Biology:Phosphopantothenate—cysteine ligase
| Phosphopantothenate—cysteine ligase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC number | 6.3.2.5 | ||||||||
| CAS number | 9023-50-1 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
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In enzymology, a phosphopantothenate—cysteine ligase also known as phosphopantothenoylcysteine synthetase (PPCS) is an enzyme (EC 6.3.2.5) that catalyzes the chemical reaction which constitutes the second of five steps involved in the conversion of pantothenate to Coenzyme A. The reaction is:
- NTP + (R)-4'-phosphopantothenate + L-cysteine [math]\displaystyle{ \rightleftharpoons }[/math] NMP + diphosphate + N-[(R)-4'-phosphopantothenoyl]-L-cysteine
The nucleoside triphosphate (NTP) involved in the reaction varies from species to species. Phosphopantothenate—cysteine ligase from the bacterium Escherichia coli uses cytidine triphosphate (CTP) as an energy donor, whilst the human isoform uses adenosine triphosphate (ATP).[1]
Nomenclature
This enzyme belongs to the family of ligases, specifically those forming carbon-nitrogen bonds as acid-D-amino-acid ligases (peptide syntheses). The systematic name of this enzyme class is (R)-4'-phosphopantothenate:L-cysteine ligase. This enzyme is also called phosphopantothenoylcysteine synthetase.
Gene
 Generic protein structure example |
Phosphopantothenoylcysteine synthetase in humans is encoded by the PPCS gene.[2]
Protein structure
As of late 2007, 5 structures have been solved for this class of enzymes, with PDB accession codes 1P9O, 1U7U, 1U7W, 1U7Z, and 1U80.
References
- ↑ "Structure of human phosphopantothenoylcysteine synthetase at 2.3 A resolution". Structure 11 (8): 927–936. Aug 2003. doi:10.1016/S0969-2126(03)00146-1. PMID 12906824.
- ↑ "Entrez Gene: Phosphopantothenoylcysteine synthetase". https://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=retrieve&list_uids=79717.
Further reading
- Brown GM (1959). "The metabolism of pantothenic acid". J. Biol. Chem. 234 (2): 370–8. doi:10.1016/S0021-9258(18)70307-4. PMID 13630913.
- "Phosphopantothenoylcysteine synthetase from Escherichia coli Identification and characterization of the last unidentified coenzyme A biosynthetic enzyme in bacteria". J. Biol. Chem. 276 (17): 13513–6. 2001. doi:10.1074/jbc.C100033200. PMID 11278255.
- Kupke T (2002). "Molecular characterization of the 4'-phosphopantothenoylcysteine synthetase domain of bacterial dfp flavoproteins". J. Biol. Chem. 277 (39): 36137–45. doi:10.1074/jbc.M206188200. PMID 12140293.
External links
- PDBe-KB provides an overview of all the structure information available in the PDB for Human Phosphopantothenate—cysteine ligase
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