Coenzyme A binding sites induce proximal acylation across protein families

ABSTRACT: Lysine acylations, such as acetylation, succinylation, or glutarylation, are post-translational modifications that regulate protein function. In mitochondria, lysine acylation is predominantly non-enzymatic and only a specific subset of the proteome has been identified as acylated. Coenzyme A (CoA), a metabolite required in several metabolic pathways, can act as an acyl group carrier via a thioester bond. However, what controls the acylation of lysine residues in the mitochondria remains poorly understood. Using published datasets, we found that proteins with a CoA-binding site are more likely to be acetylated, succinylated, and glutarylated. Using computational modeling, we discovered that, in CoA-binding proteins, lysine residues near the CoA-binding pocket are more likely to be acylated than those far away from the CoA-binding pocket. We hypothesized that acyl-CoA binding enhances the acylation of nearby lysine residues. To experimentally test this hypothesis, we used enoyl-CoA hydratase short chain 1 (ECHS1), a mitochondrial protein with a CoA-binding pocket, and co-incubated ECHS1 with succinyl-CoA and CoA. Using mass spectrometry, we found that succinyl-CoA induced widespread lysine succinylation and that CoA competitively inhibited ECHS1 succinylation. In addition, CoA-induced inhibition at a particular lysine site was inversely correlated with the distance between this lysine residue and the CoA-binding pocket. This indicated that CoA acts as a competitive inhibitor of ECHS1 succinylation by binding to the CoA-binding pocket. Together, this study suggests proximal acylation at protein CoA-binding sites is a primary mechanism for lysine acylation in the mitochondria.

INSTRUMENT(S): TripleTOF 6600

ORGANISM(S): Homo Sapiens (ncbitaxon:9606)

SUBMITTER: Birgit Schilling  

PROVIDER: MSV000089448 | MassIVE | Mon May 09 17:54:00 BST 2022

SECONDARY ACCESSION(S): PXD033787

REPOSITORIES: MassIVE