Substrate-Dependent Modulation of SIRT2 by a Fluorescent Probe, 1-Aminoanthracene.

ABSTRACT: Sirtuin isoform 2 (SIRT2) is an enzyme that catalyzes the removal of acyl groups from lysine residues. SIRT2's catalytic domain has a hydrophobic tunnel where its substrate acyl groups bind. Here, we report that the fluorescent probe 1-aminoanthracene (AMA) binds within SIRT2's hydrophobic tunnel in a substrate-dependent manner. AMA's interaction with SIRT2 was characterized by its enhanced fluorescence upon protein binding (>10-fold). AMA interacted weakly with SIRT2 alone in solution (K_d = 37 μM). However, when SIRT2 was equilibrated with a decanoylated peptide substrate, AMA's affinity for SIRT2 was enhanced ∼10-fold (K_d = 4 μM). The peptide's decanoyl chain and AMA co-occupied SIRT2's hydrophobic tunnel when bound to the protein. In contrast, binding

SUBMITTER: Bi D 

PROVIDER: S-EPMC7880049 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature