A sensitive fluorescent assay for measuring the cysteine protease activity of Der p 1, a major allergen from the dust mite Dermatophagoides pteronyssinus.
- Division of Molecular and Clinical Immunology, Faculty of Medicine and Health Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, UK.
Abstract
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).
