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1nou
From Proteopedia
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| - | [[Image:1nou.gif|left|200px]] | + | [[Image:1nou.gif|left|200px]] |
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| - | '''Native human lysosomal beta-hexosaminidase isoform B''' | + | {{Structure |
| + | |PDB= 1nou |SIZE=350|CAPTION= <scene name='initialview01'>1nou</scene>, resolution 2.40Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene> and <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Beta-N-acetylhexosaminidase Beta-N-acetylhexosaminidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.52 3.2.1.52] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''Native human lysosomal beta-hexosaminidase isoform B''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1NOU is a [ | + | 1NOU is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NOU OCA]. |
==Reference== | ==Reference== | ||
| - | Crystal structure of human beta-hexosaminidase B: understanding the molecular basis of Sandhoff and Tay-Sachs disease., Mark BL, Mahuran DJ, Cherney MM, Zhao D, Knapp S, James MN, J Mol Biol. 2003 Apr 11;327(5):1093-109. PMID:[http:// | + | Crystal structure of human beta-hexosaminidase B: understanding the molecular basis of Sandhoff and Tay-Sachs disease., Mark BL, Mahuran DJ, Cherney MM, Zhao D, Knapp S, James MN, J Mol Biol. 2003 Apr 11;327(5):1093-109. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/12662933 12662933] |
[[Category: Beta-N-acetylhexosaminidase]] | [[Category: Beta-N-acetylhexosaminidase]] | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
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[[Category: homodimer]] | [[Category: homodimer]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 12:59:40 2008'' |
Revision as of 10:59, 20 March 2008
| |||||||
| , resolution 2.40Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | and | ||||||
| Activity: | Beta-N-acetylhexosaminidase, with EC number 3.2.1.52 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Native human lysosomal beta-hexosaminidase isoform B
Contents |
Overview
In humans, two major beta-hexosaminidase isoenzymes exist: Hex A and Hex B. Hex A is a heterodimer of subunits alpha and beta (60% identity), whereas Hex B is a homodimer of beta-subunits. Interest in human beta-hexosaminidase stems from its association with Tay-Sachs and Sandhoff disease; these are prototypical lysosomal storage disorders resulting from the abnormal accumulation of G(M2)-ganglioside (G(M2)). Hex A degrades G(M2) by removing a terminal N-acetyl-D-galactosamine (beta-GalNAc) residue, and this activity requires the G(M2)-activator, a protein which solubilizes the ganglioside for presentation to Hex A. We present here the crystal structure of human Hex B, alone (2.4A) and in complex with the mechanistic inhibitors GalNAc-isofagomine (2.2A) or NAG-thiazoline (2.5A). From these, and the known X-ray structure of the G(M2)-activator, we have modeled Hex A in complex with the activator and ganglioside. Together, our crystallographic and modeling data demonstrate how alpha and beta-subunits dimerize to form either Hex A or Hex B, how these isoenzymes hydrolyze diverse substrates, and how many documented point mutations cause Sandhoff disease (beta-subunit mutations) and Tay-Sachs disease (alpha-subunit mutations).
Disease
Known diseases associated with this structure: Sandhoff disease, infantile, juvenile, and adult forms OMIM:[606873], Spinal muscular atrophy, juvenile OMIM:[606873]
About this Structure
1NOU is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Crystal structure of human beta-hexosaminidase B: understanding the molecular basis of Sandhoff and Tay-Sachs disease., Mark BL, Mahuran DJ, Cherney MM, Zhao D, Knapp S, James MN, J Mol Biol. 2003 Apr 11;327(5):1093-109. PMID:12662933
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