Phosphopentomutase
Encyclopedia
In enzymology, a phosphopentomutase is an enzyme
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...


alpha-D-ribose 1-phosphate D-ribose 5-phosphate


Hence, this enzyme has one substrate
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...

, alpha-D-ribose 1-phosphate, and one product
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...

, D-ribose 5-phosphate.

This enzyme belongs to the family of isomerase
Isomerase
In biochemistry, an isomerase is an enzyme that catalyzes the structural rearrangement of isomers. Isomerases thus catalyze reactions of the formwhere B is an isomer of A.-Nomenclature:...

s, specifically the phosphotransferases (phosphomutases), which transfer phosphate groups within a molecule. The systematic name of this enzyme class is alpha-D-ribose 1,5-phosphomutase. Other names in common use include phosphodeoxyribomutase, deoxyribose phosphomutase, deoxyribomutase, phosphoribomutase, alpha-D-glucose-1,6-bisphosphate:deoxy-D-ribose-1-phosphate, phosphotransferase, and D-ribose 1,5-phosphomutase. This enzyme participates in pentose phosphate pathway
Pentose phosphate pathway
The pentose phosphate pathway is a process that generates NADPH and pentoses . There are two distinct phases in the pathway. The first is the oxidative phase, in which NADPH is generated, and the second is the non-oxidative synthesis of 5-carbon sugars...

 and purine metabolism
Purine metabolism
-Biosynthesis:Purines are biologically synthesized as nucleotides and in particular as ribotides, i.e. bases attached to ribose 5-phosphate. A key regulatory step is the production of 5-phospho-α-D-ribosyl 1-pyrophosphate by PRPP synthetase, which is activated by inorganic phosphate and...

. It has 3 cofactors
Cofactor (biochemistry)
A cofactor is a non-protein chemical compound that is bound to a protein and is required for the protein's biological activity. These proteins are commonly enzymes, and cofactors can be considered "helper molecules" that assist in biochemical transformations....

: D-ribose 1,5-bisphosphate, alpha-D-Glucose 1,6-bisphosphate, and 2-Deoxy-D-ribose 1,5-bisphosphate.

Structural studies

The first published description of a structure
Tertiary 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:...

 of a prokaryotic phosphopentomutase was in 2011. Structures of Bacillus cereus phosphopentomutase as it was purified, after activation, bound to ribose 5-phosphate and bound to glucose 1,6-bisphosphate are deposited in 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....

with accession codes , , and , respectively.
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