1nhe

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
(New page: 200px<br /><applet load="1nhe" size="450" color="white" frame="true" align="right" spinBox="true" caption="1nhe, resolution 2.50&Aring;" /> '''Crystal structure of...)
Current revision (08:49, 10 April 2024) (edit) (undo)
 
(32 intermediate revisions not shown.)
Line 1: Line 1:
-
[[Image:1nhe.gif|left|200px]]<br /><applet load="1nhe" size="450" color="white" frame="true" align="right" spinBox="true"
 
-
caption="1nhe, resolution 2.50&Aring;" />
 
-
'''Crystal structure of Lactose synthase complex with UDP'''<br />
 
-
==Overview==
+
==Crystal structure of Lactose synthase complex with UDP==
-
The lactose synthase (LS) enzyme is a 1:1 complex of a catalytic, component, beta1,4-galactosyltransferse (beta4Gal-T1) and a regulatory, component, alpha-lactalbumin (LA), a mammary gland-specific protein. LA, promotes the binding of glucose (Glc) to beta4Gal-T1, thereby altering its, sugar acceptor specificity from N-acetylglucosamine (GlcNAc) to glucose, which enables LS to synthesize lactose, the major carbohydrate component, of milk. The crystal structures of LS bound with various substrates were, solved at 2 A resolution. These structures reveal that upon substrate, binding to beta4Gal-T1, a large conformational change occurs in the region, comprising residues 345 to 365. This repositions His347 in such a way that, it can participate in the coordination of a metal ion, and creates a sugar, and LA-binding site. At the sugar-acceptor binding site, a hydrophobic, N-acetyl group-binding pocket is found, formed by residues Arg359, Phe360, and Ile363. In the Glc-bound structure, this hydrophobic pocket is absent., For the binding of Glc to LS, a reorientation of the Arg359 side-chain, occurs, which blocks the hydrophobic pocket and maximizes the interactions, with the Glc molecule. Thus, the role of LA is to hold Glc by hydrogen, bonding with the O-1 hydroxyl group in the acceptor-binding site on, beta4Gal-T1, while the N-acetyl group-binding pocket in beta4Gal-T1, adjusts to maximize the interactions with the Glc molecule. This study, provides details of a structural basis for the partially ordered kinetic, mechanism proposed for lactose synthase.
+
<StructureSection load='1nhe' size='340' side='right'caption='[[1nhe]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
 +
== Structural highlights ==
 +
<table><tr><td colspan='2'>[[1nhe]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Bos_taurus Bos taurus] and [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1j94 1j94]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NHE OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1NHE FirstGlance]. <br>
 +
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.5&#8491;</td></tr>
 +
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene>, <scene name='pdbligand=PG4:TETRAETHYLENE+GLYCOL'>PG4</scene>, <scene name='pdbligand=UDP:URIDINE-5-DIPHOSPHATE'>UDP</scene></td></tr>
 +
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1nhe FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1nhe OCA], [https://pdbe.org/1nhe PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1nhe RCSB], [https://www.ebi.ac.uk/pdbsum/1nhe PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1nhe ProSAT]</span></td></tr>
 +
</table>
 +
== Function ==
 +
[https://www.uniprot.org/uniprot/LALBA_MOUSE LALBA_MOUSE] Regulatory subunit of lactose synthase, changes the substrate specificity of galactosyltransferase in the mammary gland making glucose a good acceptor substrate for this enzyme. This enables LS to synthesize lactose, the major carbohydrate component of milk. In other tissues, galactosyltransferase transfers galactose onto the N-acetylglucosamine of the oligosaccharide chains in glycoproteins.
 +
== Evolutionary Conservation ==
 +
[[Image:Consurf_key_small.gif|200px|right]]
 +
Check<jmol>
 +
<jmolCheckbox>
 +
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/nh/1nhe_consurf.spt"</scriptWhenChecked>
 +
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
 +
<text>to colour the structure by Evolutionary Conservation</text>
 +
</jmolCheckbox>
 +
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1nhe ConSurf].
 +
<div style="clear:both"></div>
-
==About this Structure==
+
==See Also==
-
1NHE is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] and [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] with CA, UDP and PG4 as [http://en.wikipedia.org/wiki/ligands ligands]. This structure superseeds the now removed PDB entry 1J94. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1NHE OCA].
+
*[[Alpha-lactalbumin 3D structures|Alpha-lactalbumin 3D structures]]
-
 
+
*[[Glycosyltransferase 3D structures|Glycosyltransferase 3D structures]]
-
==Reference==
+
__TOC__
-
Crystal structure of lactose synthase reveals a large conformational change in its catalytic component, the beta1,4-galactosyltransferase-I., Ramakrishnan B, Qasba PK, J Mol Biol. 2001 Jun 29;310(1):205-18. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=11419947 11419947]
+
</StructureSection>
[[Category: Bos taurus]]
[[Category: Bos taurus]]
 +
[[Category: Large Structures]]
[[Category: Mus musculus]]
[[Category: Mus musculus]]
-
[[Category: Protein complex]]
+
[[Category: Qasba PK]]
-
[[Category: Qasba, P.K.]]
+
[[Category: Ramakrishnan B]]
-
[[Category: Ramakrishnan, B.]]
+
-
[[Category: CA]]
+
-
[[Category: PG4]]
+
-
[[Category: UDP]]
+
-
[[Category: crystal structure]]
+
-
[[Category: lactose synthase]]
+
-
[[Category: mad methods]]
+
-
 
+
-
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 22:15:25 2007''
+

Current revision

Crystal structure of Lactose synthase complex with UDP

PDB ID 1nhe

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools