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– Ligases have inconsistent naming conventions.
– Common names include ligase, synthetase, or synthase.
– Some ligases use the term carboxylase.
– Biochemical nomenclature sometimes distinguishes synthetases from synthases.
– The terms synthetase and synthase are often used interchangeably.

– Ligases are classified as EC 6 in the EC number classification.
– Subclasses include ligases forming carbon-oxygen, carbon-sulfur, and carbon-nitrogen bonds.
– Subclasses also cover ligases forming carbon-carbon and phosphoric ester bonds.
– Another subclass involves ligases forming nitrogen-metal bonds.
– Examples include acetyl-CoA carboxylase and DNA ligase.

Membrane-associated ligases:
– Some ligases associate with biological membranes.
– They can be peripheral membrane proteins.
– Certain ligases are anchored through a single transmembrane helix.
– Examples include ubiquitin ligase related proteins.

Etymology and pronunciation:
– The term ligase comes from Latin ligāre meaning to bind.
– The suffix -ase denotes an enzyme.
Ligase essentially means a binding enzyme.

See also:
– Chemistry portal.
– Related enzymes include DNA ligase and protease.
– Acetyl-CoA carboxylase is another ligase.
– Nuclease is also a relevant enzyme.

Ligase (Wikipedia)

In biochemistry, a ligase is an enzyme that can catalyze the joining (ligation) of two molecules by forming a new chemical bond. This is typically via hydrolysis of a small pendant chemical group on one of the molecules, typically resulting in the formation of new C-O, C-S, or C-N bonds. For example, DNA ligase can join two complementary fragments of nucleic acid by forming phosphodiester bonds, and repair single stranded breaks that arise in double stranded DNA during replication.

In general, a ligase catalyzes the following dehydration reaction, thus joining molecules A and B:

A-OH + B-H → A–B + H2O

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