PDBsum entry: 1z3q

Antifungal protein

PDB id: 1z3q

Contents

Protein chain

200 a.a. *

Ligands

EDO ×3

Waters ×247

* Residue conservation analysis

PDB id:

1z3q

Name:

Antifungal protein

Title:

Resolution of the structure of the allergenic and antifungal banana fruit thaumatin-like protein at 1.7a

Structure:

Thaumatin-like protein. Chain: a

Source:

Musa acuminata. Organism_taxid: 4641. Tissue: pulp

Resolution:

1.70Å R-factor: 0.144 R-free: 0.177

Authors:

P.Leone,L.Menu-Bouaouiche,W.J.Peumans,A.Barre,F.Payan, A.Roussel,E.J.M.Van Damme,P.Rouge

Key ref:

P.Leone et al. (2006). Resolution of the structure of the allergenic and antifungal banana fruit thaumatin-like protein at 1.7-A. Biochimie, 88, 45-52. PubMed id: 16085352 DOI: 10.1016/j.biochi.2005.07.001

Date:

14-Mar-05 Release date: 24-Jan-06

Protein chain

O22322  (O22322_MUSAC) -  Ripening-associated protein (Fragment)

Seq: 193 a.a.

Struc: 200 a.a.*

* PDB and UniProt seqs differ at 7 residue positions (black crosses)

DOI no: 10.1016/j.biochi.2005.07.001

Biochimie 88:45-52 (2006)

PubMed id: 16085352

Resolution of the structure of the allergenic and antifungal banana fruit thaumatin-like protein at 1.7-A.

P.Leone, L.Menu-Bouaouiche, W.J.Peumans, F.Payan, A.Barre, A.Roussel, E.J.Van Damme, P.Rougé.

ABSTRACT

The structure of a thaumatin-like protein from banana (Musa acuminata) fruit, an allergen with antifungal properties, was solved at 1.7-A-resolution, by X-ray crystallography. Though the banana protein exhibits a very similar overall fold as thaumatin it markedly differs from the sweet-tasting protein by the presence of a surface exposed electronegative cleft. Due to the presence of this electronegative cleft, the banana thaumatin-like protein (Ban-TLP) acquires a strong (local) electronegative character that eventually explains the observed antifungal activity. Our structural analysis also revealed the presence of conserved residues of exposed epitopic determinants that are presumably responsible for the allergenic properties of banana fruit towards susceptible individuals, and provided evidence that the Ban-TLP shares some structurally highly conserved IgE-binding epitopes with thaumatin-like proteins from fruits or pollen from other plants. In addition, some overlap was detected between the predicted IgE-binding epitopes of the Ban-TLP and IgE-binding epitopes previously identified in the mountain cedar Jun a 3 TLP aeroallergen. The presence of these common epitopes offers a molecular basis for the cross-reactivity between aeroallergens and fruit allergens.