Carnitine-O-palmitoyl transferase , also carnitine acyltransferase or carnitine palmitoyl transferase , abbr. CPT ( EC 2.3.1.21 ) is an enzyme from the acyltransferase group (type of transferase ) that catalyzes the transfer of an acyl group from an acyl-CoA molecule to a carnitine molecule (with the formation of an acylated carnitine - carnitine-COR (where R is the residue of fatty acids, in particular palmitoyl) and coenzyme A molecule (CoA-SH)) and vice versa. Refers to integral proteins , located on the outer side of the outer membrane (on the cytoplasmic side) and the inner side of the inner membrane of mitochondria (on the side of the matrix). It is an integral part of the carnitine transport system . It has several different forms. Participates in the degradation of fatty acids.
| Carnitine O-Palmitoyltransferase | |
|---|---|
 The structure of carnitine-O-palmitoyltransferase [1] . | |
| Identifiers | |
| Symbol | Carn_acyltransf |
| Pfam | PF00755 |
| Pfam clan | CL0149 |
| Interpro | IPR000542 |
| PROSITE | PDOC00402 |
| SCOP | 1ndi |
| SUPERFAMILY | 1ndi |
| OPM superfamily | 183 |
| OPM protein | 2h3u |
| Available protein structures | |
| Pfam | the structure |
| PDB | RCSB PDB ; PDBe ; PDBj |
| PDBsum | 3D model |
Transfer Mechanism
It is presented in the form of equations:
R-CO ~ SCoA + carnitine ↔ carnitine-COR + CoA-SH
The reaction is reversible. The enzyme located on the outer membrane ( carnitine-palmitoyltransferase I , CPT1) of mitochondria catalyzes a direct reaction, and accordingly the reverse, however, it is located on the inner side of the inner membrane of mitochondria (carnitine-palmitoyltransferase II, CPT2)
Human Forms
There are 4 different forms of this enzyme that are found in the human body:
- CPT1A
- CPT1B
- CPT1C
- CPT2
Notes
- ↑ Jogl G., Tong L. Crystal structure of carnitine acetyltransferase and implications for the catalytic mechanism and fatty acid transport (Eng.) // Cell : journal. - Cell Press 2003 .-- January ( vol. 112 , no. 1 ). - P. 113—122 . - DOI : 10.1016 / S0092-8674 (02) 01228-X . - PMID 12526798 .