Sulfate adenylyltransferase
Encyclopedia
In enzymology, a sulfate adenylyltransferase 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 + sulfate diphosphate + adenylyl sulfate


Thus, the two 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...

 and sulfate
Sulfate
In inorganic chemistry, a sulfate is a salt of sulfuric acid.-Chemical properties:...

, whereas its two 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 diphosphate and adenylyl sulfate.

This enzyme 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, specifically those transferring phosphorus-containing nucleotide
Nucleotide
Nucleotides are molecules that, when joined together, make up the structural units of RNA and DNA. In addition, nucleotides participate in cellular signaling , and are incorporated into important cofactors of enzymatic reactions...

 groups (nucleotidyltransferase
Nucleotidyltransferase
Nucleotidyltransferases are transferase enzymes of phosphorus-containing groups, e.g., substituents of nucleotidylic acids or simply nucleoside monophosphates...

s). The systematic name of this enzyme class is ATP:sulfate adenylyltransferase. Other names in common use include ATP-sulfurylase, adenosine-5'-triphosphate sulfurylase, adenosinetriphosphate sulfurylase, adenylylsulfate pyrophosphorylase, ATP sulfurylase, ATP-sulfurylase, and sulfurylase. This enzyme participates in 3 metabolic pathways
Metabolism
Metabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories...

: 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...

, selenoamino acid metabolism, and sulfur metabolism
Sulfur metabolism
Sulfur metabolism is vital for all living organisms as it is a constituent of a number of essential organic molecules like cysteine, methionine, coenzyme A, and iron-sulfur clusters. These compounds are involved in a number of essential cellular processes such as protein biosynthesis or the...

.

Some sulphate adenylyltransferases are part of a bifunctional polypeptide chain
Polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...

 associated with adenosyl phosphosulphate (APS) kinase. Both 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...

s are required for PAPS (phosphoadenosine-phosphosulphate) synthesis from inorganic sulphate.

Structural studies

As of late 2007, 18 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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