DBT
DBT is the lipoamide acyltransferase (E2) component of the mitochondrial branched-chain alpha-keto acid dehydrogenase complex. Also known as BCOADC-E2, BCKAD-E2 and BCKDH-E2, it transfers acyl groups to coenzyme A during branched-chain amino acid breakdown. Browse Assay Genie's current range of DBT research reagents below, or read on for the biology behind the target.
The branched-chain alpha-keto dehydrogenase complex (BCKD) catalyses the overall conversion of alpha-keto acids to acyl-CoA and CO2. It contains multiple copies of three enzymatic components: branched-chain alpha-keto acid decarboxylase (E1), lipoamide acyltransferase (E2) and lipoamide dehydrogenase (E3). DBT provides the E2 activity. Its catalytic role within the complex is to accept the acyl groups generated by the E1 decarboxylase and transfer them to coenzyme A.
BCKD is an inner-mitochondrial enzyme complex involved in the breakdown of the branched-chain amino acids isoleucine, leucine and valine. The complex is thought to be built around a core of 24 transacylase (E2) subunits, with associated decarboxylase (E1), dehydrogenase (E3) and regulatory subunits. The DBT protein is located in the mitochondrial matrix and belongs to the 2-oxoacid dehydrogenase family. The mouse ortholog is Dbt, and HGNC classes the gene within the branched chain alpha-keto acid dehydrogenase complex subunits and the acyltransferases.
The DBT gene takes its name from dihydrolipoamide branched chain transacylase, and earlier HGNC nomenclature referred to it as the E2 component of the branched chain keto acid dehydrogenase complex. Mutations in this gene result in maple syrup urine disease, type 2. Alternatively spliced transcript variants have been described, but their biological validity has not been determined, which is worth bearing in mind when interpreting results from DBT expression studies.
DBT is part of the BCKD complex that breaks down isoleucine, leucine and valine, making it a core component for studying this catabolic pathway.
Mutations in the DBT gene cause maple syrup urine disease, type 2, so the protein is relevant to studies of this inherited metabolic disorder.
As the E2 core subunit of a multi-component mitochondrial complex, DBT is used to examine how E1, E2 and E3 activities are organised.
DBT belongs to the 2-oxoacid dehydrogenase family, supporting comparative work on acyltransferase function across alpha-keto acid dehydrogenase complexes.
DBT is the lipoamide acyltransferase (E2) component of the branched-chain alpha-keto acid dehydrogenase complex. It accepts acyl groups generated by the E1 decarboxylase component and transfers them to coenzyme A, contributing to the conversion of alpha-keto acids to acyl-CoA and CO2 in the mitochondrial matrix.
DBT is also called BCOADC-E2, BCKAD-E2 and BCKDH-E2. Its full name is dihydrolipoamide branched chain transacylase E2, and the enzyme carries the EC number 2.3.1.168. UniProt describes it as the lipoamide acyltransferase component of the branched-chain alpha-keto acid dehydrogenase complex, mitochondrial.
Mutations in the DBT gene result in maple syrup urine disease, type 2. A mouse ortholog, Dbt, is recognised. Researchers working in other species should check the datasheet of any product for its validated reactivity.
Other BCKD complex subunits, regulators and mitochondrial enzymes involved in branched-chain amino acid metabolism.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P11182; product specifications from Assay Genie datasheets.