Dihydrolipoyl transacetylase (or dihydrolipoamide acetyltransferase) is the structural and catalytic core of the multienzyme pyruvate dehydrogenase complex, playing a crucial role in the architecture of the complex. All dihydrolipoyl transacetylases have a unique multidomain structure consisting of (from N to C); 3 lipoyl domains; and interaction domain; and the catalytic domain (see the domain architecture at Pfam). Interestingly all the domains are connected by disordered, low complexity linker regions.
The catalytic domains are assembled into trimers, and in some organisms eight trimers are arranged into a hollow truncated cube. The active site is located in the subunit interface.
