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1rzy
From Proteopedia
(New page: 200px<br /><applet load="1rzy" size="450" color="white" frame="true" align="right" spinBox="true" caption="1rzy, resolution 1.80Å" /> '''Crystal structure of...) |
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| - | [[Image:1rzy.jpg|left|200px]]<br /><applet load="1rzy" size=" | + | [[Image:1rzy.jpg|left|200px]]<br /><applet load="1rzy" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1rzy, resolution 1.80Å" /> | caption="1rzy, resolution 1.80Å" /> | ||
'''Crystal structure of rabbit Hint complexed with N-ethylsulfamoyladenosine'''<br /> | '''Crystal structure of rabbit Hint complexed with N-ethylsulfamoyladenosine'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Hint, histidine triad nucleotide-binding protein, is a universally | + | Hint, histidine triad nucleotide-binding protein, is a universally conserved enzyme that hydrolyzes AMP linked to lysine and, in yeast, functions as a positive regulator of the RNA polymerase II C-terminal domain kinase, Kin28. To explore the biochemical and structural bases for the adenosine phosphoramidate hydrolase activity of rabbit Hint, we synthesized novel substrates linking a p-nitroaniline group to adenylate (AMP-pNA) and inhibitors that consist of an adenosine group and 5'-sulfamoyl (AdoOSO(2)NH(2)) or N-ethylsulfamoyl (AdoOSO(2)NHCH(2)CH(3)) group. AMP-pNA is a suitable substrate for Hint that allowed characterization of the inhibitors; titration of each inhibitor into AMP-pNA assays revealed their K(i) values. The N-ethylsulfamoyl derivative has a 13-fold binding advantage over the sulfamoyl adenosine. The 1.8-A cocrystal structure of rabbit Hint with N-ethylsulfamoyl adenosine revealed a binding site for the ethyl group against Trp-123, a residue that reaches across the Hint dimer interface to interact with the alkyl portion of the inhibitor and, presumably, the alkyl portion of a lysyl substrate. Ser-107 is positioned to donate a hydrogen bond to the leaving group nitrogen. Consistent with a role in acid-base catalysis, the Hint S107A mutant protein displayed depressed catalytic activity. |
==About this Structure== | ==About this Structure== | ||
| - | 1RZY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus] with 5AS as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1RZY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus] with <scene name='pdbligand=5AS:'>5AS</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1RZY OCA]. |
==Reference== | ==Reference== | ||
| Line 15: | Line 15: | ||
[[Category: Adams, M.]] | [[Category: Adams, M.]] | ||
[[Category: Baraniak, J.]] | [[Category: Baraniak, J.]] | ||
| - | [[Category: Blackburn, G | + | [[Category: Blackburn, G M.]] |
[[Category: Brenner, C.]] | [[Category: Brenner, C.]] | ||
[[Category: Kaczmarek, R.]] | [[Category: Kaczmarek, R.]] | ||
| - | [[Category: Krakowiak, A | + | [[Category: Krakowiak, A K.]] |
[[Category: Mekhalfia, A.]] | [[Category: Mekhalfia, A.]] | ||
| - | [[Category: Pace, H | + | [[Category: Pace, H C.]] |
| - | [[Category: Stec, W | + | [[Category: Stec, W J.]] |
[[Category: 5AS]] | [[Category: 5AS]] | ||
[[Category: hit protein; protein-inhibitor complex]] | [[Category: hit protein; protein-inhibitor complex]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:56:26 2008'' |
Revision as of 12:56, 21 February 2008
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Crystal structure of rabbit Hint complexed with N-ethylsulfamoyladenosine
Overview
Hint, histidine triad nucleotide-binding protein, is a universally conserved enzyme that hydrolyzes AMP linked to lysine and, in yeast, functions as a positive regulator of the RNA polymerase II C-terminal domain kinase, Kin28. To explore the biochemical and structural bases for the adenosine phosphoramidate hydrolase activity of rabbit Hint, we synthesized novel substrates linking a p-nitroaniline group to adenylate (AMP-pNA) and inhibitors that consist of an adenosine group and 5'-sulfamoyl (AdoOSO(2)NH(2)) or N-ethylsulfamoyl (AdoOSO(2)NHCH(2)CH(3)) group. AMP-pNA is a suitable substrate for Hint that allowed characterization of the inhibitors; titration of each inhibitor into AMP-pNA assays revealed their K(i) values. The N-ethylsulfamoyl derivative has a 13-fold binding advantage over the sulfamoyl adenosine. The 1.8-A cocrystal structure of rabbit Hint with N-ethylsulfamoyl adenosine revealed a binding site for the ethyl group against Trp-123, a residue that reaches across the Hint dimer interface to interact with the alkyl portion of the inhibitor and, presumably, the alkyl portion of a lysyl substrate. Ser-107 is positioned to donate a hydrogen bond to the leaving group nitrogen. Consistent with a role in acid-base catalysis, the Hint S107A mutant protein displayed depressed catalytic activity.
About this Structure
1RZY is a Single protein structure of sequence from Oryctolagus cuniculus with as ligand. Full crystallographic information is available from OCA.
Reference
Biochemical, crystallographic, and mutagenic characterization of hint, the AMP-lysine hydrolase, with novel substrates and inhibitors., Krakowiak A, Pace HC, Blackburn GM, Adams M, Mekhalfia A, Kaczmarek R, Baraniak J, Stec WJ, Brenner C, J Biol Chem. 2004 Apr 30;279(18):18711-6. Epub 2004 Feb 24. PMID:14982931
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