Transferase
Encyclopedia
In biochemistry
, a transferase is an enzyme
that catalyzes the transfer of a functional group
(e.g., a methyl or phosphate
group) from one molecule
(called the donor) to another (called the acceptor). 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. The donor is often a coenzyme.
is a transferase that catalyzes the transfer of a methyl group to a DNA
acceptor.
classification. Transferases can be further classified into nine subclasses:
Biochemistry
Biochemistry, sometimes called biological chemistry, is the study of chemical processes in living organisms, including, but not limited to, living matter. Biochemistry governs all living organisms and living processes...
, a transferase 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 the transfer of a functional group
Functional group
In organic chemistry, functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. The same functional group will undergo the same or similar chemical reaction regardless of the size of the molecule it is a part of...
(e.g., a methyl or 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...
group) from one molecule
Molecule
A molecule is an electrically neutral group of at least two atoms held together by covalent chemical bonds. Molecules are distinguished from ions by their electrical charge...
(called the donor) to another (called the acceptor). For example, an enzyme that catalyzed this reaction would be a transferase:
- A–X + B → A + B–X
In this example, A would be the donor, and B would be the acceptor. The donor is often a coenzyme.
Nomenclature
Proper names of transferases are formed as "donor:acceptor grouptransferase." However, other names are much more common. The common names of transferases are often formed as "acceptor grouptransferase" or "donor grouptransferase." For example, a DNA methyltransferaseDNA methyltransferase
In biochemistry, the DNA methyltransferase family of enzymescatalyze the transfer of a methyl group to DNA. DNA methylation serves a wide variety of biological functions...
is a transferase that catalyzes the transfer of a methyl group to a DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
acceptor.
Classification
Transferases are classified as EC 2 in the EC numberEC number
The Enzyme Commission number is a numerical classification scheme for enzymes, based on the chemical reactions they catalyze....
classification. Transferases can be further classified into nine subclasses:
- EC 2.1 includes enzymes that transfer one-carbon groups (methyltransferaseMethyltransferaseA methyltransferase is a type of transferase enzyme that transfers a methyl group from a donor to an acceptor.Methylation often occurs on nucleic bases in DNA or amino acids in protein structures...
) - EC 2.2 includes enzymes that transfer aldehydeAldehydeAn aldehyde is an organic compound containing a formyl group. This functional group, with the structure R-CHO, consists of a carbonyl center bonded to hydrogen and an R group....
or ketoneKetoneIn organic chemistry, a ketone is an organic compound with the structure RCR', where R and R' can be a variety of atoms and groups of atoms. It features a carbonyl group bonded to two other carbon atoms. Many ketones are known and many are of great importance in industry and in biology...
groups - EC 2.3 includes acyltransferaseAcyltransferaseAcyltransferase is a type of transferase enzyme that acts upon acyl groups.Examples include:* Glyceronephosphate O-acyltransferase* Lecithin-cholesterol acyltransferase...
s - EC 2.4 includes glycosyltransferaseGlycosyltransferaseGlycosyltransferases are enzymes that act as a catalyst for the transfer of a monosaccharide unit from an activated nucleotide sugar to a glycosyl acceptor molecule, usually an alcohol....
s - EC 2.5 includes enzymes that transfer alkyl or arylArylIn the context of organic molecules, aryl refers to any functional group or substituent derived from an aromatic ring, be it phenyl, naphthyl, thienyl, indolyl, etc....
groups, other than methyl groups - EC 2.6 includes enzymes that transfer nitrogenous groups (transaminaseTransaminaseIn biochemistry, a transaminase or an aminotransferase is an enzyme that catalyzes a type of reaction between an amino acid and an α-keto acid. To be specific, this reaction involves removing the amino group from the amino acid, leaving behind an α-keto acid, and transferring it to the...
) - EC 2.7 includes enzymes that transfer phosphorusPhosphorusPhosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...
-containing groups (phosphotransferasePhosphotransferasePhosphotransferases are a category of enzymes that catalyze phosphorylation reactions. The general form of the reactions they catalyze is: A—P + B ⇔ B—P + A...
, including polymerasePolymeraseA polymerase is an enzyme whose central function is associated with polymers of nucleic acids such as RNA and DNA.The primary function of a polymerase is the polymerization of new DNA or RNA against an existing DNA or RNA template in the processes of replication and transcription...
and kinaseKinaseIn chemistry and biochemistry, a kinase is a type of enzyme that transfers phosphate groups from high-energy donor molecules, such as ATP, to specific substrates, a process referred to as phosphorylation. Kinases are part of the larger family of phosphotransferases...
) - EC 2.8 includes enzymes that transfer sulfurSulfurSulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
-containing groups (sulfurtransferaseSulfurtransferaseA sulfurtransferase is a transferase enzyme that act upon atoms of sulfur.An example is thiosulfate sulfurtransferase....
and sulfotransferaseSulfotransferaseSulfotransferases are transferase enzymes that catalyze the transfer of a sulfate group from a donor molecule to an acceptor alcohol or amine. The most common sulfate donor is 3'-phosphoadenosine-5'-phosphosulfate...
) - EC 2.9 includes enzymes that transfer seleniumSeleniumSelenium is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium...
-containing groups