In enzymology, a 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase () is an

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecule ...

that

catalyzes Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycl ...

the

chemical reaction A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and break ...

: : 2-C-methyl-D-erythritol 4-phosphate + CTP

\rightleftharpoons

diphosphate + 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol Image:MEP.png, 2-C-methylerythritol 4-phosphate Image:CTP chemical structure.png,

Cytidine triphosphate Cytidine triphosphate (CTP) is a pyrimidine nucleoside triphosphate. CTP, much like ATP, consists of a ribose sugar, and three phosphate groups. The major difference between the two molecules is the base used, which in CTP is cytosine. CTP is ...

Image:4-diphosphocytidyl-2-C-methylerythritol.png, 4-diphosphocytidyl-2-C-methylerythritol (CDP-ME) Thus, the two substrates of this enzyme are CTP and 2-C-methyl-D-erythritol 4-phosphate, whereas its two products are

diphosphate In chemistry, pyrophosphates are phosphorus oxyanions that contain two phosphorus atoms in a P–O–P linkage. A number of pyrophosphate salts exist, such as disodium pyrophosphate (Na2H2P2O7) and tetrasodium pyrophosphate (Na4P2O7), among o ...

and 4-diphosphocytidyl-2-C-methylerythritol. This enzyme belongs to the family of

transferase A transferase is any one of a class of enzymes that catalyse the transfer of specific functional groups (e.g. a methyl or glycosyl group) from one molecule (called the donor) to another (called the acceptor). They are involved in hundreds of ...

s, specifically those transferring phosphorus-containing

nucleotide Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecul ...

groups (

nucleotidyltransferase Nucleotidyltransferases are transferase enzymes of phosphorus-containing groups, e.g., substituents of nucleotidylic acids or simply nucleoside monophosphates. The general reaction of transferring a nucleoside monophosphate moiety from A to B, can ...

s). This enzyme participates in

isoprenoid The terpenoids, also known as isoprenoids, are a class of naturally occurring organic chemicals derived from the 5-carbon compound isoprene and its derivatives called terpenes, diterpenes, etc. While sometimes used interchangeably with "terpenes" ...

biosynthesis and stenvenosim. It

the third step of the

MEP pathway The non-mevalonate pathway—also appearing as the mevalonate-independent pathway and the 2-''C''-methyl-D-erythritol 4-phosphate/1-deoxy-D-xylulose 5-phosphate (MEP/DOXP) pathway—is an alternative metabolic pathway for the biosynthesis of the i ...

; the formation of CDP-ME (4-diphosphocytidyl-2C-methyl-D-erythritol) from CTP and MEP (2C-methyl-D-erythritol 4-phosphate). The isoprenoid pathway is a well known target for anti-infective drug development.

Nomenclature

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 semitrivial ...

of this enzyme class is CTP:2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase. This enzyme is also called: * MEP cytidylyltransferase * CDP-ME synthetase It is normally abbreviated IspD. It is also referenced by the open reading frame YgbP.

Structural studies

The crystal structure of the ''E. coli'' 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase , & , reported by Richard et al. (2001), was the first one for an enzyme involved in the MEP pathway. As of February 2010, 13 other

structures A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such a ...

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

Nomenclature

Structural studies

References

Further reading