Pyridoxal 5′-phosphate synthase (glutamine hydrolysing) (EC 4.3.3.6, ''PdxST'') is an
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...
with
systematic name D-ribose 5-phosphate,
D-glyceraldehyde 3-phosphate pyridoxal 5′-phosphate-lyase.
This enzyme
catalyses the following
chemical reaction
A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the pos ...
:
D-ribose 5-phosphate +
D-glyceraldehyde 3-phosphate +
L-glutamine
pyridoxal 5′-phosphate +
L-
glutamate
Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can syn ...
+ 3 H
2O + phosphate (overall reaction)
::(1a)
L-glutamine + H
2O
L-glutamate + NH
3
::(1b)
D-ribose 5-phosphate +
D-glyceraldehyde 3-phosphate + NH
3 pyridoxal 5′-phosphate + 4 H
2O +
phosphate
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 orthophosphoric acid .
The phosphate or orthophosphate ion is derived from phospho ...
The enzyme can also use
ribulose 5-phosphate and
dihydroxyacetone phosphate
Dihydroxyacetone phosphate (DHAP, also glycerone phosphate in older texts) is the anion with the formula HOCH2C(O)CH2OPO32-. This anion is involved in many metabolic pathways, including the Calvin cycle in plants and glycolysis.Nelson, D. L.; ...
.
References
External links
*
{{Portal bar, Biology, border=no
EC 4.3.3