PCCB
PCCB (propionyl-CoA carboxylase subunit beta) is one of the two subunits of the biotin-dependent enzyme propionyl-CoA carboxylase (PCC) in the mitochondrial matrix. It transfers the carboxyl group from carboxylated biotin to propionyl-CoA, a step in the catabolism of odd chain fatty acids and several amino acids. Browse Assay Genie's current range of PCCB research reagents below, or read on for the biology behind the target.
PCCB is the beta subunit of propionyl-CoA carboxylase (PCC), a biotin-dependent mitochondrial enzyme involved in the catabolism of odd chain fatty acids, the branched-chain amino acids isoleucine and valine, threonine, methionine and other metabolites. PCC catalyses the carboxylation of propionyl-CoA (propanoyl-CoA) to D-methylmalonyl-CoA, also described as (S)-methylmalonyl-CoA. The reaction is split between the two subunits: the alpha subunit catalyses the ATP-dependent carboxylation of the biotin carried by its biotin carboxyl carrier (BCC) domain, and the beta subunit then transfers the carboxyl group from carboxylated biotin to propionyl-CoA.
PCC also acts significantly on butyryl-CoA (butanoyl-CoA), which is converted to ethylmalonyl-CoA at a much lower rate. Other minor substrates include (2E)-butenoyl-CoA, also known as crotonoyl-CoA. The enzyme probably acts as a dodecamer of six alpha and six beta subunits. The PCCB protein is localised to the mitochondrial matrix and belongs to the AccD/PCCB family. In mouse and rat the orthologous gene is Pccb.
The PCCB gene encodes the beta subunit, and the HGNC groups it with the propionyl-CoA carboxylase subunits. It was previously named propionyl Coenzyme A carboxylase, beta polypeptide. Multiple transcript variants encoding different isoforms have been described. Defects in the PCCB gene are a cause of propionic acidemia type II (PA-2), which makes the protein a common reference point for studies of propionate metabolism and mitochondrial enzyme function.
PCCB carries the carboxyl transfer step that converts propionyl-CoA to methylmalonyl-CoA, making it central to propionyl-CoA catabolism.
PCC participates in breakdown of isoleucine, threonine, methionine and valine, so PCCB is relevant to branched-chain amino acid pathway studies.
The enzyme is involved in the catabolism of odd chain fatty acids, which yield propionyl-CoA as an end product.
Defects in the PCCB gene cause propionic acidemia type II, supporting disease mechanism and genotype studies.
PCCB is the beta subunit of propionyl-CoA carboxylase. After the alpha subunit carboxylates biotin in an ATP-dependent step, the beta subunit transfers the carboxyl group from carboxylated biotin to propionyl-CoA, producing methylmalonyl-CoA in the mitochondrial matrix.
The HGNC full name is propionyl-CoA carboxylase subunit beta, and the UniProt name is propionyl-CoA carboxylase beta chain, mitochondrial. The previous name was propionyl Coenzyme A carboxylase, beta polypeptide. Multiple transcript variants encoding different isoforms have been reported for the gene.
Defects in the PCCB gene are a cause of propionic acidemia type II (PA-2). Orthologues exist in mouse and rat, both named Pccb. Check the datasheet of any product for its validated reactivity.
Other carboxylase subunits and enzymes of propionyl-CoA and branched-chain amino acid metabolism with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P05166; product specifications from Assay Genie datasheets.