1o0r

Crystal structure of the catalytic domain of bovine beta1,4-galactosyltransferase complex with UDP-galactoseCrystal structure of the catalytic domain of bovine beta1,4-galactosyltransferase complex with UDP-galactose

Structural highlights 1o0r is a 2 chain structure with sequence from Bovin. This structure supersedes the now removed PDB entry 1kyb. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: , , , , Activity: N-acetyllactosamine synthase, with EC number 2.4.1.90 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function [B4GT1_BOVIN] The Golgi complex form catalyzes the production of lactose in the lactating mammary gland and could also be responsible for the synthesis of complex-type N-linked oligosaccharides in many glycoproteins as well as the carbohydrate moieties of glycolipids. The cell surface form functions as a recognition molecule during a variety of cell to cell and cell to matrix interactions, as those occurring during development and egg fertilization, by binding to specific oligosaccharide ligands on opposing cells or in the extracellular matrix. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed The crystal structure of the catalytic domain of bovine beta1,4-galactosyltransferase (Gal-T1) co-crystallized with UDP-Gal and MnCl(2) has been solved at 2.8 A resolution. The structure not only identifies galactose, the donor sugar binding site in Gal-T1, but also reveals an oligosaccharide acceptor binding site. The galactose moiety of UDP-Gal is found deep inside the catalytic pocket, interacting with Asp252, Gly292, Gly315, Glu317 and Asp318 residues. Compared to the native crystal structure reported earlier, the present UDP-Gal bound structure exhibits a large conformational change in residues 345-365 and a change in the side-chain orientation of Trp314. Thus, the binding of UDP-Gal induces a conformational change in Gal-T1, which not only creates the acceptor binding pocket for N-acetylglucosamine (GlcNAc) but also establishes the binding site for an extended sugar acceptor. The presence of a binding site that accommodates an extended sugar offers an explanation for the observation that an oligosaccharide with GlcNAc at the non-reducing end serves as a better acceptor than the monosaccharide, GlcNAc. Modeling studies using oligosaccharide acceptors indicate that a pentasaccharide, such as N-glycans with GlcNAc at their non-reducing ends, fits the site best. A sequence comparison of the human Gal-T family members indicates that although the binding site for the GlcNAc residue is highly conserved, the site that binds the extended sugar exhibits large variations. This is an indication that different Gal-T family members prefer different types of glycan acceptors with GlcNAc at their non-reducing ends. Crystal structure of beta1,4-galactosyltransferase complex with UDP-Gal reveals an oligosaccharide acceptor binding site.,Ramakrishnan B, Balaji PV, Qasba PK J Mol Biol. 2002 Apr 26;318(2):491-502. PMID:12051854 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Glycosyltransferase 3D structures

spinqualitylabelsall models 1o0r, resolution 2.30Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image