In enzymology, an RNA ligase (ATP) () 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 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 ...

:ATP + (ribonucleotide)n + (ribonucleotide)m

\rightleftharpoons

AMP + diphosphate + (ribonucleotide)n⁺m The 3 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 ...

, (ribonucleotide)n, and (ribonucleotide)m, whereas its 3 products are AMP,

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 (ribonucleotide)n+m. This enzyme belongs to the family of

ligase In biochemistry, a ligase is an enzyme that can catalyze the joining ( ligation) of two large molecules by forming a new chemical bond. This is typically via hydrolysis of a small pendant chemical group on one of the larger molecules or the enz ...

s, specifically those forming phosphoric-ester bonds. 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 poly(ribonucleotide):poly(ribonucleotide) ligase (AMP-forming). Other names in common use include polyribonucleotide synthase (ATP), RNA ligase, polyribonucleotide ligase, and ribonucleic ligase.

Structural studies

As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes and .

References

* EC 6.5.1 Enzymes of known structure {{ligase-stub