Phytanoyl-CoA dioxygenase
Encyclopedia
In enzymology, a phytanoyl-CoA dioxygenase is an enzyme
that catalyzes
the chemical reaction
The three substrates
of this enzyme are phytanoyl-CoA
, 2-oxoglutarate, and O2
, whereas its three products
are 2-hydroxyphytanoyl-CoA, succinate, and CO2
.
This enzyme belongs to the family of oxidoreductase
s, which act on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2 with 2-oxoglutarate as one donor, and incorporation of one atom of oxygen into each donor.
and is required for the alpha-oxidation of branched chain fatty acids (e.g phytanic acid
) in peroxisomes. PHYH deficiency results in the accumulation of large tissue stores of phytanic acid
and is the major cause of Refsum disease.
has been solved for this class of enzymes, with the PDB
accession code .
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that catalyzes
Catalysis
Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in multiple chemical transformations....
the chemical reaction
Chemical reaction
A chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Chemical reactions can be either spontaneous, requiring no input of energy, or non-spontaneous, typically following the input of some type of energy, such as heat, light or electricity...
- phytanoyl-CoA + 2-oxoglutarate + O2
2-hydroxyphytanoyl-CoA + succinate + CO2
The three substrates
Substrate (biochemistry)
In biochemistry, a substrate is a molecule upon which an enzyme acts. Enzymes catalyze chemical reactions involving the substrate. In the case of a single substrate, the substrate binds with the enzyme active site, and an enzyme-substrate complex is formed. The substrate is transformed into one or...
of this enzyme are phytanoyl-CoA
Phytanoyl-CoA
Phytanoyl-CoA is a derivative of phytanic acid.-See also:* Phytanoyl-CoA hydroxylase...
, 2-oxoglutarate, and O2
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
, whereas its three products
Product (chemistry)
Product are formed during chemical reactions as reagents are consumed. Products have lower energy than the reagents and are produced during the reaction according to the second law of thermodynamics. The released energy comes from changes in chemical bonds between atoms in reagent molecules and...
are 2-hydroxyphytanoyl-CoA, succinate, and CO2
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
.
This enzyme belongs to the family of oxidoreductase
Oxidoreductase
In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule to another...
s, which act on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2 with 2-oxoglutarate as one donor, and incorporation of one atom of oxygen into each donor.
Nomenclature
The systematic name of this enzyme class is phytanoyl-CoA, 2-oxoglutarate:oxygen oxidoreductase (2-hydroxylating). This enzyme is also called phytanoyl-CoA hydroxylase.Examples
In humans, phytanoyl-CoA hydroxylase is encoded by the PHYH (aka PAHX) geneGene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
and is required for the alpha-oxidation of branched chain fatty acids (e.g phytanic acid
Phytanic acid
Phytanic acid is a branched chain fatty acid that humans can obtain through the consumption of dairy products, ruminant animal fats, and certain fish. Western diets are estimated to provide 50-100 mg of phytanic acid per day...
) in peroxisomes. PHYH deficiency results in the accumulation of large tissue stores of phytanic acid
Phytanic acid
Phytanic acid is a branched chain fatty acid that humans can obtain through the consumption of dairy products, ruminant animal fats, and certain fish. Western diets are estimated to provide 50-100 mg of phytanic acid per day...
and is the major cause of Refsum disease.
Structural studies
As of late 2007, only one structureTertiary structure
In biochemistry and molecular biology, the tertiary structure of a protein or any other macromolecule is its three-dimensional structure, as defined by the atomic coordinates.-Relationship to primary structure:...
has been solved for this class of enzymes, with the PDB
Protein Data Bank
The Protein Data Bank is a repository for the 3-D structural data of large biological molecules, such as proteins and nucleic acids....
accession code .