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LitCovid_Glycan-Motif-Structure

LitCovid-PD-FMA-UBERON

{"project":"LitCovid-PD-FMA-UBERON","denotations":[{"id":"T206","span":{"begin":132,"end":155},"obj":"Body_part"},{"id":"T207","span":{"begin":676,"end":699},"obj":"Body_part"},{"id":"T208","span":{"begin":745,"end":768},"obj":"Body_part"},{"id":"T209","span":{"begin":1401,"end":1416},"obj":"Body_part"},{"id":"T210","span":{"begin":1417,"end":1428},"obj":"Body_part"}],"attributes":[{"id":"A206","pred":"fma_id","subj":"T206","obj":"http://purl.org/sig/ont/fma/fma82788"},{"id":"A207","pred":"fma_id","subj":"T207","obj":"http://purl.org/sig/ont/fma/fma82788"},{"id":"A208","pred":"fma_id","subj":"T208","obj":"http://purl.org/sig/ont/fma/fma82788"},{"id":"A209","pred":"fma_id","subj":"T209","obj":"http://purl.org/sig/ont/fma/fma63843"},{"id":"A210","pred":"fma_id","subj":"T210","obj":"http://purl.org/sig/ont/fma/fma76577"}],"text":"4.1. General O-Acetylation of SA\nSAs have various derivatives of more than 50 chemically different structures formed from the basic N-acetylneuraminic acid (Neu5Ac) on the main ring of pyranose and the glycerol side chain. SA are modified by acetyl-, lactyl-, methyl- and sulfo-groups individually or in multiple combinations [28]. Multiple enzymes are involved in the modifications [29]. Historically, the first discovered SA was crystallized by Gunner Blix via a hot mild acid extraction of bovine submaxillary mucin in 1936. It consisted of two acetyl groups. Among these, only one acetyl group was attached to nitrogen [30]. Blix isolated a 9-O-acetyl SA of the common SA N-acetylneuraminic acid (Neu5Ac), chemically described as 9-O-acetyl-N-acetylneuraminic acid (Neu5,9Ac2). Neu5,9Ac2, Neu5Ac and Neu5Gc are naturally occurring SA species in mammals. A common modification is O-acetylation. In fact, O-acetylation of SAs is common in organisms.\nThe O-acetyl modification occurs in single positions of C-4, C-7, C-8 and C-9 of SA as well as in combined C-positions to yield Neu4,5Ac2, Neu5,9Ac2 and Neu5,7,9Ac3 SAs. Neu5Ac9NAc is a chemical and biologic mimic of Neu5,9Ac2 in the SA-glycans. The C-7 and/or C-9 O-acetylations are catalyzed by the SA O-acetyltransferase enzyme, Cas1 domain containing 1 (CasD1) (Figure 6). CasD1 catalyzes the addition of acetyl groups to the SA C-7 at the late Golgi apparatus compartment [31]. Thereafter, an enzyme termed “migrase” transfers the additional acetyl-group from C-7 to C-9, although this enzyme has not been identified [29]. CasD1 uses acetyl-coenzyme A as a donor substrate and CMP-Neu5Ac as an acceptor substrate, but with weak activity on CMP-Neu5Gc.\nBiologically, the SA O-acetylation event confers merits to hosts such as protection from pathogenic invasion and maintenance of systemic self-homeostasis. The O-acetylation event of SAs protects the SA-containing glycans from neuraminidase (NA)/sialidase action, because O-acetyl-groups inhibit microbial NA activity. The chemical structure of the O-acetyl group is quite unstable and susceptible to esterase enzymes. Sialic acid cleavage of the di-acetylated Neu5,7,9Ac3 by bacterial NAs decreases two-fold, when compared to mono-O-acetylated Neu5Ac. The O-acetylated glycan modification invites interaction with viruses, antibodies and mammalian lectins [32]. Therefore, the SA O-acetylation modification confers specific functions to organisms."}

