PDBsum entry 2alg

Lipid transport

PDB id: 2alg

Contents

Protein chains

92 a.a. *

Ligands

DAO ×2

HP6

SO4

P6G

Waters ×136

* Residue conservation analysis

PDB id:

2alg

Name:

Lipid transport

Title:

Crystal structure of peach pru p3, the prototypic member of the family of plant non-specific lipid transfer protein pan-allergens

Structure:

Non-specific lipid transfer protein. Chain: a, b. Engineered: yes

Source:

Prunus persica. Peach. Organism_taxid: 3760. Gene: ltp. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

Resolution:

2.30Å R-factor: 0.204 R-free: 0.262

Authors:

N.Pasquato,R.Berni,C.Folli,S.Folloni,M.Cianci,S.Pantano,J.Helliwell, G.Zanotti

Key ref:

N.Pasquato et al. (2006). Crystal Structure of Peach Pru p 3, the Prototypic Member of the Family of Plant Non-specific Lipid Transfer Protein Pan-allergens. J Mol Biol, 356, 684-694. PubMed id: 16388823 DOI: 10.1016/j.jmb.2005.11.063

Date:

05-Aug-05 Release date: 29-Nov-05

Protein chains

P81402  (NLTP1_PRUPE) -  Non-specific lipid-transfer protein 1 from Prunus persica

Seq: 91 a.a.

Struc: 92 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

DOI no: 10.1016/j.jmb.2005.11.063

J Mol Biol 356:684-694 (2006)

PubMed id: 16388823

Crystal Structure of Peach Pru p 3, the Prototypic Member of the Family of Plant Non-specific Lipid Transfer Protein Pan-allergens.

N.Pasquato, R.Berni, C.Folli, S.Folloni, M.Cianci, S.Pantano, J.R.Helliwell, G.Zanotti.

ABSTRACT

This study describes the three-dimensional crystal structure of a non-specific lipid transport protein (ns-LTP) from Rosaceae. Whilst ns-LTPs from species other than Rosaceae, such as nuts, cereals, grape, oranges and vegetables are also responsible for plant food allergies, this is less frequent compared with ns-LTPs from Rosaceae in the Mediterranean area. In this heterologously expressed peach Pru p3, a ligand is present inside the central cavity of the protein, presumably a fatty acid that was present or produced in the culture medium of the expression organism Escherichia coli. Moreover, the two molecules of ns-LTP present in the asymmetric unit bind this ligand in a different way, suggesting a significant degree of plasticity for the peach ns-LTP binding cavity, despite the presence of four disulphide bridges. Two molecules are present in the asymmetric unit: molecule A is a fully liganded protein, while molecule B apparently represents a partially liganded state. Also, molecular dynamics simulation, along with other evidence, suggests that these two molecular conformations represent different states in solution. Comparison of the 3D models of different ns-LTPs justifies the evidence of a high degree of conservation of the putative IgE binding epitopes among proteins of the Rosaceae family and the presence of significant amino acid replacements in correspondence of the same regions in ns-LTPs of botanical species unrelated to Rosaceae.

Selected figure(s)

Figure 1.
Figure 1. (a) Stereo view of the C^a chain trace of molecule A of peach ns-LTP. The two hypothetical ligands (or the two orientations of the ligand) inside the cavity are shown (ball-and-stick model). The disulphide bridges are denoted by broken lines. (b) Same as (a), for molecule B.

Figure 2.
Figure 2. (a) Superposition of the ligands of wheat ns-LTP A molecule (1BWO PDB code) on the ligand of peach ns-LTP A and B molecules. The image shows the following elements: transparent van der Waals surface of peach ns-LTP, molecule A; stick view of the peach protein A (red) and B (green) ligands and stick representation of the two wheat ns-LTP lyso-palmytoyl-phosphatidylcholine ligands (yellow). (b) Superposition of ribbon models of molecules A (blue) and B (green). Ligands of molecule A are shown as CPK spheres. The Tyr79 side-chain of molecule B partially occupies the position of one of molecule A ligands (see the text for details).

The above figures are reprinted by permission from Elsevier: J Mol Biol (2006, 356, 684-694) copyright 2006.

Figures were selected by the author.