Lipoyl deglutarylation by ABHD11 regulates mitochondrial and T cell metabolism

Abstract

Glutarate is an intermediate of amino acid catabolism and an important metabolite for reprogramming T cell immunity. Glutarate exerts its effects either by directly inhibiting metabolite-dependent enzymes or through conjugation to substrates. Intriguingly, glutarylation can occur on protein and nonprotein substrates, but our understanding of these distinct glutaryl modifications is in its infancy. Here we uncover ABHD11 as a noncanonical deglutarylating enzyme critical for maintaining the tricarboxylic acid (TCA) cycle. Mechanistically, we find ABHD11 removes glutaryl adducts from lipoate—an essential fatty acid modification required for the TCA cycle. Loss of ABHD11 results in the accumulation of glutaryl–lipoyl adducts that drive an adaptive program, involving 2-oxoglutarate accumulation, that rewires mitochondrial metabolism. Functionally, this role of ABHD11 influences the metabolic programming of human CD8+ T cells. Therefore, our findings reveal lipoyl glutarylation as a reversible modification that regulates the TCA cycle. (Figure presented.)