PubMed:28138013 JSONTXT

{"project":"GlyCosmos6-Glycan-Motif-Image","denotations":[{"id":"T1","span":{"begin":0,"end":10},"obj":"Glycan_Motif"},{"id":"T2","span":{"begin":30,"end":40},"obj":"Glycan_Motif"},{"id":"T3","span":{"begin":88,"end":98},"obj":"Glycan_Motif"},{"id":"T4","span":{"begin":178,"end":188},"obj":"Glycan_Motif"}],"attributes":[{"id":"A1","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G00017MO"},{"id":"A2","pred":"image","subj":"T2","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G00017MO"},{"id":"A3","pred":"image","subj":"T3","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G00017MO"},{"id":"A4","pred":"image","subj":"T4","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G00017MO"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"GlyCosmos6-Glycan-Motif-Structure","denotations":[{"id":"T1","span":{"begin":0,"end":10},"obj":"https://glytoucan.org/Structures/Glycans/G00017MO"},{"id":"T2","span":{"begin":30,"end":40},"obj":"https://glytoucan.org/Structures/Glycans/G00017MO"},{"id":"T3","span":{"begin":88,"end":98},"obj":"https://glytoucan.org/Structures/Glycans/G00017MO"},{"id":"T4","span":{"begin":178,"end":188},"obj":"https://glytoucan.org/Structures/Glycans/G00017MO"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"sentences","denotations":[{"id":"TextSentencer_T1","span":{"begin":0,"end":169},"obj":"Sentence"},{"id":"TextSentencer_T2","span":{"begin":170,"end":286},"obj":"Sentence"},{"id":"TextSentencer_T3","span":{"begin":287,"end":415},"obj":"Sentence"},{"id":"TextSentencer_T4","span":{"begin":416,"end":422},"obj":"Sentence"},{"id":"TextSentencer_T5","span":{"begin":423,"end":557},"obj":"Sentence"},{"id":"TextSentencer_T6","span":{"begin":558,"end":728},"obj":"Sentence"},{"id":"TextSentencer_T7","span":{"begin":729,"end":937},"obj":"Sentence"},{"id":"TextSentencer_T8","span":{"begin":938,"end":1068},"obj":"Sentence"},{"id":"TextSentencer_T9","span":{"begin":1069,"end":1167},"obj":"Sentence"},{"id":"TextSentencer_T10","span":{"begin":1168,"end":1307},"obj":"Sentence"},{"id":"TextSentencer_T11","span":{"begin":1308,"end":1436},"obj":"Sentence"},{"id":"TextSentencer_T12","span":{"begin":1437,"end":1603},"obj":"Sentence"},{"id":"TextSentencer_T13","span":{"begin":1604,"end":1674},"obj":"Sentence"},{"id":"TextSentencer_T14","span":{"begin":1675,"end":1887},"obj":"Sentence"},{"id":"T1","span":{"begin":0,"end":169},"obj":"Sentence"},{"id":"T2","span":{"begin":170,"end":286},"obj":"Sentence"},{"id":"T3","span":{"begin":287,"end":415},"obj":"Sentence"},{"id":"T4","span":{"begin":416,"end":422},"obj":"Sentence"},{"id":"T5","span":{"begin":423,"end":557},"obj":"Sentence"},{"id":"T6","span":{"begin":558,"end":728},"obj":"Sentence"},{"id":"T7","span":{"begin":729,"end":937},"obj":"Sentence"},{"id":"T8","span":{"begin":938,"end":1068},"obj":"Sentence"},{"id":"T9","span":{"begin":1069,"end":1167},"obj":"Sentence"},{"id":"T10","span":{"begin":1168,"end":1307},"obj":"Sentence"},{"id":"T11","span":{"begin":1308,"end":1436},"obj":"Sentence"},{"id":"T12","span":{"begin":1437,"end":1603},"obj":"Sentence"},{"id":"T13","span":{"begin":1604,"end":1674},"obj":"Sentence"},{"id":"T14","span":{"begin":1675,"end":1887},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"NGLY1-deficiency","denotations":[{"id":"PD-NGLY1-deficiency-B_T1","span":{"begin":47,"end":53},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T2","span":{"begin":62,"end":68},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T3","span":{"begin":215,"end":221},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T4","span":{"begin":372,"end":378},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T5","span":{"begin":386,"end":392},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T6","span":{"begin":843,"end":849},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T7","span":{"begin":926,"end":932},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T8","span":{"begin":973,"end":979},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T9","span":{"begin":1358,"end":1365},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T10","span":{"begin":1428,"end":1435},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T11","span":{"begin":1468,"end":1474},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