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From Proteopedia
Structural Investigations of the Substrate Specificity of Human O-GlcNAcase
Structural highlights
FunctionOGA_HUMAN Isoform 1: Cleaves GlcNAc but not GalNAc from O-glycosylated proteins. Can use p-nitrophenyl-beta-GlcNAc and 4-methylumbelliferone-GlcNAc as substrates but not p-nitrophenyl-beta-GalNAc or p-nitrophenyl-alpha-GlcNAc (in vitro) (PubMed:11148210). Does not bind acetyl-CoA and does not have histone acetyltransferase activity (PubMed:24088714).[1] [2] [3] [4] [5] Isoform 3: Cleaves GlcNAc but not GalNAc from O-glycosylated proteins. Can use p-nitrophenyl-beta-GlcNAc as substrate but not p-nitrophenyl-beta-GalNAc or p-nitrophenyl-alpha-GlcNAc (in vitro), but has about six times lower specific activity than isoform 1.[6] Publication Abstract from PubMedThe O-linked beta-N-acetyl glucosamine (O-GlcNAc) modification dynamically regulates the functions of numerous proteins. A single human enzyme O-linked beta-N-acetyl glucosaminase (O-GlcNAcase or OGA) hydrolyzes this modification. To date, it remains largely unknown how OGA recognizes various substrates. Here we report the structures of OGA in complex with each of four distinct glycopeptide substrates that contain a single O-GlcNAc modification on a serine or threonine residue. Intriguingly, these glycopeptides bind in a bidirectional yet conserved conformation within the substrate-binding cleft of OGA. This study provides fundamental insights into a general principle that confers the substrate binding adaptability and specificity to OGA in O-GlcNAc regulation.O-linked beta-N-acetyl glucosamine (O-GlcNAc) is an important protein modification that is hydrolyzed by O-GlcNAcase (OGA). Here the authors give insights into OGA substrate recognition by presenting four human OGA structures complexed with glycopeptide substrates containing a single O-GlcNAc modification on either a serine or threonine. Structural insights into the substrate binding adaptability and specificity of human O-GlcNAcase.,Li B, Li H, Hu CW, Jiang J Nat Commun. 2017 Sep 22;8(1):666. doi: 10.1038/s41467-017-00865-1. PMID:28939839[7] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Homo sapiens | Large Structures | Hu C-W | Jiang J | Li B | Li H
