Function

Nitrophorins (NP) are NO transport heme-containing proteins from the saliva of blood-feeding insects which act as vasodilators and anti-platelet agents[1]. The NO is bound to the ferric form of NP with Kds in the micromolar or nanomolar range. Thus upon injection of the saliva into the tissue of the victim, the NO ca dissociate to cause vasodilation and inhibition of platelet aggregation[2].

  • Nitrophorin 2 is an inhibitor of the intrinsic factor X-activating complex[3].

Structural highlights

The which is unusual for heme-containing proteins[4]. Alpha Helices,  Beta Strands ,

 Loops , Turns. The [5].

Heme-containing nitrophorin 7 complex with NO and glycerol (PDB code 4xme)

Drag the structure with the mouse to rotate

3D Structures of nitrophorin3D Structures of nitrophorin

Updated on 17-July-2024

ReferencesReferences

  1. Andersen JF, Weichsel A, Balfour CA, Champagne DE, Montfort WR. The crystal structure of nitrophorin 4 at 1.5 A resolution: transport of nitric oxide by a lipocalin-based heme protein. Structure. 1998 Oct 15;6(10):1315-27. PMID:9782054
  2. Walker FA. Nitric oxide interaction with insect nitrophorins and thoughts on the electron configuration of the {FeNO}6 complex. J Inorg Biochem. 2005 Jan;99(1):216-36. PMID:15598503 doi:http://dx.doi.org/10.1016/j.jinorgbio.2004.10.009
  3. Zhang Y, Ribeiro JM, Guimarães JA, Walsh PN. Nitrophorin-2: a novel mixed-type reversible specific inhibitor of the intrinsic factor-X activating complex. Biochemistry. 1998 Jul 28;37(30):10681-90. PMID:9692958 doi:10.1021/bi973050y
  4. Walker FA. Nitric oxide interaction with insect nitrophorins and thoughts on the electron configuration of the {FeNO}6 complex. J Inorg Biochem. 2005 Jan;99(1):216-36. PMID:15598503 doi:http://dx.doi.org/10.1016/j.jinorgbio.2004.10.009
  5. Knipp M, Ogata H, Soavi G, Cerullo G, Allegri A, Abbruzzetti S, Bruno S, Viappiani C, Bidon-Chanal A, Luque FJ. Structure and dynamics of the membrane attaching nitric oxide transporter nitrophorin 7. F1000Res. 2015 Feb 13;4:45. doi: 10.12688/f1000research.6060.1. eCollection 2015. PMID:26167269 doi:http://dx.doi.org/10.12688/f1000research.6060.1

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

Michal Harel, Joel L. Sussman, Alexander Berchansky