Palmitoylation is the covalent attachment of fatty acids, such as palmitic acid, to cysteine (S-palmitoylation) and less frequently to serine and threonine (O-palmitoylation) residues of proteins, which are typically membrane proteins. The precise function of palmitoylation depends on the particular protein being considered. Palmitoylation enhances the hydrophobicity of proteins and contributes to their membrane association. Palmitoylation also appears to play a significant role in subcellular trafficking of proteins between membrane compartments, as well as in modulating protein–protein interactions. In contrast to prenylation and myristoylation, palmitoylation is usually reversible (because the bond between palmitic acid and protein is often a thioester bond). The reverse reaction in mammalian cells is catalyzed by acyl-protein thioesterases (APTs) in the cytosol and palmitoyl protein thioesterases in lysosomes. Because palmitoylation is a dynamic, post-translational process, it is believed to be employed by the cell to alter the subcellular localization, protein–protein interactions, or binding capacities of a protein.
Palmitoyl-CoA is an acyl-CoA thioester. It is an "activated" form of palmitic acid and can be transported into the mitochondrial matrix by the carnitine shuttle system, and once inside can participate in beta-oxidation. Alternatively, palmitoyl-CoA is used as a substrate in the biosynthesis of sphingosine.
Carnitine palmitoyltransferase I (CPT1) also known as carnitine acyltransferase I, CPTI, CAT1, CoA:carnitine acyl transferase (CCAT), or palmitoylCoA transferase I, is a mitochondrial enzyme responsible for the formation of acyl carnitines by catalyzing the transfer of the acyl group of a long-chain fatty acyl-CoA from coenzyme A to l-carnitine. The product is often Palmitoylcarnitine, but other fatty acids may also be substrates. It is part of a family of enzymes called carnitine acyltransferases. This "preparation" allows for subsequent movement of the acyl carnitine from the cytosol into the intermembrane space of mitochondria.
Palmitoyl-CoA hydrolase (EC 3.1.2.2) is an enzyme in the family of hydrolases that specifically acts on thioester bonds. It catalyzes the hydrolysis of long chain fatty acyl thioesters of acyl carrier protein or coenzyme A to form free fatty acid and the corresponding thiol:
Palmitoyl protein hydrolase/thioesterases is an enzyme (EC 3.1.2.22) that removes thioester-linked fatty acyl groups such as palmitate from modified cysteine residues in proteins or peptides during lysosomal degradation. It catalyzes the reaction
In enzymology, a 1-acylglycerol-3-phosphate O-acyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a 2-acylglycerol-3-phosphate O-acyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a 2-acylglycerol O-acyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a 2-acylglycerophosphocholine O-acyltransferase is an enzyme that catalyzes the chemical reaction
Carnitine O-octanoyltransferase is a member of the transferase family, more specifically a carnitine acyltransferase, a type of enzyme which catalyzes the transfer of acyl groups from acyl-CoAs to carnitine, generating CoA and an acyl-carnitine. The systematic name of this enzyme is octanoyl-CoA:L-carnitine O-octanoyltransferase. Other names in common use include medium-chain/long-chain carnitine acyltransferase, carnitine medium-chain acyltransferase, easily solubilized mitochondrial carnitine palmitoyltransferase, and overt mitochondrial carnitine palmitoyltransferase. Specifically, CROT catalyzes the chemical reaction:
In enzymology, a dolichol O-acyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a glycerol-3-phosphate O-acyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a glycine N-acyltransferase (GLYAT), also known as acyl-CoA:glycine N-acyltransferase (ACGNAT), is an enzyme that catalyzes the chemical reaction
In enzymology, a glycoprotein N-palmitoyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a glycoprotein O-fatty-acyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a [myelin-proteolipid] O-palmitoyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a retinol O-fatty-acyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a serine C-palmitoyltransferase (EC 2.3.1.50) is an enzyme that catalyzes the chemical reaction:
In enzymology, sphingosine N-acyltransferases (ceramide synthases (CerS), EC 2.3.1.24) are enzymes that catalyze the chemical reaction of synthesis of ceramide:
Fatty acyl-CoA esters are fatty acid derivatives formed of one fatty acid, a 3'-phospho-AMP linked to phosphorylated pantothenic acid (vitamin B5) and cysteamine.
