کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5916980 1163765 2013 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Structural and bioinformatic analysis of the kiwifruit allergen Act d 11, a member of the family of ripening-related proteins
ترجمه فارسی عنوان
تجزیه و تحلیل ساختاری و بیوانفورماتیک آلرژن کیوی آلوژن 11 قانون، عضو خانواده پروتئین های مربوط به رسیدن
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شناسی مولکولی
چکیده انگلیسی


- We determined structure of kiwifruit allergen Act d 11.
- Act d 11 and Bet v1 have a very similar fold.
- Act d 11 has smaller ligand-binding cavity than PR-10 allergens.
- Gly-rich loop may cause the IgE cross-reactivity between Bet v 1 and Act d 11.

The allergen Act d 11, also known as kirola, is a 17 kDa protein expressed in large amounts in ripe green and yellow-fleshed kiwifruit. Ten percent of all kiwifruit-allergic individuals produce IgE specific for the protein. Using X-ray crystallography, we determined the first three-dimensional structures of Act d 11, produced from both recombinant expression in Escherichia coli and from the natural source (kiwifruit). While Act d 11 is immunologically correlated with the birch pollen allergen Bet v 1 and other members of the pathogenesis-related protein family 10 (PR-10), it has low sequence similarity to PR-10 proteins. By sequence Act d 11 appears instead to belong to the major latex/ripening-related (MLP/RRP) family, but analysis of the crystal structures shows that Act d 11 has a fold very similar to that of Bet v 1 and other PR-10 related allergens regardless of the low sequence identity. The structures of both the natural and recombinant protein include an unidentified ligand, which is relatively small (about 250 Da by mass spectrometry experiments) and most likely contains an aromatic ring. The ligand-binding cavity in Act d 11 is also significantly smaller than those in PR-10 proteins. The binding of the ligand, which we were not able to unambiguously identify, results in conformational changes in the protein that may have physiological and immunological implications. Interestingly, the residue corresponding to Glu45 in Bet v 1 (Glu46), which is important for IgE binding to the birch pollen allergen, is conserved in Act d 11, even though it is not in other allergens with significantly higher sequence identity to Bet v 1. We suggest that the so-called Gly-rich loop (or P-loop), which is conserved in all PR-10 allergens, may be responsible for IgE cross-reactivity between Bet v 1 and Act d 11.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Molecular Immunology - Volume 56, Issue 4, 31 December 2013, Pages 794-803
نویسندگان
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