<p>Chalcone isomerase (<db_xref db="EC" dbkey="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 <taxon tax_id="4102">Petunia hybrida</taxon> (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) [<cite idref="PUB00024704"/>].</p><p>This entry represents chalcone isomerases and enzymes with a common structure.</p> Chalcone isomerase