Historically, inhibitors of influenza A and B viruses-sialidases were designed by Von-Itzstein in 1993 [39]. The Ac group-based C4 substitution interacts with amino acid Glu-119 present in the active site of sialidase. Guanidine-attached C4 of C2–C3 unsaturated SA (Neu5Ac2en) inhibits activity of sialidases isolated from influenza A virus (Singapore/1/57) and B virus (Victoria/102/85). The same scenario was applied for sialidase inhibition of the human parainfluenza virus type 3, which has HN and fusion proteins [40]. The C4 of Neu5Ac2en was substituted by alkyl groups such as the O-ethyl group. For example, Zanamivir has a substitution with a 4-guanidino group with an IC50 of 25 μM. Thus, sialidase inhibition is important for C4 modification of Neu5Ac2en. Later, oseltamivir with the tradename Tamiflu (Basel, Switzerland) and zanamivir with the tradename Relenza (London, UK) were established [41]. These drugs exhibit some adverse side effects that restrict clinical use."}

    LitCovid-PD-HP

    {"project":"LitCovid-PD-HP","denotations":[{"id":"T7","span":{"begin":630,"end":636},"obj":"Phenotype"}],"attributes":[{"id":"A7","pred":"hp_id","subj":"T7","obj":"http://purl.obolibrary.org/obo/HP_0001903"}],"text":"4.2.1. C4-O-Acetyl Modification\nFor example, in the horse, C4-O-acetyl modification of Neu5Ac (SA) occupies more than 50% of the total SA content. The C4-O-acetylated Neu5Ac, Neu4,5Ac2, inhibits the influenza A2 virus HA. De-acetylation reagents such as NaOH or NaIO4 treatment completely hemagglutinate Neu4,5Ac2 by elimination of the C4-O-acetyl group [33]. The C4-O-acetyl Neu5Ac species are found in various sources such as equine erythrocyte GM3, starfish A. rubens and fish [34,35,36,37,38]. C4-O-acetylated Neu5Ac facilitates the initial attachment of viruses to target cells. Like the influenza C virus, infectious salmon anemia virus (ISAV), a member of the Orthomyxoviridae family, contains HE and HEF proteins to mediate virus entry and exit. C4-O-Ac Neu5Ac is the major receptor determinant of ISAV in receptor binding and destruction [38], while the influenza C virus recognizes C9-O-Ac Neu5Ac. The acetylesterase RDE of ISAV cleaves C4-O-Ac via 4-SA-O-acetylesterase with a short turnover time, whereas C9-O-Ac Neu5Ac is cleaved by 9-SA-O-acetylesterase with a long turnover time [34].\nThe position of SA O-acetylation is linked to functions including substrate differentiation of enzymes such as NAs and esterase by C4 O-Ac. Previous development of O-Ac site-selective NA inhibitors were based on the conceptual consideration of different O-Ac positions. The O-Ac of SAs is site-specific, as C4 of Neu5Ac is considered to be a potential position for modification. Historically, inhibitors of influenza A and B viruses-sialidases were designed by Von-Itzstein in 1993 [39]. The Ac group-based C4 substitution interacts with amino acid Glu-119 present in the active site of sialidase. Guanidine-attached C4 of C2–C3 unsaturated SA (Neu5Ac2en) inhibits activity of sialidases isolated from influenza A virus (Singapore/1/57) and B virus (Victoria/102/85). The same scenario was applied for sialidase inhibition of the human parainfluenza virus type 3, which has HN and fusion proteins [40]. The C4 of Neu5Ac2en was substituted by alkyl groups such as the O-ethyl group. For example, Zanamivir has a substitution with a 4-guanidino group with an IC50 of 25 μM. Thus, sialidase inhibition is important for C4 modification of Neu5Ac2en. Later, oseltamivir with the tradename Tamiflu (Basel, Switzerland) and zanamivir with the tradename Relenza (London, UK) were established [41]. These drugs exhibit some adverse side effects that restrict clinical use."}