T12","span":{"begin":1502,"end":1509},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T13","span":{"begin":1528,"end":1534},"obj":"chem:24139"},{"id":"PD-NGLY1-deficiency-B_T14","span":{"begin":1870,"end":1876},"obj":"chem:24139"}],"namespaces":[{"prefix":"hgnc","uri":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:"},{"prefix":"omim","uri":"https://www.omim.org/entry/"},{"prefix":"chem","uri":"https://pubchem.ncbi.nlm.nih.gov/compound/"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"mondo_disease","denotations":[{"id":"T1","span":{"begin":200,"end":203},"obj":"Disease"},{"id":"T2","span":{"begin":313,"end":316},"obj":"Disease"},{"id":"T3","span":{"begin":445,"end":448},"obj":"Disease"}],"attributes":[{"id":"A1","pred":"mondo_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/MONDO_0019395"},{"id":"A2","pred":"mondo_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/MONDO_0019395"},{"id":"A3","pred":"mondo_id","subj":"T3","obj":"http://purl.obolibrary.org/obo/MONDO_0019395"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"Glycan-GlyCosmos","denotations":[{"id":"T1","span":{"begin":121,"end":127},"obj":"Glycan"},{"id":"T2","span":{"begin":279,"end":285},"obj":"Glycan"},{"id":"T3","span":{"begin":342,"end":348},"obj":"Glycan"},{"id":"T4","span":{"begin":454,"end":460},"obj":"Glycan"},{"id":"T5","span":{"begin":1346,"end":1352},"obj":"Glycan"},{"id":"T6","span":{"begin":1481,"end":1487},"obj":"Glycan"},{"id":"T7","span":{"begin":1653,"end":1659},"obj":"Glycan"},{"id":"T8","span":{"begin":1692,"end":1698},"obj":"Glycan"},{"id":"T9","span":{"begin":1856,"end":1862},"obj":"Glycan"}],"attributes":[{"id":"A1","pred":"glycosmos_id","subj":"T1","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A10","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A2","pred":"glycosmos_id","subj":"T2","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A11","pred":"image","subj":"T2","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A3","pred":"glycosmos_id","subj":"T3","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A12","pred":"image","subj":"T3","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A4","pred":"glycosmos_id","subj":"T4","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A13","pred":"image","subj":"T4","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A5","pred":"glycosmos_id","subj":"T5","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A14","pred":"image","subj":"T5","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A6","pred":"glycosmos_id","subj":"T6","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A15","pred":"image","subj":"T6","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A7","pred":"glycosmos_id","subj":"T7","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A16","pred":"image","subj":"T7","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A8","pred":"glycosmos_id","subj":"T8","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A17","pred":"image","subj":"T8","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A9","pred":"glycosmos_id","subj":"T9","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A18","pred":"image","subj":"T9","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"GlyCosmos15-MONDO","denotations":[{"id":"T1","span":{"begin":200,"end":203},"obj":"Disease"},{"id":"T2","span":{"begin":313,"end":316},"obj":"Disease"},{"id":"T3","span":{"begin":445,"end":448},"obj":"Disease"}],"attributes":[{"id":"A1","pred":"mondo_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/MONDO_0019395"},{"id":"A2","pred":"mondo_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/MONDO_0019395"},{"id":"A3","pred":"mondo_id","subj":"T3","obj":"http://purl.obolibrary.org/obo/MONDO_0019395"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"GlyCosmos15-NCBITAXON","denotations":[{"id":"T1","span":{"begin":287,"end":312},"obj":"OrganismTaxon"},{"id":"T2","span":{"begin":613,"end":625},"obj":"OrganismTaxon"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"119602"},{"id":"A2","pred":"db_id","subj":"T2","obj":"1883"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"GlyCosmos15-CL","denotations":[{"id":"T1","span":{"begin":140,"end":145},"obj":"Cell"}],"attributes":[{"id":"A1","pred":"cl_