2oqa
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:2oqa.jpg|left|200px]] | [[Image:2oqa.jpg|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_2oqa", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
| - | | | + | or leave the SCENE parameter empty for the default display. |
| - | | | + | --> |
| - | + | {{STRUCTURE_2oqa| PDB=2oqa | SCENE= }} | |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''X-ray Sequence and Crystal Structure of Luffaculin 1, a Novel Type 1 Ribosome-inactivating Protein''' | '''X-ray Sequence and Crystal Structure of Luffaculin 1, a Novel Type 1 Ribosome-inactivating Protein''' | ||
| Line 19: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
| - | + | Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2OQA OCA]. | |
==Reference== | ==Reference== | ||
X-ray sequence and crystal structure of luffaculin 1, a novel type 1 ribosome-inactivating protein., Hou X, Chen M, Chen L, Meehan EJ, Xie J, Huang M, BMC Struct Biol. 2007 Apr 30;7:29. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17470286 17470286] | X-ray sequence and crystal structure of luffaculin 1, a novel type 1 ribosome-inactivating protein., Hou X, Chen M, Chen L, Meehan EJ, Xie J, Huang M, BMC Struct Biol. 2007 Apr 30;7:29. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17470286 17470286] | ||
| - | [[Category: Luffa acutangula]] | ||
| - | [[Category: Protein complex]] | ||
[[Category: Hou, X.]] | [[Category: Hou, X.]] | ||
[[Category: Huang, M.]] | [[Category: Huang, M.]] | ||
| - | [[Category: | + | [[Category: Mixed alpha helix and beta sheet]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 11:26:31 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 08:26, 4 May 2008
X-ray Sequence and Crystal Structure of Luffaculin 1, a Novel Type 1 Ribosome-inactivating Protein
Overview
BACKGROUND: Protein sequence can be obtained through Edman degradation, mass spectrometry, or cDNA sequencing. High resolution X-ray crystallography can also be used to derive protein sequence information, but faces the difficulty in distinguishing the Asp/Asn, Glu/Gln, and Val/Thr pairs. Luffaculin 1 is a new type 1 ribosome-inactivating protein (RIP) isolated from the seeds of Luffa acutangula. Besides rRNA N-glycosidase activity, luffaculin 1 also demonstrates activities including inhibiting tumor cells' proliferation and inducing tumor cells' differentiation. RESULTS: The crystal structure of luffaculin 1 was determined at 1.4 A resolution. Its amino-acid sequence was derived from this high resolution structure using the following criteria: 1) high resolution electron density; 2) comparison of electron density between two molecules that exist in the same crystal; 3) evaluation of the chemical environment of residues to break down the sequence assignment ambiguity in residue pairs Glu/Gln, Asp/Asn, and Val/Thr; 4) comparison with sequences of the homologous proteins. Using the criteria 1 and 2, 66% of the residues can be assigned. By incorporating with criterion 3, 86% of the residues were assigned, suggesting the effectiveness of chemical environment evaluation in breaking down residue ambiguity. In total, 94% of the luffaculin 1 sequence was assigned with high confidence using this improved X-ray sequencing strategy. Two N-acetylglucosamine moieties, linked respectively to the residues Asn77 and Asn84, can be identified in the structure. Residues Tyr70, Tyr110, Glu159 and Arg162 define the active site of luffaculin 1 as an RNA N-glycosidase. CONCLUSION: X-ray sequencing method can be effective to derive sequence information of proteins. The evaluation of the chemical environment of residues is a useful method to break down the assignment ambiguity in Glu/Gln, Asp/Asn, and Val/Thr pairs. The sequence and the crystal structure confirm that luffaculin 1 is a new type 1 RIP.
About this Structure
Full crystallographic information is available from OCA.
Reference
X-ray sequence and crystal structure of luffaculin 1, a novel type 1 ribosome-inactivating protein., Hou X, Chen M, Chen L, Meehan EJ, Xie J, Huang M, BMC Struct Biol. 2007 Apr 30;7:29. PMID:17470286 Page seeded by OCA on Sun May 4 11:26:31 2008
