{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Tan L"],"funding":["NCRR NIH HHS"],"pagination":["24575-83"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC2915693"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["285(32)"],"pubmed_abstract":["Classical arabinogalactan proteins partially defined by type II O-Hyp-linked arabinogalactans (Hyp-AGs) are structural components of the plant extracellular matrix. Recently we described the structure of a small Hyp-AG putatively based on repetitive trigalactosyl subunits and suggested that AGs are less complex and varied than generally supposed. Here we describe three additional AGs with similar subunits. The Hyp-AGs were isolated from two different arabinogalactan protein fusion glycoproteins expressed in tobacco cells; that is, a 22-residue Hyp-AG and a 20-residue Hyp-AG, both isolated from interferon alpha2b-(Ser-Hyp)(20), and a 14-residue Hyp-AG isolated from (Ala-Hyp)(51)-green fluorescent protein. We used NMR spectroscopy to establish the molecular structure of these Hyp-AGs, which share common features: (i) a galactan main chain composed of two 1-->3 beta-linked trigalactosyl blocks linked by a beta-1-->6 bond; (ii) bifurcated side chains with Ara, Rha, GlcUA, and a Gal 6-linked to Gal-1 and Gal-2 of the main-chain trigalactosyl repeats; (iii) a common side chain structure composed of up to six residues, the largest consisting of an alpha-L-Araf-(1-->5)-alpha-L-Araf-(1-->3)-alpha-L-Araf-(1-->3- unit and an alpha-L-Rhap-(1-->4)-beta-D-GlcUAp-(1-->6)-unit, both linked to Gal. The conformational ensemble obtained by using nuclear Overhauser effect data in structure calculations revealed a galactan main chain with a reverse turn involving the beta-1-->6 link between the trigalactosyl blocks, yielding a moderately compact structure stabilized by H-bonds."],"journal":["The Journal of biological chemistry"],"pubmed_title":["Plant O-hydroxyproline arabinogalactans are composed of repeating trigalactosyl subunits with short bifurcated side chains."],"pmcid":["PMC2915693"],"funding_grant_id":["P41 RR005351","2-P41-RR05351-06"],"pubmed_authors":["Tan L","Yuan C","Kieliszewski MJ","Qiu F","Varnai P","Lamport DT","Xu J"],"additional_accession":[]},"is_claimable":false,"name":"Plant O-hydroxyproline arabinogalactans are composed of repeating trigalactosyl subunits with short bifurcated side chains.","description":"Classical arabinogalactan proteins partially defined by type II O-Hyp-linked arabinogalactans (Hyp-AGs) are structural components of the plant extracellular matrix. Recently we described the structure of a small Hyp-AG putatively based on repetitive trigalactosyl subunits and suggested that AGs are less complex and varied than generally supposed. Here we describe three additional AGs with similar subunits. The Hyp-AGs were isolated from two different arabinogalactan protein fusion glycoproteins expressed in tobacco cells; that is, a 22-residue Hyp-AG and a 20-residue Hyp-AG, both isolated from interferon alpha2b-(Ser-Hyp)(20), and a 14-residue Hyp-AG isolated from (Ala-Hyp)(51)-green fluorescent protein. We used NMR spectroscopy to establish the molecular structure of these Hyp-AGs, which share common features: (i) a galactan main chain composed of two 1-->3 beta-linked trigalactosyl blocks linked by a beta-1-->6 bond; (ii) bifurcated side chains with Ara, Rha, GlcUA, and a Gal 6-linked to Gal-1 and Gal-2 of the main-chain trigalactosyl repeats; (iii) a common side chain structure composed of up to six residues, the largest consisting of an alpha-L-Araf-(1-->5)-alpha-L-Araf-(1-->3)-alpha-L-Araf-(1-->3- unit and an alpha-L-Rhap-(1-->4)-beta-D-GlcUAp-(1-->6)-unit, both linked to Gal. The conformational ensemble obtained by using nuclear Overhauser effect data in structure calculations revealed a galactan main chain with a reverse turn involving the beta-1-->6 link between the trigalactosyl blocks, yielding a moderately compact structure stabilized by H-bonds.","dates":{"release":"2010-01-01T00:00:00Z","publication":"2010 Aug","modification":"2024-11-14T15:25:20.079Z","creation":"2019-03-27T00:32:58Z"},"accession":"S-EPMC2915693","cross_references":{"pubmed":["20489210"],"doi":["10.1074/jbc.M109.100149","10.1074/jbc.m109.100149"]}}