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/CL:4028003"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"GlyCosmos15-UBERON","denotations":[{"id":"T1","span":{"begin":575,"end":584},"obj":"Body_part"}],"attributes":[{"id":"A1","pred":"uberon_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/GO_0016020"},{"id":"A2","pred":"uberon_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/UBERON_0000094"},{"id":"A3","pred":"uberon_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/UBERON_0000158"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"sentences","denotations":[{"id":"TextSentencer_T1","span":{"begin":0,"end":169},"obj":"Sentence"},{"id":"TextSentencer_T2","span":{"begin":170,"end":286},"obj":"Sentence"},{"id":"TextSentencer_T3","span":{"begin":287,"end":415},"obj":"Sentence"},{"id":"TextSentencer_T4","span":{"begin":416,"end":422},"obj":"Sentence"},{"id":"TextSentencer_T5","span":{"begin":423,"end":557},"obj":"Sentence"},{"id":"TextSentencer_T6","span":{"begin":558,"end":728},"obj":"Sentence"},{"id":"TextSentencer_T7","span":{"begin":729,"end":937},"obj":"Sentence"},{"id":"TextSentencer_T8","span":{"begin":938,"end":1068},"obj":"Sentence"},{"id":"TextSentencer_T9","span":{"begin":1069,"end":1167},"obj":"Sentence"},{"id":"TextSentencer_T10","span":{"begin":1168,"end":1307},"obj":"Sentence"},{"id":"TextSentencer_T11","span":{"begin":1308,"end":1436},"obj":"Sentence"},{"id":"TextSentencer_T12","span":{"begin":1437,"end":1603},"obj":"Sentence"},{"id":"TextSentencer_T13","span":{"begin":1604,"end":1674},"obj":"Sentence"},{"id":"TextSentencer_T14","span":{"begin":1675,"end":1887},"obj":"Sentence"},{"id":"T1","span":{"begin":0,"end":169},"obj":"Sentence"},{"id":"T2","span":{"begin":170,"end":286},"obj":"Sentence"},{"id":"T3","span":{"begin":287,"end":415},"obj":"Sentence"},{"id":"T4","span":{"begin":416,"end":422},"obj":"Sentence"},{"id":"T5","span":{"begin":423,"end":557},"obj":"Sentence"},{"id":"T6","span":{"begin":558,"end":728},"obj":"Sentence"},{"id":"T7","span":{"begin":729,"end":937},"obj":"Sentence"},{"id":"T8","span":{"begin":938,"end":1068},"obj":"Sentence"},{"id":"T9","span":{"begin":1069,"end":1167},"obj":"Sentence"},{"id":"T10","span":{"begin":1168,"end":1307},"obj":"Sentence"},{"id":"T11","span":{"begin":1308,"end":1436},"obj":"Sentence"},{"id":"T12","span":{"begin":1437,"end":1603},"obj":"Sentence"},{"id":"T13","span":{"begin":1604,"end":1674},"obj":"Sentence"},{"id":"T14","span":{"begin":1675,"end":1887},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"GlyCosmos15-Sentences","blocks":[{"id":"T1","span":{"begin":0,"end":169},"obj":"Sentence"},{"id":"T2","span":{"begin":170,"end":286},"obj":"Sentence"},{"id":"T3","span":{"begin":287,"end":415},"obj":"Sentence"},{"id":"T4","span":{"begin":416,"end":422},"obj":"Sentence"},{"id":"T5","span":{"begin":423,"end":557},"obj":"Sentence"},{"id":"T6","span":{"begin":558,"end":728},"obj":"Sentence"},{"id":"T7","span":{"begin":729,"end":937},"obj":"Sentence"},{"id":"T8","span":{"begin":938,"end":1068},"obj":"Sentence"},{"id":"T9","span":{"begin":1069,"end":1167},"obj":"Sentence"},{"id":"T10","span":{"begin":1168,"end":1307},"obj":"Sentence"},{"id":"T11","span":{"begin":1308,"end":1436},"obj":"Sentence"},{"id":"T12","span":{"begin":1437,"end":1603},"obj":"Sentence"},{"id":"T13","span":{"begin":1604,"end":1674},"obj":"Sentence"},{"id":"T14","span":{"begin":1675,"end":1887},"obj":"Sentence"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"GlyCosmos15-Glycan","denotations":[{"id":"T1","span":{"begin":121,"end":127},"obj":"Glycan"},{"id":"T2","span":{"begin":279,"end":285},"obj":"Glycan"},{"id":"T3","span":{"begin":342,"end":348},"obj":"Glycan"},{"id":"T4","span":{"begin":454,"end":460},"obj":"Glycan"},{"id":"T5","span":{"begin":1346,"end":1352},"obj":"Glycan"},{"id":"T6","span":{"begin":1481,"end":1487},"obj":"Glycan"},{"id":"T7","span":{"begin":1653,"end":1659},"obj":"Glycan"},{"id":"T8","span":{"begin":1692,"end":1698},"obj":"Glycan"},{"id":"T9","span":{"begin":1856,"end":1862},"obj":"Glycan"}],"attributes":[{"id":"A1","pred":"glycosmos_id","subj":"T1","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A2","pred":"glycosmos_id","subj":"T2","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A3","pred":"glycosmos_id","subj":"T3","