Table 1.
Species-specific oligonucleotide primers used in nested amplification of the group 1 allergen gene (Der f 1 and Der p 1).
Table 2.
Exons, introns, and sequence polymorphism in the group 1 allergen-encoding gene of two species of house dust mites from Pakistan and the USA.
Figure 1.
Gene map of Der f 1 (A) and Der p 1 (B) allergens amplified by nested PCR.
UTR: untranslated regions; (numbers): nucleotide position for introns. The blank region with dashed outlines at exon 1 indicates partial 5′end of genes (given our sequences). T3/SP4 tails (see table 1) in primer sequences are not shown.
Figure 2.
Alignment of group 1 allergens (Cysteine proteases) of selected mite species.
Active site regions are shown in yellow, amino acid residues making 4C1 binding epitope (pink) and calcium binding epitope (green); “*”: identical, “:”: conserved and “.”: semi-conserved sites.
Figure 3.
I-TASSER result showing tertiary structure predictions for RS33 (Tryptophan variant) and RS31 (Arginine variant) of Der f 1 protein [36]–[38].
A: specimen RS33; B: specimen RS31.
Table 3.
Geographical polymorphism in the Der p 1 allergen.
Figure 4.
Maximum likelihood tree of the group 1 allergen protein of acariform mites.
For each node, nonparametric bootstrap support values (100 replicates) are indicated. The tree was inferred in RAxML ver.7.5.5 [39] using the WAGF model of amino acid evolution as found in PartitionFinder ver. 1.1.1 [40].
Table 4.
Percent identity matrix of aligned group1 allergens.
Figure 5.
Translated Der f 1 polypeptide aligned with cysteine proteases of other mite species:
Dermatophagoides pteronyssinus (Der p 1: present study, and U11695.1for Der p 1 to complete our partial signal peptide sequence), Euroglyphus maynei (Eur m 1:AAC82352.), Psoroptes ovis (Pso o 1:Q1EIQ3.1), Sarcoptes scabiei (Sar s 1: AAS93667.1), Acarus siro (Acr s: ABU50820.1), Blomia tropicalis (Blo t 1: AAQ24541.1) and Tyrophagus putrescentiae (Tyr p 1: ABM53753.1). Numbers inside triangles indicate the number of amino acids (aa). The “No data” box indicates missing 5′ ends.). AB034946 sequence was used to complete our partial Der f 1 signal peptide sequence.
Table 5.
Comparison of group 1 allergen conserved amino acid residues involved in 4C1mAb and Ca+ binding epitopes in eight mite species.