1t68
From Proteopedia
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{{STRUCTURE_1t68| PDB=1t68 | SCENE= }} | {{STRUCTURE_1t68| PDB=1t68 | SCENE= }} | ||
| - | + | ===Crystal structure of nitrophorin 2 complex with NO=== | |
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| - | ==Overview== | ||
| - | Nitrophorin 2 (NP2) (also known as prolixin-S) is a salivary protein that transports nitric oxide, binds histamine, and acts as an anticoagulant during blood feeding by the insect Rhodnius prolixus. The 2.0-A crystal structure of NP2 reveals an eight-stranded antiparallel beta-barrel containing a ferric heme coordinated through His(57), similar to the structures of NP1 and NP4. All four Rhodnius nitrophorins transport NO and sequester histamine through heme binding, but only NP2 acts as an anticoagulant. Here, we demonstrate that recombinant NP2, but not recombinant NP1 or NP4, is a potent anticoagulant; recombinant NP3 also displays minor activity. Comparison of the nitrophorin structures suggests that a surface region near the C terminus and the loops between beta strands B-C and E-F is responsible for the anticoagulant activity. NP2 also displays larger NO association rates and smaller dissociation rates than NP1 and NP4, which may result from a more open and more hydrophobic distal pocket, allowing more rapid solvent reorganization on ligand binding. The NP2 protein core differs from NP1 and NP4 in that buried Glu(53), which allows for larger NO release rates when deprotonated, hydrogen bonds to invariant Tyr(81). Surprisingly, this tyrosine lies on the protein surface in NP1 and NP4. | ||
==About this Structure== | ==About this Structure== | ||
| - | 1T68 is a | + | 1T68 is a 1 chain structure of sequence from [http://en.wikipedia.org/wiki/Rhodnius_prolixus Rhodnius prolixus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1T68 OCA]. |
==Reference== | ==Reference== | ||
| - | + | <ref group="xtra">PMID:10884386</ref><ref group="xtra">PMID:11560480</ref><references group="xtra"/> | |
[[Category: Rhodnius prolixus]] | [[Category: Rhodnius prolixus]] | ||
| - | [[Category: Single protein]] | ||
[[Category: Montfort, W R.]] | [[Category: Montfort, W R.]] | ||
[[Category: Weichsel, A.]] | [[Category: Weichsel, A.]] | ||
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[[Category: Nitric oxide]] | [[Category: Nitric oxide]] | ||
[[Category: Ruffling]] | [[Category: Ruffling]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
| + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Feb 16 12:17:13 2009'' | ||
Revision as of 10:17, 16 February 2009
Crystal structure of nitrophorin 2 complex with NO
About this Structure
1T68 is a 1 chain structure of sequence from Rhodnius prolixus. Full crystallographic information is available from OCA.
Reference
- Andersen JF, Montfort WR. The crystal structure of nitrophorin 2. A trifunctional antihemostatic protein from the saliva of Rhodnius prolixus. J Biol Chem. 2000 Sep 29;275(39):30496-503. PMID:10884386 doi:http://dx.doi.org/10.1074/jbc.M002857200
- Roberts SA, Weichsel A, Qiu Y, Shelnutt JA, Walker FA, Montfort WR. Ligand-induced heme ruffling and bent no geometry in ultra-high-resolution structures of nitrophorin 4. Biochemistry. 2001 Sep 25;40(38):11327-37. PMID:11560480
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