ACE2 or ACEH, angiotensin-converting enzyme 2, a homolog of angiotensin-converting enzyme, is a novel zinc metallopeptidase with specificity, tissue distribution, and function distinct from those of ACE. ACE2 may play a unique role in the renin-angiotensin system and mediate cardiovascular and renal function. The SensoLyte® 390 ACE2 Activity Assay Kit provides a convenient assay for high throughput screening of ACE2 enzyme inhibitors and inducers using a Mc-Ala/Dnp fluorescence resonance energy transfer (FRET) peptide. In the FRET peptide, the fluorescence of Mc-Ala is quenched by Dnp. Upon cleavage into two separate fragments by ACE2, the fluorescence of Mc-Ala is recovered, and can be monitored at excitation/emission = 330/390 nm. This assay can detect the activity of subnanogram level of ACE2. Assays are performed in a convenient 96-well microplate format.