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

, a polynucleotide 5'-hydroxyl-kinase () is an

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

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 recyc ...

the

chemical reaction A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the pos ...

:ATP + 5'-dephospho-DNA

\rightleftharpoons

ADP + 5'-phospho-DNA Thus, the two substrates of this enzyme are

ATP ATP may refer to: Companies and organizations * Association of Tennis Professionals, men's professional tennis governing body * American Technical Publishers, employee-owned publishing company * ', a Danish pension * Armenia Tree Project, non ...

and 5'-dephospho-DNA, whereas its two products are

ADP Adp or ADP may refer to: Aviation * Aéroports de Paris, airport authority for the Parisian region in France * Aeropuertos del Perú, airport operator for airports in northern Peru * SLAF Anuradhapura, an airport in Sri Lanka * Ampara Air ...

and 5'-phospho-DNA. Polynucleotide kinase is a

T7 bacteriophage Bacteriophage T7 (or the T7 phage) is a bacteriophage, a virus that infects bacteria. It infects most strains of ''Escherichia coli'' and relies on these hosts to propagate. Bacteriophage T7 has a lytic life cycle, meaning that it destroys the ...

(or

T4 bacteriophage T4 or T-4 may refer to: Airports and airlines * Heathrow Terminal 4 * Tiyas Military Airbase, also known as the T-4 Airbase Biology and medicine * T4 phage, a bacteriophage * Thyroxine (T4), a form of thyroid hormone * the T4 spinal nerve * th ...

)

that catalyzes the transfer of a gamma-

phosphate In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid . The phosphate or orthophosphate ion is derived from phospho ...

from

to the free

hydroxyl In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...

end of the 5' DNA or

RNA Ribonucleic acid (RNA) is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and deoxyribonucleic acid ( DNA) are nucleic acids. Along with lipids, proteins, and carbohydra ...

. The resulting product could be used to end-label DNA or RNA, or in ligation reactions.

Nomenclature

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 di ...

s, specifically those transferring phosphorus-containing groups (

phosphotransferase Phosphotransferases are a category of enzymes ( EC number 2.7) that catalyze phosphorylation reactions. The general form of the reactions they catalyze is: :A-P + B \rightleftharpoons B-P + A Where ''P'' is a phosphate group and A and B are the do ...

s) with an alcohol group as an acceptor. The systematic name of this enzyme class is ATP:5'-dephosphopolynucleotide 5'-phosphotransferase. Other names in common use include: *ATP:5'-dephosphopolynucleotide 5'-phosphatase * PNK * polynucleotide 5'-hydroxyl kinase (phosphorylating), * 5'-hydroxyl polynucleotide kinase, * 5'-hydroxyl polyribonucleotide kinase, * 5'-hydroxyl RNA kinase, * DNA 5'-hydroxyl kinase, * DNA kinase, * polynucleotide kinase, and * polynucleotide 5'-hydroxy-kinase.

References

* *

External links

Vivo

New England Biolabs' T4 PNK page
EC 2.7.1 Enzymes of known structure {{2.7-enzyme-stub