# A homogeneous time-resolved fluorescence screen to identify SIRT2 deacetylase and defatty-acylase inhibitors

## TL;DR

Researchers developed a new screening method to find molecules that inhibit SIRT2 enzyme activity, which is linked to various diseases.

## Contribution

A novel HTRF-based high-throughput screen was developed to identify dual inhibitors of SIRT2's deacetylase and demyristoylase activities.

## Key findings

- A small molecule was identified that inhibits both deacetylase and demyristoylase activities of SIRT2.
- Two fragments of the molecule inhibit SIRT2 independently: a halogenated phenol and a tricyclic thiazolobenzimidazole.
- The screen also identified multiple inhibitors specific to SIRT2's deacetylase activity.

## Abstract

Human sirtuin-2 (SIRT2) has emerged as an attractive drug target for a variety of diseases. The enzyme is a deacylase that can remove chemically different acyl modifications from protein lysine residues. Here, we developed a high-throughput screen based on a homogeneous time-resolved fluorescence (HTRF) binding assay to identify inhibitors of SIRT2’s demyristoylase activity, which is uncommon among many ligands that only affect its deacetylase activity. From a test screen of 9600 compounds, we identified a small molecule that inhibited SIRT2’s deacetylase activity (IC50 = 7 μM) as well as its demyristoylase activity (IC50 = 37 μM). The inhibitor was composed of two small fragments that independently inhibited SIRT2: a halogenated phenol fragment inhibited its deacetylase activity, and a tricyclic thiazolobenzimidazole fragment inhibited its demyristoylase activity. The high-throughput screen also detected multiple deacetylase-specific SIRT2 inhibitors.