2h2n: Difference between revisions
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'''Crystal structure of human soluble calcium-activated nucleotidase (SCAN) with calcium ion''' | {{Structure | ||
|PDB= 2h2n |SIZE=350|CAPTION= <scene name='initialview01'>2h2n</scene>, resolution 2.300Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene> and <scene name='pdbligand=ACT:ACETATE ION'>ACT</scene> | |||
|ACTIVITY= [http://en.wikipedia.org/wiki/Nucleoside-diphosphatase Nucleoside-diphosphatase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.1.6 3.6.1.6] | |||
|GENE= CANT1, SHAPY ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]) | |||
}} | |||
'''Crystal structure of human soluble calcium-activated nucleotidase (SCAN) with calcium ion''' | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
2H2N is a [ | 2H2N 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=2H2N OCA]. | ||
==Reference== | ==Reference== | ||
Calcium-dependent dimerization of human soluble calcium activated nucleotidase: characterization of the dimer interface., Yang M, Horii K, Herr AB, Kirley TL, J Biol Chem. 2006 Sep 22;281(38):28307-17. Epub 2006 Jul 11. PMID:[http:// | Calcium-dependent dimerization of human soluble calcium activated nucleotidase: characterization of the dimer interface., Yang M, Horii K, Herr AB, Kirley TL, J Biol Chem. 2006 Sep 22;281(38):28307-17. Epub 2006 Jul 11. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/16835225 16835225] | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Nucleoside-diphosphatase]] | [[Category: Nucleoside-diphosphatase]] | ||
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[[Category: nucleotide-binding]] | [[Category: nucleotide-binding]] | ||
''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 17:11:51 2008'' | ||
Revision as of 15:11, 20 March 2008
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| 2h2n, resolution 2.300Å | |||||||||||||
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| Ligands: | CA and ACT | ||||||||||||
| Gene: | CANT1, SHAPY (Homo sapiens) | ||||||||||||
| Activity: | Nucleoside-diphosphatase, with EC number 3.6.1.6 | ||||||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||||||
Crystal structure of human soluble calcium-activated nucleotidase (SCAN) with calcium ion
Overview
Mammals express a protein homologous to soluble nucleotidases used by blood-sucking insects to inhibit host blood clotting. These vertebrate nucleotidases may play a role in protein glycosylation. The activity of this enzyme family is strictly dependent on calcium, which induces a conformational change in the secreted, soluble human nucleotidase. The crystal structure of this human enzyme was recently solved; however, the mechanism of calcium activation and the basis for the calcium-induced changes remain unclear. In this study, using analytical ultracentrifugation and chemical cross-linking, we show that calcium or strontium induce noncovalent dimerization of the soluble human enzyme. The location and nature of the dimer interface was elucidated using a combination of site-directed mutagenesis and chemical cross-linking, coupled with crystallographic analyses. Replacement of Ile(170), Ser(172), and Ser(226) with cysteine residues resulted in calcium-dependent, sulfhydryl-specific intermolecular cross-linking, which was not observed after cysteine introduction at other surface locations. Analysis of a super-active mutant, E130Y, revealed that this mutant dimerized more readily than the wild-type enzyme. The crystal structure of the E130Y mutant revealed that the mutated residue is found in the dimer interface. In addition, expression of the full-length nucleotidase revealed that this membrane-bound form can also dimerize and that these dimers are stabilized by spontaneous oxidative cross-linking of Cys(30), located between the single transmembrane helix and the start of the soluble sequence. Thus, calcium-mediated dimerization may also represent a mechanism for regulation of the activity of this nucleotidase in the physiological setting of the endoplasmic reticulum or Golgi.
About this Structure
2H2N is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Calcium-dependent dimerization of human soluble calcium activated nucleotidase: characterization of the dimer interface., Yang M, Horii K, Herr AB, Kirley TL, J Biol Chem. 2006 Sep 22;281(38):28307-17. Epub 2006 Jul 11. PMID:16835225
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