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A4","pred":"glycosmos_id","subj":"T4","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A5","pred":"glycosmos_id","subj":"T5","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A6","pred":"glycosmos_id","subj":"T6","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A7","pred":"glycosmos_id","subj":"T7","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A8","pred":"glycosmos_id","subj":"T8","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A9","pred":"glycosmos_id","subj":"T9","obj":"https://glycosmos.org/glycans/show/G97099AY"},{"id":"A10","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A11","pred":"image","subj":"T2","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A12","pred":"image","subj":"T3","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A13","pred":"image","subj":"T4","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A14","pred":"image","subj":"T5","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A15","pred":"image","subj":"T6","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A16","pred":"image","subj":"T7","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A17","pred":"image","subj":"T8","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"},{"id":"A18","pred":"image","subj":"T9","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G97099AY"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"NCBITAXON","denotations":[{"id":"T1","span":{"begin":287,"end":312},"obj":"OrganismTaxon"},{"id":"T2","span":{"begin":613,"end":625},"obj":"OrganismTaxon"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"119602"},{"id":"A2","pred":"db_id","subj":"T2","obj":"1883"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"Anatomy-UBERON","denotations":[{"id":"T1","span":{"begin":575,"end":584},"obj":"Body_part"}],"attributes":[{"id":"A1","pred":"uberon_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/GO_0016020"},{"id":"A2","pred":"uberon_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/UBERON_0000094"},{"id":"A3","pred":"uberon_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/UBERON_0000158"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}

{"project":"CL-cell","denotations":[{"id":"T1","span":{"begin":140,"end":145},"obj":"Cell"}],"attributes":[{"id":"A1","pred":"cl_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/CL:4028003"}],"text":"Hyaluronan synthase assembles hyaluronan on a [GlcNAc(β1,4)]n-GlcNAc(α1→)UDP primer and hyaluronan retains this residual chitin oligomer as a cap at the nonreducing end.\nClass I hyaluronan synthases (HAS) assemble [GlcNAc(β1,4)GlcUA(β1,3)]n-UDP at the reducing end and also make chitin. Streptococcus equisimilis HAS (SeHAS) also synthesizes chitin-UDP oligosaccharides, (GlcNAc-β1,4)n-GlcNAc(α1→)UDP (Weigel et al. 2015). Here we determined if HAS uses chitin-UDPs as primers to initiate HA synthesis, leaving the non-HA primer at the nonreducing (NR) end. HA made by SeHAS membranes was purified, digested with streptomyces lyase, and hydrophobic oligomers were enriched by solid phase extraction and analyzed by MALDI-TOF MS. Jack bean hexosaminidase (JBH) and MS/MS were used to analyze 19 m/z species of possible GnHn ions with clustered GlcNAc (G) residues attached to disaccharide units (H): (GlcNAcβ1,4)2-5[GlcUA(β1,3)GlcNAc]2-6. JBH digestion sequentially removed GlcNAc from the NR-end of GnHn oligomers, producing successively smaller GnH2-3 series members. Since lyase releases dehydro-oligos (dHn; M-18), only the unique NR-end oligo lacks dehydro-GlcUA. Hn oligomers were undetectable in lyase digests, whereas JBH treatment created new H2-6m/z peaks (i.e. HA tetra- through dodeca-oligomers). MS/MS of larger GnHn species produced chitin (2-5 GlcNAcs), HA oligomers and multiple smaller series members with fewer GlcNAcs. All NR-ends (97%) started with GlcNAc, as a chitin trimer (three GlcNAcs), indicating that GlcNAc(β1,4)2GlcNAc(α1→)-UDP may be optimal for initiation of HA synthesis. Also, HA made by live S. pyogenes cells had G4Hn chitin-oligo NR-ends. We conclude that chitin-UDP functions in vitro and in live cells as a primer to initiate synthesis of all HA chains and these primers remain at the NR-ends of HA chains as residual chitin caps [(GlcNAc-β1,4)3-4]."}