Pheromone binding protein: Difference between revisions

'''Pheromone binding proteins''' [http://en.wikipedia.org/wiki/Pheromone_binding_protein (PBP)] are type of Odorant binding proteins [http://en.wikipedia.org/wiki/Odorant-binding_protein (OBP)] - soluble proteins mediating the early stages of volatiles detection in both insects and vertebrates<ref>DOI:10.3389/fphys.2014.00320</ref>. The volatiles (pheromones and other small hydrophobic molecules) are solubilized by the OBPs and activate the chemoreceptors.  

 

 

Chemical communication is crucial in social insects, where a complicated and delicate system of signals must be maintained in order to preserve the fragile equilibrium between the queen and the workers. In the hive of the honey bee [http://en.wikipedia.org/wiki/Apis_mellifera ''Apis mellifera''] this equilibrium exists partially due to the extraction of blend of substances called queen mandibular pheromone [http://en.wikipedia.org/wiki/Honey_bee_pheromones#Queen_mandibular_pheromone (QMP)], by the queen <ref>Winston, M.L., 1987. The Biology of the Honey Bee. Harvard University Press, Cambridge, MA.</ref>. The three major component of the QMP blend are: 9-keto-2(E)-decenoic acid (9-ODA) and 9-hydroxy-2(E)-decenoic acid (9-HDA R-(−) or S-(+)).   

Pheromone-binding protein [http://www.uniprot.org/uniprot/Q9U9J6/ ASP1] of the honeybee [http://en.wikipedia.org/wiki/Apis_mellifera ''Apis mellifera''] L. (Hymenoptera: Apidea) was first isolated and characterized by Danty ''et al''. (1998)<ref>DOI:10.1016/j.jmb.2008.04.048</ref> from the bee antennae.  

The protein is composed of 144 amino acids, which forms 6 alpha helices. Three <scene name='60/609542/Disulfide_bonds/1'>3 disulfide bonds</scene> formed by 6 Cystein residues tied four helices: disulfide 20–51 between H1 and H3, 47– 98 between H3 and H6, and 107–89 between H6 and H5. 

 

== Interaction with the ligand 9-ODA==

One of the main components of the QMP <scene name='60/609542/9-oda/3'>9-ODA</scene>, is binding to the protein binding site along with a <scene name='60/609542/Glycerol/2'>glycerol molecule</scene>.The carboxyl end of 9-ODA points towards the solvent, and has no bonds with residues of the protein. The residues in the binding site are <scene name='60/609542/Binding_site/3'>hydrophobic</scene>, and the connection between 9-ODA and ASP1 involve hydrogen bonds.

 

</StructureSection>

==3D structures of pheromone-binding protein==

**[[3bfa]], [[3bfb]], [[3bfh]], [[3cyz]] – bPBP residues 26-144 + pheromone<br />

**[[3cz0]], [[3cz1]] - bPBP residues 26-144 + N-butyl benzene sulfonamide<br />

**[[3fe6]], [[3fe8]], [[3fe9]] - bPBP residues 26-144 + methyldotetracontane<br />

**[[2p70]] – sPBP + odorant<br />

**[[2p71]] – sPBP + iodohexadecane<br />

**[[4inw]], [[4inx]] – PBP + hexadecadienal – ''Amyelois transitella''<br />

**[[7vwa]] – bwPBP1 + odorant <br />