LitCovid-PD-CLO

LitCovid-PD-CHEBI

LitCovid-PD-GO-BP

{"project":"LitCovid-PD-GO-BP","denotations":[{"id":"T43","span":{"begin":1851,"end":1862},"obj":"http://purl.obolibrary.org/obo/GO_0042592"}],"text":"4.1. General O-Acetylation of SA\nSAs have various derivatives of more than 50 chemically different structures formed from the basic N-acetylneuraminic acid (Neu5Ac) on the main ring of pyranose and the glycerol side chain. SA are modified by acetyl-, lactyl-, methyl- and sulfo-groups individually or in multiple combinations [28]. Multiple enzymes are involved in the modifications [29]. Historically, the first discovered SA was crystallized by Gunner Blix via a hot mild acid extraction of bovine submaxillary mucin in 1936. It consisted of two acetyl groups. Among these, only one acetyl group was attached to nitrogen [30]. Blix isolated a 9-O-acetyl SA of the common SA N-acetylneuraminic acid (Neu5Ac), chemically described as 9-O-acetyl-N-acetylneuraminic acid (Neu5,9Ac2). Neu5,9Ac2, Neu5Ac and Neu5Gc are naturally occurring SA species in mammals. A common modification is O-acetylation. In fact, O-acetylation of SAs is common in organisms.\nThe O-acetyl modification occurs in single positions of C-4, C-7, C-8 and C-9 of SA as well as in combined C-positions to yield Neu4,5Ac2, Neu5,9Ac2 and Neu5,7,9Ac3 SAs. Neu5Ac9NAc is a chemical and biologic mimic of Neu5,9Ac2 in the SA-glycans. The C-7 and/or C-9 O-acetylations are catalyzed by the SA O-acetyltransferase enzyme, Cas1 domain containing 1 (CasD1) (Figure 6). CasD1 catalyzes the addition of acetyl groups to the SA C-7 at the late Golgi apparatus compartment [31]. Thereafter, an enzyme termed “migrase” transfers the additional acetyl-group from C-7 to C-9, although this enzyme has not been identified [29]. CasD1 uses acetyl-coenzyme A as a donor substrate and CMP-Neu5Ac as an acceptor substrate, but with weak activity on CMP-Neu5Gc.\nBiologically, the SA O-acetylation event confers merits to hosts such as protection from pathogenic invasion and maintenance of systemic self-homeostasis. The O-acetylation event of SAs protects the SA-containing glycans from neuraminidase (NA)/sialidase action, because O-acetyl-groups inhibit microbial NA activity. The chemical structure of the O-acetyl group is quite unstable and susceptible to esterase enzymes. Sialic acid cleavage of the di-acetylated Neu5,7,9Ac3 by bacterial NAs decreases two-fold, when compared to mono-O-acetylated Neu5Ac. The O-acetylated glycan modification invites interaction with viruses, antibodies and mammalian lectins [32]. Therefore, the SA O-acetylation modification confers specific functions to organisms."}

LitCovid-sentences

{"project":"LitCovid-sentences","denotations":[{"id":"T185","span":{"begin":0,"end":4},"obj":"Sentence"},{"id":"T186","span":{"begin":5,"end":32},"obj":"Sentence"},{"id":"T187","span":{"begin":33,"end":222},"obj":"Sentence"},{"id":"T188","span":{"begin":223,"end":331},"obj":"Sentence"},{"id":"T189","span":{"begin":332,"end":388},"obj":"Sentence"},{"id":"T190","span":{"begin":389,"end":527},"obj":"Sentence"},{"id":"T191","span":{"begin":528,"end":562},"obj":"Sentence"},{"id":"T192","span":{"begin":563,"end":628},"obj":"Sentence"},{"id":"T193","span":{"begin":629,"end":781},"obj":"Sentence"},{"id":"T194","span":{"begin":782,"end":857},"obj":"Sentence"},{"id":"T195","span":{"begin":858,"end":897},"obj":"Sentence"},{"id":"T196","span":{"begin":898,"end":951},"obj":"Sentence"},{"id":"T197","span":{"begin":952,"end":1121},"obj":"Sentence"},{"id":"T198","span":{"begin":1122,"end":1197},"obj":"Sentence"},{"id":"T199","span":{"begin":1198,"end":1328},"obj":"Sentence"},{"id":"T200","span":{"begin":1329,"end":1434},"obj":"Sentence"},{"id":"T201","span":{"begin":1435,"end":1579},"obj":"Sentence"},{"id":"T202","span":{"begin":1580,"end":1708},"obj":"Sentence"},{"id":"T203","span":{"begin":1709,"end":1863},"obj":"Sentence"},{"id":"T204","span":{"begin":1864,"end":2026},"obj":"Sentence"},{"id":"T205","span":{"begin":2027,"end":2126},"obj":"Sentence"},{"id":"T206","span":{"begin":2127,"end":2260},"obj":"Sentence"},{"id":"T207","span":{"begin":2261,"end":2370},"obj":"Sentence"},{"id":"T208","span":{"begin":2371,"end":2456},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"4.1. General O-Acetylation of SA\nSAs have various derivatives of more than 50 chemically different structures formed from the basic N-acetylneuraminic acid (Neu5Ac) on the main ring of pyranose and the glycerol side chain. SA are modified by acetyl-, lactyl-, methyl- and sulfo-groups individually or in multiple combinations [28]. Multiple enzymes are involved in the modifications [29]. Historically, the first discovered SA was crystallized by Gunner Blix via a hot mild acid extraction of bovine submaxillary mucin in 1936. It consisted of two acetyl groups. Among these, only one acetyl group was attached to nitrogen [30]. Blix isolated a 9-O-acetyl SA of the common SA N-acetylneuraminic acid (Neu5Ac), chemically described as 9-O-acetyl-N-acetylneuraminic acid (Neu5,9Ac2). Neu5,9Ac2, Neu5Ac and Neu5Gc are naturally occurring SA species in mammals. A common modification is O-acetylation. In fact, O-acetylation of SAs is common in organisms.\nThe O-acetyl modification occurs in single positions of C-4, C-7, C-8 and C-9 of SA as well as in combined C-positions to yield Neu4,5Ac2, Neu5,9Ac2 and Neu5,7,9Ac3 SAs. Neu5Ac9NAc is a chemical and biologic mimic of Neu5,9Ac2 in the SA-glycans. The C-7 and/or C-9 O-acetylations are catalyzed by the SA O-acetyltransferase enzyme, Cas1 domain containing 1 (CasD1) (Figure 6). CasD1 catalyzes the addition of acetyl groups to the SA C-7 at the late Golgi apparatus compartment [31]. Thereafter, an enzyme termed “migrase” transfers the additional acetyl-group from C-7 to C-9, although this enzyme has not been identified [29]. CasD1 uses acetyl-coenzyme A as a donor substrate and CMP-Neu5Ac as an acceptor substrate, but with weak activity on CMP-Neu5Gc.\nBiologically, the SA O-acetylation event confers merits to hosts such as protection from pathogenic invasion and maintenance of systemic self-homeostasis. The O-acetylation event of SAs protects the SA-containing glycans from neuraminidase (NA)/sialidase action, because O-acetyl-groups inhibit microbial NA activity. The chemical structure of the O-acetyl group is quite unstable and susceptible to esterase enzymes. Sialic acid cleavage of the di-acetylated Neu5,7,9Ac3 by bacterial NAs decreases two-fold, when compared to mono-O-acetylated Neu5Ac. The O-acetylated glycan modification invites interaction with viruses, antibodies and mammalian lectins [32]. Therefore, the SA O-acetylation modification confers specific functions to organisms."}

