The DBT gene provides instructions for making part of an enzyme complex (a group of enzymes that work together) called branched-chain alpha-keto acid dehydrogenase, or BCKD. Specifically, the protein produced from the DBT gene forms a critical part of the enzyme complex called the E2 component.
The BCKD enzyme complex is responsible for one step in the normal breakdown of three protein building blocks (amino acids). These amino acids—leucine, isoleucine, and valine—are obtained from the diet. They are present in many kinds of food, particularly protein-rich foods such as milk, meat, and eggs. The BCKD enzyme complex is active in mitochondria, which are specialized structures inside cells that serve as energy-producing centers. The breakdown of leucine, isoleucine, and valine produces molecules that can be used for energy.