Structural highlights
9uhr is a 3 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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| Method: | Electron Microscopy, Resolution 2.48Å |
| Ligands: | , , , , |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Disease
PCCB_HUMAN Propionic acidemia. The disease is caused by variants affecting the gene represented in this entry.
Function
PCCB_HUMAN This is one of the 2 subunits of the biotin-dependent propionyl-CoA carboxylase (PCC), a mitochondrial enzyme involved in the catabolism of odd chain fatty acids, branched-chain amino acids isoleucine, threonine, methionine, and valine and other metabolites (PubMed:15890657, PubMed:6765947). Propionyl-CoA carboxylase catalyzes the carboxylation of propionyl-CoA/propanoyl-CoA to D-methylmalonyl-CoA/(S)-methylmalonyl-CoA (PubMed:15890657, PubMed:6765947). Within the holoenzyme, the alpha subunit catalyzes the ATP-dependent carboxylation of the biotin carried by the biotin carboxyl carrier (BCC) domain, while the beta subunit then transfers the carboxyl group from carboxylated biotin to propionyl-CoA (By similarity). Propionyl-CoA carboxylase also significantly acts on butyryl-CoA/butanoyl-CoA, which is converted to ethylmalonyl-CoA/(2S)-ethylmalonyl-CoA at a much lower rate (PubMed:6765947). Other alternative minor substrates include (2E)-butenoyl-CoA/crotonoyl-CoA (By similarity).[UniProtKB:P79384][UniProtKB:Q168G2][1] [2]
Publication Abstract from PubMed
Propionyl-CoA carboxylase (PCC) is a biotin-dependent mitochondrial enzyme responsible for propionyl-CoA catabolism. Deficiencies in human PCC (hPCC) cause propionic acidemia, a severe metabolic disorder driven by toxic metabolite accumulation. Despite its therapeutic relevance, the structural basis of hPCC's catalytic function remains unresolved. Here, we present high-resolution cryo-EM structures of hPCC in four distinct states, unliganded, ADP-, AMPPNP-, and ATP-bound/substrate-bound, capturing the full trajectory of the biotin carboxyl carrier protein (BCCP) domain as it translocates between active sites. Our results reinforce the crucial role of nucleotide-gated B-lid subdomain in synchronizing catalysis through coupling with BCCP movement. Structural and biochemical analysis of 10 disease-associated variants reveals how mutations disrupt key domain interfaces and dynamic motions required for activity. These new insights define the mechanistic principles governing hPCC functions, establish a structural framework for understanding PCC-related disorders, and lay the groundwork for future efforts to engineer functional replacements or modulators for metabolic therapy.
Nanoscale conformational dynamics of human propionyl-CoA carboxylase.,Yan H, Ni F, Wang Q, Ma J Structure. 2025 Nov 5:S0969-2126(25)00396-X. doi: 10.1016/j.str.2025.10.009. PMID:41197621[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Jiang H, Rao KS, Yee VC, Kraus JP. Characterization of four variant forms of human propionyl-CoA carboxylase expressed in Escherichia coli. J Biol Chem. 2005 Jul 29;280(30):27719-27. PMID:15890657 doi:10.1074/jbc.M413281200
- ↑ Kalousek F, Darigo MD, Rosenberg LE. Isolation and characterization of propionyl-CoA carboxylase from normal human liver. Evidence for a protomeric tetramer of nonidentical subunits. J Biol Chem. 1980 Jan 10;255(1):60-5 PMID:6765947
- ↑ Yan H, Ni F, Wang Q, Ma J. Nanoscale conformational dynamics of human propionyl-CoA carboxylase. Structure. 2025 Nov 5:S0969-2126(25)00396-X. PMID:41197621 doi:10.1016/j.str.2025.10.009
