PDBsum entry 4xcp

Retinol-binding protein

PDB id: 4xcp

Contents

Protein chain

155 a.a.

Ligands

PLM ×2

Waters ×136

PDB id:

4xcp

Name:

Retinol-binding protein

Title:

Fatty acid and retinol binding protein na-far-1 from necator americanus

Structure:

Nematode fatty acid retinoid binding protein. Chain: a. Fragment: unp residues 21-175. Engineered: yes. Mutation: yes

Source:

Necator americanus. Human hookworm. Organism_taxid: 51031. Gene: necame_14208. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.14Å R-factor: 0.204 R-free: 0.222

Authors:

M.Gabrielsen,M.F.Rey-Burusco,M.Ibanez-Shimabukuro,K.Griffiths, M.W.Kennedy,B.Corsico,B.O.Smith

Key ref:

M.F.Rey-Burusco et al. (2015). Diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by Na-FAR-1 from Necator americanus. Biochem J, 471, 403-414. PubMed id: 26318523 DOI: 10.1042/BJ20150068

Date:

18-Dec-14 Release date: 16-Sep-15

Protein chain

W2SRJ3  (W2SRJ3_NECAM) -  Fatty-acid and retinol-binding protein 1 from Necator americanus

Seq: 175 a.a.

Struc: 155 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

DOI no: 10.1042/BJ20150068

Biochem J 471:403-414 (2015)

PubMed id: 26318523

Diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by Na-FAR-1 from Necator americanus.

M.F.Rey-Burusco, M.Ibáñez-Shimabukuro, M.Gabrielsen, G.R.Franchini, A.J.Roe, K.Griffiths, B.Zhan, A.Cooper, M.W.Kennedy, B.Córsico, B.O.Smith.

ABSTRACT

Fatty acid and retinol-binding proteins (FARs) comprise a family of unusual α-helix rich lipid-binding proteins found exclusively in nematodes. They are secreted into host tissues by parasites of plants, animals and humans. The structure of a FAR protein from the free-living nematode Caenorhabditis elegans is available, but this protein [C. elegans FAR-7 (Ce-FAR-7)] is from a subfamily of FARs that does not appear to be important at the host/parasite interface. We have therefore examined [Necator americanus FAR-1 (Na-FAR-1)] from the blood-feeding intestinal parasite of humans, N. americanus. The 3D structure of Na-FAR-1 in its ligand-free and ligand-bound forms, determined by NMR (nuclear magnetic resonance) spectroscopy and X-ray crystallography respectively, reveals an α-helical fold similar to Ce-FAR-7, but Na-FAR-1 possesses a larger and more complex internal ligand-binding cavity and an additional C-terminal α-helix. Titration of apo-Na-FAR-1 with oleic acid, analysed by NMR chemical shift perturbation, reveals that at least four distinct protein-ligand complexes can be formed. Na-FAR-1 and possibly other FARs may have a wider repertoire for hydrophobic ligand binding, as confirmed in the present study by our finding that a range of neutral and polar lipids co-purify with the bacterially expressed recombinant protein. Finally, we show by immunohistochemistry that Na-FAR-1 is present in adult worms with a tissue distribution indicative of possible roles in nutrient acquisition by the parasite and in reproduction in the male.