2_test

{"project":"2_test","denotations":[{"id":"32604730-25921326-51943970","span":{"begin":624,"end":626},"obj":"25921326"},{"id":"32604730-26169044-51943971","span":{"begin":1430,"end":1432},"obj":"26169044"},{"id":"32604730-27936566-51943972","span":{"begin":2366,"end":2368},"obj":"27936566"},{"id":"T55761","span":{"begin":624,"end":626},"obj":"25921326"},{"id":"T96738","span":{"begin":1430,"end":1432},"obj":"26169044"},{"id":"T37447","span":{"begin":2366,"end":2368},"obj":"27936566"}],"text":"4.1. General O-Acetylation of SA\nSAs have various derivatives of more than 50 chemically different structures formed from the basic N-acetylneuraminic acid (Neu5Ac) on the main ring of pyranose and the glycerol side chain. SA are modified by acetyl-, lactyl-, methyl- and sulfo-groups individually or in multiple combinations [28]. Multiple enzymes are involved in the modifications [29]. Historically, the first discovered SA was crystallized by Gunner Blix via a hot mild acid extraction of bovine submaxillary mucin in 1936. It consisted of two acetyl groups. Among these, only one acetyl group was attached to nitrogen [30]. Blix isolated a 9-O-acetyl SA of the common SA N-acetylneuraminic acid (Neu5Ac), chemically described as 9-O-acetyl-N-acetylneuraminic acid (Neu5,9Ac2). Neu5,9Ac2, Neu5Ac and Neu5Gc are naturally occurring SA species in mammals. A common modification is O-acetylation. In fact, O-acetylation of SAs is common in organisms.\nThe O-acetyl modification occurs in single positions of C-4, C-7, C-8 and C-9 of SA as well as in combined C-positions to yield Neu4,5Ac2, Neu5,9Ac2 and Neu5,7,9Ac3 SAs. Neu5Ac9NAc is a chemical and biologic mimic of Neu5,9Ac2 in the SA-glycans. The C-7 and/or C-9 O-acetylations are catalyzed by the SA O-acetyltransferase enzyme, Cas1 domain containing 1 (CasD1) (Figure 6). CasD1 catalyzes the addition of acetyl groups to the SA C-7 at the late Golgi apparatus compartment [31]. Thereafter, an enzyme termed “migrase” transfers the additional acetyl-group from C-7 to C-9, although this enzyme has not been identified [29]. CasD1 uses acetyl-coenzyme A as a donor substrate and CMP-Neu5Ac as an acceptor substrate, but with weak activity on CMP-Neu5Gc.\nBiologically, the SA O-acetylation event confers merits to hosts such as protection from pathogenic invasion and maintenance of systemic self-homeostasis. The O-acetylation event of SAs protects the SA-containing glycans from neuraminidase (NA)/sialidase action, because O-acetyl-groups inhibit microbial NA activity. The chemical structure of the O-acetyl group is quite unstable and susceptible to esterase enzymes. Sialic acid cleavage of the di-acetylated Neu5,7,9Ac3 by bacterial NAs decreases two-fold, when compared to mono-O-acetylated Neu5Ac. The O-acetylated glycan modification invites interaction with viruses, antibodies and mammalian lectins [32]. Therefore, the SA O-acetylation modification confers specific functions to organisms."}