In biochemistry, a ligase (from the Latin verb ligāre — "to bind" or "to glue together") is an enzyme that can catalyse the joining of two molecules by forming a new chemical bond, with accompanying hydrolysis of adenosine triphosphate or other similar molecules. An example of such an enzyme that catalyzed this reaction would be a ligase: Biochemistry is the study of the chemistry of life, a bridge between biology and chemistry that studies how complex chemical reactions give rise to life. ... Latin was the language originally spoken in the region around Rome called Latium. ... Ribbon diagram of the catalytically perfect enzyme TIM. An enzyme is a protein that catalyzes, or speeds up, a chemical reaction. ... A chemical bond is the physical phenomenon of chemical substances being held together by attraction of atoms to each other through sharing, as well as exchanging, of electrons -or electrostatic forces. ... Hydrolysis is a chemical process in which a molecule is split into two parts by the addition of a molecule of water. ... Adenosine 5-triphosphate (ATP) is the nucleotide known in biochemistry as the molecular currency of intracellular energy transfer; that is, ATP is able to store and transport chemical energy within cells. ... Ribbon diagram of the catalytically perfect enzyme TIM. An enzyme is a protein that catalyzes, or speeds up, a chemical reaction. ... A catalyst (Greek: καταλύτης, catalytÄ“s) is a substance that accelerates the rate (speed) of a chemical reaction (see also catalysis). ...

A + B → A–B

Nomenclature

The common names of ligases often include the word "ligase", such as DNA ligase, an enzyme commonly used in molecular biology laboratories to join together DNA fragments. Other common names ligases include "synthetase", because they are used to synthesize new molecules, or "carboxylase" when they are used to add carbon dioxide to a molecule. In molecular biology, DNA ligase is a particular type of ligase (EC 6. ... Molecular biology is the study of biology at a molecular level. ... Biochemistry laboratory at the University of Cologne. ... The general structure of a section of DNA Deoxyribonucleic acid (DNA) is a nucleic acid —usually in the form of a double helix— that contains the genetic instructions specifying the biological development of all cellular forms of life (and most viruses). ... Synthesis (from the Greek words syn = plus and thesis = position) is commonly understood to be an integration of two or more pre-existing elements which results in a new creation. ... Carbon dioxide is an atmospheric gas comprised of one carbon and two oxygen atoms. ...

Note that "synthetase" should not be confused with synthases, as synthases do not use adenosine triphosphate and belong to the lyase group, while synthetases do use adenosine triphosphate. In biochemistry, a synthase is an enzyme which catalyzes a synthesis process. ... In biochemistry, a lyase is an enzyme that breaks various chemical bonds by means other than hydrolysis and oxidation, often forming a new double bond or a new ring structure. ...

Classification

Ligases are classified as EC 6 in the EC number classification of enzymes. Ligases can be further classified into six subclasses: EC numbers (Enzyme Commission numbers) are a numerical classification scheme for enzymes, based on the chemical reactions they catalyze. ...

• EC 6.1 includes ligases used to form carbon-oxygen bonds
• EC 6.2 includes ligases used to form carbon-sulfur bonds
• EC 6.3 includes ligases used to form carbon-nitrogen bonds
• EC 6.4 includes ligases used to form carbon-carbon bonds
• EC 6.5 includes ligases used to form phosphoric ester bonds
• EC 6.6 includes ligases used to form nitrogen-metal bonds

In organic chemistry and biochemistry esters are substances that have the functional group (R-COO-R) (the carbon is double-bonded to one oxygen atom and single-bonded to another) and consist of an alkane united with the residue of any oxygen acid, organic or inorganic. ...

See also

• Hydrolase
• Isomerase
• Lyase
• Oxidoreductase
• Transferase

In biochemistry, a hydrolase is an enzyme that can break a chemical bond by hydrolysis. ... In biochemistry, an isomerase is any enzyme that catalyses the interconversion of isomers. ... In biochemistry, a lyase is an enzyme that breaks various chemical bonds by means other than hydrolysis and oxidation, often forming a new double bond or a new ring structure. ... In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule (the oxidant, also called the hydrogen donor or electron donor) to another (the reductant, also called the hydrogen acceptor or electron acceptor). ... In biochemistry, a transferase is an enzyme that catalyzes the transfer of a functional group (e. ...

References

• EC 6 Introduction from the Department of Chemistry at Queen Mary University of London