The crystal structure of recombinant proDer p 1, a major house dust mite proteolytic allergen.
Allergy to house dust mite is among the most prevalent allergic diseases worldwide. Most house dust mite allergic patients react to Der p 1 from Dermatophagoides pteronyssinus, which is a cysteine protease. To avoid heterogeneity in the sample used for crystallization, a modified recombinant molecule was produced. The sequence of the proDer p 1 allergen was modified to reduce glycosylation and to abolish enzymatic activity. The resulting rproDer p 1 preparation was homogenous and stable and yielded crystals diffracting to a resolution of 1.61 A. The active site is located in a large cleft on the surface of the molecule. The 80-aa pro-peptide adopts a unique fold that interacts with the active site cleft and a substantial adjacent area on the mature region, excluding access to the cleft and the active site. Studies performed using crossed-line immunoelectrophoresis and IgE inhibition experiments indicated that several epitopes are covered by the pro-peptide and that the epitopes on the recombinant mature molecule are indistinguishable from those on the natural one. The structure confirms previous results suggesting a preference for aliphatic residues in the important P2 position in substrates. Sequence variations in related species are concentrated on the surface, which explains the existence of cross-reacting and species-specific antibodies. This study describes the first crystal structure of one of the clinically most important house dust mite allergens, the cysteine protease Der p 1.
Meno
Kåre
K
ALK-Abelló A/S, Research Department, Hørsholm, Denmark. kme@dk.alk-abello.com
Thorsted
Peter B
PB
Ipsen
Henrik
H
Kristensen
Ole
O
Larsen
Jørgen N
JN
Spangfort
Michael D
MD
Gajhede
Michael
M
Lund
Kaare
K
D000485:Allergens / Q000737:chemistry*; D000818:Animals; D060829:Arthropod Proteins; D001665:Binding Sites; D003429:Cross Reactions; D018360:Crystallography, X-Ray; D000939:Epitopes; D005818:Genetic Engineering; D008958:Models, Molecular; D015394:Molecular Structure; D011487:Protein Conformation; D011498:Protein Precursors / Q000737:chemistry*; D039981:Pyroglyphidae / Q000737:chemistry / Q000276:immunology; D011994:Recombinant Proteins; D013045:Species Specificity; D013379:Substrate Specificity
D000485:Allergens; D060829:Arthropod Proteins; D000939:Epitopes; C504325:ProDer p 1 allergen, Dermatophagoides pteronyssinus; D011498:Protein Precursors; D011994:Recombinant Proteins