Chalcone isomerase

Template:Short description Template:Infobox enzyme Template:Infobox protein family In enzymology, a chalcone isomerase (Template:EnzExplorer) is an enzyme that catalyzes the chemical reaction

a chalcone $\rightleftharpoons$ a flavanone

Hence, this enzyme has one substrate, a chalcone, and one product, a flavanone.

This enzyme belongs to the family of isomerases, specifically the class of intramolecular lyases. The systematic name of this enzyme class is flavanone lyase (decyclizing). This enzyme is also called chalcone-flavanone isomerase. This enzyme participates in flavonoid biosynthesis.

The Petunia hybrida (Petunia) genome contains two genes coding for very similar enzymes, ChiA and ChiB, but only the first seems to encode a functional chalcone isomerase.

Structural studies

As of late 2007, 7 structures have been solved for this class of enzymes, with PDB accession codes Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, and Template:PDB link.

Chalcone isomerase has a core 2-layer alpha/beta structure consisting of beta(3)-alpha(2)-beta-alpha(2)-beta(3).

Further reading

• Template:Cite journal

Template:Isomerase-stub