2aik: Difference between revisions
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'''Formylglycine generating enzyme C336S mutant covalently bound to substrate peptide LCTPSRA''' | '''Formylglycine generating enzyme C336S mutant covalently bound to substrate peptide LCTPSRA''' | ||
==Overview== | |||
The formylglycine (FGly)-generating enzyme (FGE) uses molecular oxygen to oxidize a conserved cysteine residue in all eukaryotic sulfatases to the catalytically active FGly. Sulfatases degrade and remodel sulfate esters, and inactivity of FGE results in multiple sulfatase deficiency, a fatal disease. The previously determined FGE crystal structure revealed two crucial cysteine residues in the active site, one of which was thought to be implicated in substrate binding. The other cysteine residue partakes in a novel oxygenase mechanism that does not rely on any cofactors. Here, we present crystal structures of the individual FGE cysteine mutants and employ chemical probing of wild-type FGE, which defined the cysteines to differ strongly in their reactivity. This striking difference in reactivity is explained by the distinct roles of these cysteine residues in the catalytic mechanism. Hitherto, an enzyme-substrate complex as an essential cornerstone for the structural evaluation of the FGly formation mechanism has remained elusive. We also present two FGE-substrate complexes with pentamer and heptamer peptides that mimic sulfatases. The peptides isolate a small cavity that is a likely binding site for molecular oxygen and could host reactive oxygen intermediates during cysteine oxidation. Importantly, these FGE-peptide complexes directly unveil the molecular bases of FGE substrate binding and specificity. Because of the conserved nature of FGE sequences in other organisms, this binding mechanism is of general validity. Furthermore, several disease-causing mutations in both FGE and sulfatases are explained by this binding mechanism. | |||
==About this Structure== | ==About this Structure== | ||
2AIK is a [[Protein complex]] structure of sequences 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=2AIK OCA]. | 2AIK is a [[Protein complex]] structure of sequences 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=2AIK OCA]. | ||
==Reference== | |||
A general binding mechanism for all human sulfatases by the formylglycine-generating enzyme., Roeser D, Preusser-Kunze A, Schmidt B, Gasow K, Wittmann JG, Dierks T, von Figura K, Rudolph MG, Proc Natl Acad Sci U S A. 2006 Jan 3;103(1):81-6. Epub 2005 Dec 20. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/16368756 16368756] | |||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
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[[Category: Endoplasmic reticulum]] | [[Category: Endoplasmic reticulum]] | ||
[[Category: Formylglycine]] | [[Category: Formylglycine]] | ||
[[Category: Hydrolase activator]] | |||
[[Category: Post-translational modification]] | [[Category: Post-translational modification]] | ||
[[Category: Protein binding]] | |||
[[Category: Sulfatase]] | [[Category: Sulfatase]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu May 22 22:19:39 2008'' | ||
Revision as of 22:19, 22 May 2008
Formylglycine generating enzyme C336S mutant covalently bound to substrate peptide LCTPSRA
OverviewOverview
The formylglycine (FGly)-generating enzyme (FGE) uses molecular oxygen to oxidize a conserved cysteine residue in all eukaryotic sulfatases to the catalytically active FGly. Sulfatases degrade and remodel sulfate esters, and inactivity of FGE results in multiple sulfatase deficiency, a fatal disease. The previously determined FGE crystal structure revealed two crucial cysteine residues in the active site, one of which was thought to be implicated in substrate binding. The other cysteine residue partakes in a novel oxygenase mechanism that does not rely on any cofactors. Here, we present crystal structures of the individual FGE cysteine mutants and employ chemical probing of wild-type FGE, which defined the cysteines to differ strongly in their reactivity. This striking difference in reactivity is explained by the distinct roles of these cysteine residues in the catalytic mechanism. Hitherto, an enzyme-substrate complex as an essential cornerstone for the structural evaluation of the FGly formation mechanism has remained elusive. We also present two FGE-substrate complexes with pentamer and heptamer peptides that mimic sulfatases. The peptides isolate a small cavity that is a likely binding site for molecular oxygen and could host reactive oxygen intermediates during cysteine oxidation. Importantly, these FGE-peptide complexes directly unveil the molecular bases of FGE substrate binding and specificity. Because of the conserved nature of FGE sequences in other organisms, this binding mechanism is of general validity. Furthermore, several disease-causing mutations in both FGE and sulfatases are explained by this binding mechanism.
About this StructureAbout this Structure
2AIK is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
ReferenceReference
A general binding mechanism for all human sulfatases by the formylglycine-generating enzyme., Roeser D, Preusser-Kunze A, Schmidt B, Gasow K, Wittmann JG, Dierks T, von Figura K, Rudolph MG, Proc Natl Acad Sci U S A. 2006 Jan 3;103(1):81-6. Epub 2005 Dec 20. PMID:16368756 Page seeded by OCA on Thu May 22 22:19:39 2008