The enzyme 4-phytase ()
catalyzes
Catalysis () is the increase in rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quick ...
the following reaction:
:
''myo''-inositol hexakisphosphate + H
2O
1D-''myo''-inositol 1,2,3,5,6-pentakisphosphate +
phosphate
Phosphates are the naturally occurring form of the element phosphorus.
In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthop ...
''myo''-Inositol hexakisphosphate is also known as
phytic acid
Phytic acid is a six-fold dihydrogenphosphate ester of inositol (specifically, of the ''myo'' isomer), also called inositol hexaphosphate, inositol hexakisphosphate (IP6) or inositol polyphosphate. At physiological pH, the phosphates are partia ...
.
These enzymes belongs to the family of
hydrolase
In biochemistry, hydrolases constitute a class of enzymes that commonly function as biochemical catalysts that use water to break a chemical bond:
:\ce \quad \xrightarrowtext\quad \ce
This typically results in dividing a larger molecule into s ...
s, specifically those acting on phosphoric
monoester
In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distinct ...
bonds. The
systematic name
A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature.
A semisystematic name or semitrivi ...
of this enzyme class is ''myo''-inositol-hexakisphosphate 4-phosphohydrolase. Other names in common use include 6-phytase (name based on 1
L-numbering system and not 1
D-numbering) and phytate 6-phosphatase.
Enzymes of this type participate in
inositol phosphate
Inositol phosphates are a group of mono- to hexaphosphorylated inositols. Each form of inositol phosphate is distinguished by the number and position of the phosphate group on the inositol ring.
* inositol monophosphate (IP)
* inositol bisphospha ...
metabolism.
See also
*
3-phytase
The enzyme 3-phytase (EC 3.1.3.8) catalyzes the reaction
: ''myo''-inositol hexakisphosphate + H2O = 1D-''myo''-inositol 1,2,4,5,6-pentakisphosphate + phosphate
''myo''-Inositol hexakisphosphate is also known as phytic acid.
These enzymes belon ...
(1-phytase)
*
5-phytase
The enzyme 5-phytase (EC 3.1.3.72) catalyzes the reaction
:''myo''-inositol hexakisphosphate + H2O = 1L-''myo''-inositol 1,2,3,4,6-pentakisphosphate + phosphate
''myo''-Inositol hexakisphosphate is also known as phytic acid.
These enzymes belon ...
*
Protein tyrosine phosphatase
Protein tyrosine phosphatases (EC 3.1.3.48, systematic name protein-tyrosine-phosphate phosphohydrolase) are a group of enzymes that remove phosphate groups from phosphorylated tyrosine residues on proteins:
: proteintyrosine phosphate + H2O = ...
References
EC 3.1.3
Enzymes of unknown structure
{{3.1-enzyme-stub