2fyb

From Proteopedia

(Difference between revisions)

Revision as of 07:22, 20 June 2018

Crystal structure of the catalytic domain of the human beta1,4-galactosyltransferase mutant M339H in complex with Mn and UDP-galactose in open conformation

Structural highlights

2fyb is a 1 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	,
Related:	2fy7, 2fya, 2fyc, 2fyd
Gene:	B4GALT1, GGTB2 (HUMAN)
Activity:	N-acetyllactosamine synthase, with EC number 2.4.1.90
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Disease

[B4GT1_HUMAN] Defects in B4GALT1 are the cause of congenital disorder of glycosylation type 2D (CDG2D) [MIM:607091]. CDGs are a family of severe inherited diseases caused by a defect in protein N-glycosylation. They are characterized by under-glycosylated serum proteins. These multisystem disorders present with a wide variety of clinical features, such as disorders of the nervous system development, psychomotor retardation, dysmorphic features, hypotonia, coagulation disorders, and immunodeficiency. The broad spectrum of features reflects the critical role of N-glycoproteins during embryonic development, differentiation, and maintenance of cell functions.

Function

[B4GT1_HUMAN] 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

During the catalytic cycle of beta1,4-galactosyltransferase-1 (Gal-T1), upon the binding of Mn(2+) followed by UDP-Gal, two flexible loops, a long and a short loop, change their conformation from open to closed. We have determined the crystal structures of a human M340H-Gal-T1 mutant in the open conformation (apo-enzyme), its Mn(2+) and Mn(2+)-UDP-Gal-bound complexes, and of a pentenary complex of bovine Gal-T1-Mn(2+)-UDP-GalNAc-Glc-alpha-lactalbumin. These studies show that during the conformational changes in Gal-T1, the coordination of Mn(2+) undergoes significant changes. It loses a coordination bond with a water molecule bound in the open conformation of Gal-T1 while forming a new coordination bond with another water molecule in the closed conformation, creating an active ground-state structure that facilitates enzyme catalysis. In the crystal structure of the pentenary complex, the N-acetylglucosamine (GlcNAc) moiety is found cleaved from UDP-GalNAc and is placed 2.7A away from the O4 oxygen atom of the acceptor Glc molecule, yet to form the product. The anomeric C1 atom of the cleaved GalNAc moiety has only two covalent bonds with its non-hydrogen atoms (O5 and C2 atoms), similar to either an oxocarbenium ion or N-acetylgalactal form, which are crystallographically indistinguishable at the present resolution. The structure also shows that the newly formed, metal-coordinating water molecule forms a hydrogen bond with the beta-phosphate group of the cleaved UDP moiety. This hydrogen bond formation results in the rotation of the beta-phosphate group of UDP away from the cleaved GalNAc moiety, thereby preventing the re-formation of the UDP-sugar during catalysis. Therefore, this water molecule plays an important role during catalysis in ensuring that the catalytic reaction proceeds in a forward direction.

Structural snapshots of beta-1,4-galactosyltransferase-I along the kinetic pathway.,Ramakrishnan B, Ramasamy V, Qasba PK J Mol Biol. 2006 Apr 14;357(5):1619-33. Epub 2006 Feb 9. PMID:16497331^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Ramakrishnan B, Ramasamy V, Qasba PK. Structural snapshots of beta-1,4-galactosyltransferase-I along the kinetic pathway. J Mol Biol. 2006 Apr 14;357(5):1619-33. Epub 2006 Feb 9. PMID:16497331 doi:10.1016/j.jmb.2006.01.088

1 Structural highlights
2 Disease
3 Function
4 Evolutionary Conservation
5 Publication Abstract from PubMed
6 See Also
7 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/2fyb"

@@ Line 1: / Line 1: @@
 ==Crystal structure of the catalytic domain of the human beta1,4-galactosyltransferase mutant M339H in complex with Mn and UDP-galactose in open conformation==
 <StructureSection load='2fyb' size='340' side='right' caption='[[2fyb]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
@@ Line 7: / Line 8: @@
 <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">B4GALT1, GGTB2 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN])</td></tr>
 <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/N-acetyllactosamine_synthase N-acetyllactosamine synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.90 2.4.1.90] </span></td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2fyb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2fyb OCA], [http://pdbe.org/2fyb PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2fyb RCSB], [http://www.ebi.ac.uk/pdbsum/2fyb PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2fyb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2fyb OCA], [http://pdbe.org/2fyb PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2fyb RCSB], [http://www.ebi.ac.uk/pdbsum/2fyb PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2fyb ProSAT]</span></td></tr>
 </table>
 == Disease ==
@@ Line 17: / Line 18: @@
 Check<jmol>
   <jmolCheckbox>
-    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/fy/2fyb_consurf.spt"</scriptWhenChecked>
+    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/fy/2fyb_consurf.spt"</scriptWhenChecked>
     <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
     <text>to colour the structure by Evolutionary Conservation</text>

2fyb

From Proteopedia

Revision as of 07:22, 20 June 2018

Crystal structure of the catalytic domain of the human beta1,4-galactosyltransferase mutant M339H in complex with Mn and UDP-galactose in open conformation

Structural highlights

Disease

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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