1n2k: Difference between revisions
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==Overview== | ==Overview== | ||
The structures of human arylsulfatase A crystals soaked in solutions | The structures of human arylsulfatase A crystals soaked in solutions containing 4-methylumbelliferyl phosphate and O-phospho-DL-tyrosine have been determined at 2.7- and 3.2-A resolution, respectively. The formylglycine in position 69, a residue crucial for catalytic activity, was unambiguously identified in both structures as forming a covalent bond to the phosphate moiety. A hydroxyl group is present at the Cbeta of residue 69 and the formation of one out of two possible stereomeric forms is strongly favoured. The structures confirm the importance of the gem-diol intermediate in the arylsulfatase's catalytic mechanism. The presence of an apparently stable covalent bond is consistent with the weak phosphatase activity observed for human arylsulfatase A. The structures of the complexes suggest that phosphate ions and phosphate esters inhibit arylsulfatase in non-covalent and covalent modes, respectively. The metal ion present in the active site of arylsulfatase A isolated from human placenta is Ca(2+) and not Mg(2+) as was found in the structure of the recombinant enzyme. | ||
==Disease== | ==Disease== | ||
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[[Category: phosphate esters hydrolysis]] | [[Category: phosphate esters hydrolysis]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:01:34 2008'' | ||
Revision as of 15:01, 21 February 2008
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Crystal structure of a covalent intermediate of endogenous human arylsulfatase A
OverviewOverview
The structures of human arylsulfatase A crystals soaked in solutions containing 4-methylumbelliferyl phosphate and O-phospho-DL-tyrosine have been determined at 2.7- and 3.2-A resolution, respectively. The formylglycine in position 69, a residue crucial for catalytic activity, was unambiguously identified in both structures as forming a covalent bond to the phosphate moiety. A hydroxyl group is present at the Cbeta of residue 69 and the formation of one out of two possible stereomeric forms is strongly favoured. The structures confirm the importance of the gem-diol intermediate in the arylsulfatase's catalytic mechanism. The presence of an apparently stable covalent bond is consistent with the weak phosphatase activity observed for human arylsulfatase A. The structures of the complexes suggest that phosphate ions and phosphate esters inhibit arylsulfatase in non-covalent and covalent modes, respectively. The metal ion present in the active site of arylsulfatase A isolated from human placenta is Ca(2+) and not Mg(2+) as was found in the structure of the recombinant enzyme.
DiseaseDisease
Known disease associated with this structure: Metachromatic leukodystrophy OMIM:[607574]
About this StructureAbout this Structure
1N2K is a Single protein structure of sequence from Homo sapiens with and as ligands. Active as Cerebroside-sulfatase, with EC number 3.1.6.8 Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of a covalent intermediate of endogenous human arylsulfatase A., Chruszcz M, Laidler P, Monkiewicz M, Ortlund E, Lebioda L, Lewinski K, J Inorg Biochem. 2003 Aug 1;96(2-3):386-92. PMID:12888274
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