8WKH

Crystal structure of group 13 allergen from Blomia tropicalis

Summary for 8WKH

• Entry DOI: 10.2210/pdb8wkh/pdb
• Descriptor: Fatty acid-binding protein, 2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL, DI(HYDROXYETHYL)ETHER, ... (4 entities in total)
• Functional Keywords: beta barrel, helix, allergen
• Biological source: Blomia tropicalis (Mite)
• Total number of polymer chains: 1
• Total formula weight: 15107.12

Authors

Zhu, K.L.,Gong, Y.,Cui, Y.B. (deposition date: 2023-09-27, release date: 2023-11-22, Last modification date: 2023-11-29)

Primary citation

Zhou, Y.,Zhu, K.,Li, Q.,Zhou, D.,Ren, Y.,Liao, Y.,Cao, P.,Gong, Y.,Cui, Y.
Immunobiological properties and structure analysis of group 13 allergen from Blomia tropicalis and its IgE-mediated cross-reactivity.
Int.J.Biol.Macromol., 254:127788-127788, 2023

PubMed Abstract: Blomia tropicalis is an important species of allergenic mite. Structurally related cross-reactive allergens are involved in pathogenesis of clinical symptoms. The present study focused on recombinant allergen rBlo t 13 from B. tropicalis, including investigation of its structure, immunological properties, IgE-mediated cross-reactivity. In this work, the prokaryotic expression plasmids pET-28(a)-Blo t 13, pET-28(a)-Der f 13, and pET-28(a)-Tyr p 13 were constructed, transformed into E. coli Rosetta (DE3) pLysS, and purified by nickel affinity chromatography, respectively. By using ELISA, the IgE-binding rates were detected for rBlo t 13 and its epitope peptides, as well as the cross-reactivity among rBlo t 13, rDer f 13, and rTyr p 13. The tertiary structure of rBlo t 13 was resolved using X-ray diffraction at 2.0 Å resolution. Using IgE-ELISA, the IgE binding rate of rBlo t 13 was 60 % with Blomia tropicalis-positive sera. In the experiments of ELISA for cross-reactivity with rBlo t 13 on solid phase, the inhibition rates were 65 %, 57 % and 63 % for rBlo t 13, rDer f 13, and rTyr p 13, respectively. The structure of Blo t 13 protein contains a β-barrel structure which is composed of 10 β strands and has 2 α helices at the end of the barrel. Comparison of the tertiary structures of rBlo t 13, rDer f 13, and rTyr p 13 revealed that the β-barrel structure is highly conserved, consistent with the alignment of amino acid sequences. We obtained the recombinant protein rBlo t 13, demonstrated its cross-reactivity with Der f 13 and Tyr p 13 due to their structural similarity.

PubMed: 37926306
DOI: 10.1016/j.ijbiomac.2023.127788

Experimental method

X-RAY DIFFRACTION (2 Å)