2VSY

Xanthomonas campestris putative OGT (XCC0866), apostructure

Summary for 2VSY

• Entry DOI: 10.2210/pdb2vsy/pdb
• Related: 2JLB
• Descriptor: XCC0866, 2-[N-CYCLOHEXYLAMINO]ETHANE SULFONIC ACID, DI(HYDROXYETHYL)ETHER, ... (6 entities in total)
• Functional Keywords: transferase, glycosyl transferase, gt-b, ogt, protein o-glcnacylation
• Biological source: XANTHOMONAS CAMPESTRIS PV. CAMPESTRIS
• Total number of polymer chains: 2
• Total formula weight: 124177.12

Authors

Schuettelkopf, A.W.,Clarke, A.J.,van Aalten, D.M.F. (deposition date: 2008-05-01, release date: 2008-11-18, Last modification date: 2024-05-08)

Primary citation

Clarke, A.J.,Hurtado-Guerrero, R.,Pathak, S.,Schuttelkopf, A.W.,Borodkin, V.,Shepherd, S.M.,Ibrahim, A.F.M.,Van Aalten, D.M.F.
Structural Insights Into Mechanism and Specificity of O-Glcnac Transferase.
Embo J., 27:2780-, 2008

PubMed Abstract: Post-translational modification of protein serines/threonines with N-acetylglucosamine (O-GlcNAc) is dynamic, inducible and abundant, regulating many cellular processes by interfering with protein phosphorylation. O-GlcNAcylation is regulated by O-GlcNAc transferase (OGT) and O-GlcNAcase, both encoded by single, essential, genes in metazoan genomes. It is not understood how OGT recognises its sugar nucleotide donor and performs O-GlcNAc transfer onto proteins/peptides, and how the enzyme recognises specific cellular protein substrates. Here, we show, by X-ray crystallography and mutagenesis, that OGT adopts the (metal-independent) GT-B fold and binds a UDP-GlcNAc analogue at the bottom of a highly conserved putative peptide-binding groove, covered by a mobile loop. Strikingly, the tetratricopeptide repeats (TPRs) tightly interact with the active site to form a continuous 120 A putative interaction surface, whereas the previously predicted phosphatidylinositide-binding site locates to the opposite end of the catalytic domain. On the basis of the structure, we identify truncation/point mutants of the TPRs that have differential effects on activity towards proteins/peptides, giving first insights into how OGT may recognise its substrates.

PubMed: 18818698
DOI: 10.1038/EMBOJ.2008.186

Experimental method

X-RAY DIFFRACTION (2.1 Å)