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2mas
From Proteopedia
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|PDB= 2mas |SIZE=350|CAPTION= <scene name='initialview01'>2mas</scene>, resolution 2.3Å | |PDB= 2mas |SIZE=350|CAPTION= <scene name='initialview01'>2mas</scene>, resolution 2.3Å | ||
|SITE= <scene name='pdbsite=S1:Description+Not+Provided'>S1</scene>, <scene name='pdbsite=S2:Description+Not+Provided'>S2</scene>, <scene name='pdbsite=S3:Description+Not+Provided'>S3</scene> and <scene name='pdbsite=S4:Description+Not+Provided'>S4</scene> | |SITE= <scene name='pdbsite=S1:Description+Not+Provided'>S1</scene>, <scene name='pdbsite=S2:Description+Not+Provided'>S2</scene>, <scene name='pdbsite=S3:Description+Not+Provided'>S3</scene> and <scene name='pdbsite=S4:Description+Not+Provided'>S4</scene> | ||
| - | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene> | + | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=PIR:2-(4-AMINO-PHENYL)-5-HYDROXYMETHYL-PYRROLIDINE-3,4-DIOL'>PIR</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Purine_nucleosidase Purine nucleosidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.1 3.2.2.1] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Purine_nucleosidase Purine nucleosidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.1 3.2.2.1] </span> |
|GENE= IU-NH FROM C. FASCICULATA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=5656 Crithidia fasciculata]) | |GENE= IU-NH FROM C. FASCICULATA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=5656 Crithidia fasciculata]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2mas FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2mas OCA], [http://www.ebi.ac.uk/pdbsum/2mas PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=2mas RCSB]</span> | ||
}} | }} | ||
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[[Category: Sacchettini, J C.]] | [[Category: Sacchettini, J C.]] | ||
[[Category: Schramm, V L.]] | [[Category: Schramm, V L.]] | ||
| - | [[Category: CA]] | ||
| - | [[Category: PIR]] | ||
[[Category: hydrolase]] | [[Category: hydrolase]] | ||
[[Category: inosine]] | [[Category: inosine]] | ||
| Line 35: | Line 36: | ||
[[Category: uridine]] | [[Category: uridine]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 04:03:47 2008'' |
Revision as of 01:03, 31 March 2008
| |||||||
| , resolution 2.3Å | |||||||
|---|---|---|---|---|---|---|---|
| Sites: | , , and | ||||||
| Ligands: | , | ||||||
| Gene: | IU-NH FROM C. FASCICULATA (Crithidia fasciculata) | ||||||
| Activity: | Purine nucleosidase, with EC number 3.2.2.1 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
PURINE NUCLEOSIDE HYDROLASE WITH A TRANSITION STATE INHIBITOR
Overview
Nucleoside N-ribohydrolases are targets for disruption of purine salvage in the protozoan parasites. The structure of a trypanosomal N-ribohydrolase in complex with a transition-state inhibitor is reported at 2.3 A resolution. The nonspecific nucleoside hydrolase from Crithidia fasciculata cocrystallized with p-aminophenyliminoribitol reveals tightly bound Ca2+ as a catalytic site ligand. The complex with the transition-state inhibitor is characterized by (1) large protein conformational changes to create a hydrophobic leaving group site (2) C3'-exo geometry for the inhibitor, typical of a ribooxocarbenium ion (3) stabilization of the ribooxocarbenium analogue between the neighboring group 5'-hydroxyl and bidentate hydrogen bonds to Asn168; and (4) octacoordinate Ca2+ orients a catalytic site water and is liganded to two hydroxyls of the inhibitor. The mechanism is ribooxocarbenium stabilization with weak leaving group activation and is a departure from glucohydrolases which use paired carboxylates to achieve the transition state.
About this Structure
2MAS is a Single protein structure of sequence from Crithidia fasciculata. Full crystallographic information is available from OCA.
Reference
Trypanosomal nucleoside hydrolase. A novel mechanism from the structure with a transition-state inhibitor., Degano M, Almo SC, Sacchettini JC, Schramm VL, Biochemistry. 1998 May 5;37(18):6277-85. PMID:9572842
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