Tae Hyeon Yoo

Recent development of highly sensitive protease assay methods: Signal amplification through enzyme cascades

Proteases are involved in almost all biological processes, and therefore, aberrant activity of many of these enzymes is an important indicator of disease. Various methods have been developed to analyze protease activity, among which, protease assays based on resonance energy transfer are currently used most widely. However, quantitative methods with relatively higher sensitivity are needed, especially for disease diagnosis at early stages. One of the strategies to achieve higher sensitivity is to implement signal amplification of the protease activity. In this review, we briefly summarize the protease assay methods based on resonance energy transfer, and then elaborate the efforts to develop sensitive protease assays through signal amplification by using enzyme cascades.

A novel protease activity assay method based on an engineered autoinhibited protein using an enzyme-linked immunoassay

Proteases are involved in various biological phenomena, and their aberrant activity can be an important indicator of disease. Thus, various methods have been developed to analyze the activities of proteases, but their wide application has been hampered because each method has drawbacks. In this report, we propose a new protease assay method based on an engineered autoinhibited protein and enzyme-linked immunoassay (ELISA) in which a protease of interest activates the autoinhibited protein and the signal is amplified via ELISA. Using this concept a sensitive assay method for MMP2 and caspase-3 was developed. The limit of detection for the two proteases was as low as 7 pM for MMP2 and 0.1 pM for caspase-3. The autoinhibited protein is designed modularly, and the new platform is general enough for the development of assay methods for other proteases with minimal modification.

Correction: Engineering β-lactamase zymogens for use in protease activity assays

Correction for ‘Engineering β-lactamase zymogens for use in protease activity assays’ by Hajin Kim et al., Chem. Commun., 2014, 50, 10155–10157.