Crystal structure of the human odorant binding protein, OBPIIa.
Schiefner, A., Freier, R., Eichinger, A., Skerra, A.(2015) Proteins 83: 1180-1184
- PubMed: 25810031 
- DOI: https://doi.org/10.1002/prot.24797
- Primary Citation of Related Structures:  
4RUN - PubMed Abstract: 
Human odorant-binding protein, OBPIIa , is expressed by nasal epithelia to facilitate transport of hydrophobic odorant molecules across the aqueous mucus. Here, we report its crystallographic analysis at 2.6 Å resolution. OBPIIa is a monomeric protein that exhibits the classical lipocalin fold with a conserved eight-stranded β-barrel harboring a remarkably large hydrophobic pocket. Basic residues within the four loops that shape the entrance to this ligand-binding site evoke a positive electrostatic potential. Human OBPIIa shows distinct features compared with other mammalian OBPs, including a potentially reactive Cys side chain within its pocket similar to human tear lipocalin.
Organizational Affiliation: 
Munich Center for Integrated Protein Science (CIPS-M) and Lehrstuhl für Biologische Chemie, Technische Universität München, 85350 Freising-Weihenstephan, Germany.