PDBsum entry: 1pxz

Allergen

PDB id: 1pxz

Contents

Protein chains

346 a.a. *

Waters ×701

* Residue conservation analysis

PDB id:

1pxz

Name:

Allergen

Title:

1.7 angstrom crystal structure of jun a 1, the major allergen from cedar pollen

Structure:

Major pollen allergen jun a 1. Chain: a, b

Source:

Juniperus ashei. Ozark white cedar. Organism_taxid: 13101. Other_details: pollen

Resolution:

1.70Å R-factor: 0.193 R-free: 0.241

Authors:

E.W.Czerwinski,M.A.White,T.Midoro-Horiuti,E.G.Brooks, R.M.Goldblum

Key ref:

E.W.Czerwinski et al. (2005). Crystal structure of Jun a 1, the major cedar pollen allergen from Juniperus ashei, reveals a parallel beta-helical core. J Biol Chem, 280, 3740-3746. PubMed id: 15539389 DOI: 10.1074/jbc.M409655200

Date:

07-Jul-03 Release date: 16-Nov-04

Protein chains

P81294  (MPAJ1_JUNAS) -  Major pollen allergen Jun a 1

Seq: 367 a.a.

Struc: 346 a.a.

DOI no: 10.1074/jbc.M409655200

J Biol Chem 280:3740-3746 (2005)

PubMed id: 15539389

Crystal structure of Jun a 1, the major cedar pollen allergen from Juniperus ashei, reveals a parallel beta-helical core.

E.W.Czerwinski, T.Midoro-Horiuti, M.A.White, E.G.Brooks, R.M.Goldblum.

ABSTRACT

Pollen from cedar and cypress trees is a major cause of seasonal hypersensitivity in humans in several regions of the Northern Hemisphere. We report the first crystal structure of a cedar allergen, Jun a 1, from the pollen of the mountain cedar Juniperus ashei (Cupressaceae). The core of the structure consists primarily of a parallel beta-helix, which is nearly identical to that found in the pectin/pectate lyases from several plant pathogenic microorganisms. Four IgE epitopes mapped to the surface of the protein are accessible to the solvent. The conserved vWiDH sequence is covered by the first 30 residues of the N terminus. The potential reactive arginine, analogous to the pectin/pectate lyase reaction site, is accessible to the solvent, but the substrate binding groove is blocked by a histidine-aspartate salt bridge, a glutamine, and an alpha-helix, all of which are unique to Jun a 1. These observations suggest that steric hindrance in Jun a 1 precludes enzyme activity. The overall results suggest that it is the structure of Jun a 1 that makes it a potent allergen.

Selected figure(s)

Figure 3.
FIG. 3. Stereo view of the 2F[o] - F[c] map of the -helical strand (PB3.7-PB2.8) showing the cis-Pro231 configuration and the internal hydrogen bond (black dashed line) between Tyr245 and Met230 positioned by the cis-Pro231. Also shown are residues of the aliphatic stack (Val217 and Val240), the asparagine stack (Asn243), and the aromatic stack (Phe^222 and Tyr245). Electron density is contoured at the 2 level. Single letter amino acid abbreviations are used with position numbers.

Figure 7.
FIG. 7. Stereo view showing the location of the epitopes. The view is the same as in Fig. 1A.

The above figures are reprinted by permission from the ASBMB: J Biol Chem (2005, 280, 3740-3746) copyright 2005.

Figures were selected by an automated process.