InterPro domain: IPR016087

Chalcone isomerase ( 5.5.1.6 ; also known as chalcone-flavanone isomerase) is a plant enzyme responsible for the isomerisation of chalcone to naringenin, a key step in the biosynthesis of flavonoids. 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. Chalcone isomerase has a core 2-layer alpha/beta structure consisting of beta(3)-alpha(2)-beta-alpha(2)-beta(3) [ 1 ].

This entry represents chalcone isomerases and enzymes with a common structure.

1. Structure and mechanism of the evolutionarily unique plant enzyme chalcone isomerase. Nat. Struct. Biol. 7, 786-91