Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.4.22.65 (
Der p 1
)
346
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The potent allergenicity of
Der p 1
, a major allergen of the house dust mite Dermatophagoides pteronyssinus, is thought to be related to its cysteine protease activity. Therefore, there is considerable interest in developing a sensitive assay for measuring
Der p 1
activity to screen for specific inhibitors. This study demonstrates for the first time that the activity of
Der p 1
can be measured conveniently in a continuous rate assay with the fluorogenic substrate Boc-Gln-Ala-
Arg
-AMC (K(m) = 280 microM and kcat/K(m) = 4.6 x 10(3)/M/s).
...
PMID:A sensitive fluorescent assay for measuring the cysteine protease activity of Der p 1, a major allergen from the dust mite Dermatophagoides pteronyssinus. 989 50
Group 1 allergens of Dermatophagoides farinae (
Der f 1
) and D. pteronyssinus (
Der p 1
) dominate overall allergic responses in house dust mite allergy patients. The need for accurate identification and characterization of representative variants of group 1 allergens in any given geographic locality has been emphasized for development of appropriate allergen extracts. Regional amino acid sequence polymorphism has been described but the extent of this polymorphism is not well understood. Such data are completely absent for the USA and many other countries. Most previous studies used cDNA libraries generated by reverse transcriptase (RT-PCR) and/or primers amplifying shorter fragments of this gene. Using novel species-specific primers and direct PCR, we document group 1 allergen gene sequence polymorphism in populations of D. farinae and D. pteronyssinus from the USA and Pakistan. We report two novel introns (nt pos 87 and 291) in both species, and the absence of intron 3 in
Der p 1
. Thirteen silent and one novel non-synonymous mutation (Tryptophan W197 to
Arginine
R197) were detected in D. farinae. The potential medical significance of the latter mutation is discussed. Two haplotypes of the
Der f 1
gene were identified, haplotype 1 (63%) was more frequent than haplotype 2 (18%). Polymorphism in
Der f 1
displayed geographical localization, since both haplotypes were present in mite populations from Pakistan whereas haplotype 1 was observed only in the USA. In
Der p 1
, a silent mutation at nt (aa) position 1011(149) and four non-synonymous mutations at positions 589(50), 935(124), 971(136), 1268(215) were observed. These mutations were reported from many other geographic regions, suggesting that polymorphism in the
Der p 1
gene is panmictic. The extent of polymorphism in both genes is substantially lower than that reported previously (0.10-0.16% vs 0.31-0.49%), indicating the need for careful evaluation of potential polymerase errors in studies utilizing RT-PCR.
...
PMID:Group 1 Allergen Genes in Two Species of House Dust Mites, Dermatophagoides farinae and D. pteronyssinus (Acari: Pyroglyphidae): Direct Sequencing, Characterization and Polymorphism. 2549 56
Arginine
kinase (AK) was first identified as an allergen in the Indian-meal moth and subsequently shown to occur as allergen in various invertebrates and shellfish. The cDNA coding for AK from the house dust mite (HDM) species
Dermatophagoides pteronyssinus
, Der p 20, has been isolated, but no recombinant Der p 20 (rDer p 20) allergen has been produced and characterized so far. We report the expression of Der p 20 as recombinant protein in
Escherichia coli
. rDer p 20 was purified and shown to be a monomeric, folded protein by size exclusion chromatography and circular dichroism spectroscopy, respectively. Using AK-specific antibodies, Der p 20 was found to occur mainly in HDM bodies, but not in fecal particles. Thirty percent of clinically well-characterized HDM allergic patients (n = 98) whose immunoglobulin E (IgE) reactivity profiles had been determined with an extensive panel of purified HDM allergens (
Der f 1
, 2;
Der p 1
, 2, 4, 5, 7, 10, 11, 14, 15, 18, 21, 23 and 37) showed IgE reactivity to Der p 20. IgE reactivity to Der p 20 was more frequently associated with lung symptoms. AKs were detected in several invertebrates with specific antibodies and Der p 20 showed IgE cross-reactivity with AK from shrimp (
Litopenaeus vannamei
). Thus, Der p 20 is a cross-reactive HDM allergen and may serve as a diagnostic marker for HDM-induced lung symptoms such as asthma.
...
PMID:Expression in
Escherichia coli
and Purification of Folded rDer p 20, the Arginine Kinase From
Dermatophagoides pteronyssinus
: A Possible Biomarker for Allergic Asthma. 3319 83