Pyruvate, phosphate dikinase
Encyclopedia
In enzymology, a pyruvate, phosphate dikinase 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...


ATP + pyruvate + phosphate AMP + phosphoenolpyruvate + diphosphate


The 3 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 ATP
Adenosine triphosphate
Adenosine-5'-triphosphate is a multifunctional nucleoside triphosphate used in cells as a coenzyme. It is often called the "molecular unit of currency" of intracellular energy transfer. ATP transports chemical energy within cells for metabolism...

, pyruvate, and phosphate
Phosphate
A phosphate, an inorganic chemical, is a salt of phosphoric acid. In organic chemistry, a phosphate, or organophosphate, is an ester of phosphoric acid. Organic phosphates are important in biochemistry and biogeochemistry or ecology. Inorganic phosphates are mined to obtain phosphorus for use in...

, whereas its 3 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 AMP
Adenosine monophosphate
Adenosine monophosphate , also known as 5'-adenylic acid, is a nucleotide that is used as a monomer in RNA. It is an ester of phosphoric acid and the nucleoside adenosine. AMP consists of a phosphate group, the sugar ribose, and the nucleobase adenine...

, phosphoenolpyruvate
Phosphoenolpyruvate
Phosphoenolpyruvic acid , or phosphoenolpyruvate as the anion, is an important chemical compound in biochemistry. It has the high-energy phosphate bond found in living organisms, and is involved in glycolysis and gluconeogenesis...

 (PEP), and diphosphate. With that enzyme, bacteria can also form ATP if the reaction is running backwards.

This enzyme has been studied primarily in plants, but it has been studied in some bacteria as well. It is a key enzyme in gluconeogensis and photosynthesis that is responsible for reversing the reaction performed by pyruvate kinase in Embden-Meyerhof-Parnas glycolysis. It should not be confused with pyruvate, water dikinase
Pyruvate, water dikinase
In enzymology, a pyruvate, water dikinase is an enzyme that catalyzes the chemical reactionThe 3 substrates of this enzyme are ATP, pyruvate, and H2O, whereas its 3 products are AMP, phosphoenolpyruvate, and phosphate....

.

It belongs to the family of transferase
Transferase
In biochemistry, a transferase is an enzyme that catalyzes the transfer of a functional group from one molecule to another . For example, an enzyme that catalyzed this reaction would be a transferase:In this example, A would be the donor, and B would be the acceptor...

s, to be specific, those transferring phosphorus-containing groups (phosphotransferase
Phosphotransferase
Phosphotransferases are a category of enzymes that catalyze phosphorylation reactions. The general form of the reactions they catalyze is: A—P + B ⇔ B—P + A...

s) with paired acceptors (dikinase
Dikinase
Dikinases are a category of enzymes that catalyze the chemical reactionDikinases are all phosphotransferases. Their designated EC number is 2.7.9. It is one of the smallest groups of phosphotransferases....

s). The systematic name of this enzyme class is ATP:pyruvate, phosphate phosphotransferase. Other names in common use include pyruvate, orthophosphate dikinase, pyruvate-phosphate dikinase (phosphorylating), pyruvate, phosphate dikinase, pyruvate-inorganic phosphate dikinase, pyruvate-phosphate dikinase, pyruvate-phosphate ligase, pyruvic-phosphate dikinase, pyruvic-phosphate ligase, pyruvate, Pi dikinase, and PPDK. This enzyme participates in pyruvate metabolism and carbon fixation
Carbon fixation
In biology, carbon fixation is the reduction of carbon dioxide to organic compounds by living organisms. The obvious example is photosynthesis. Carbon fixation requires both a source of energy such as sunlight, and an electron donor such as water. All life depends on fixed carbon. Organisms that...

.

PPDK has been shown to undergo light/dark regulation by the pyruvate dikinase regulatory protein PDRP. PDRP reversibly phosphorylates Thr456 in the following reaction.
ADP AMP + phosphate

Structural studies

As of late 2007, 10 structures
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:...

 have been solved for this class of enzymes, with 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 codes , , , , , , , , , and .
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