1np1

CRYSTAL STRUCTURE OF THE COMPLEX OF NITROPHORIN 1 FROM RHODNIUS PROLIXUS WITH HISTAMINE

spinqualitylabelsall models 1np1, resolution 2.00Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1np1 is a 2 chain structure with sequence from Rhodnius prolixus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2Å Ligands: HEM, HSM, PO4 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function NP1_RHOPR Heme-based protein that deliver nitric oxide gas (NO) to the victim while feeding, resulting in vasodilation and inhibition of platelet aggregation. Also bind tightly to histamine, which is released by the host to induce wound healing. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed The nitrophorins are heme-based proteins from the salivary glands of the blood-sucking insect Rhodnius prolixus that deliver nitric oxide gas (NO) to the victim while feeding, resulting in vasodilation and inhibition of platelet aggregation. The nitrophorins also bind tightly to histamine, which is released by the host to induce wound healing. Here we present three crystal structures of nitrophorin 1 (NP1): bound to cyanide, which binds in a manner similar to NO (2.3 A resolution); bound to histamine (2.0 A resolution); and bound to what appears to be NH3 from the crystallization solution (2.0 A resolution). The NP1 structures reveal heme to be sandwiched between strands of a lipocalin-like beta-barrel, and in an arrangement unlike any other gas-transport protein discovered to date. The heme is six-coordinate with a histidine (His 59) on the proximal side, and ligand in a spacious pocket on the distal side. The structures confirm that NO and histamine compete for the same binding pocket and become buried on binding. The dissociation constant for histamine binding was found to be 19 nM, approximately 100-fold lower than that for NO. Crystal structures of a nitric oxide transport protein from a blood-sucking insect.,Weichsel A, Andersen JF, Champagne DE, Walker FA, Montfort WR Nat Struct Biol. 1998 Apr;5(4):304-9. PMID:9546222 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Nitrophorin

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