:Capsanthin/capsorubin synthase

{{Infobox enzyme

| Name = Capsanthin/capsorubin synthase

| EC_number = 5.3.99.8

| CAS_number = 162032-85-1

| GO_code =

| image =

| width =

| caption =

}}

Capsanthin/capsorubin synthase ({{EnzExplorer|5.3.99.8}}, CCS, ketoxanthophyll synthase, capsanthin-capsorubin synthase) is an enzyme with systematic name violaxanthin—capsorubin isomerase (ketone-forming).{{cite journal | vauthors = Bouvier F, Hugueney P, d'Harlingue A, Kuntz M, Camara B | title = Xanthophyll biosynthesis in chromoplasts: isolation and molecular cloning of an enzyme catalyzing the conversion of 5,6-epoxycarotenoid into ketocarotenoid | journal = Plant J. | volume = 6 | pages = 45–54 | date = 1994 | pmid = 7920703 | doi = 10.1046/j.1365-313x.1994.6010045.x | doi-access = free }}{{cite journal | vauthors = Lefebvre V, Kuntz M, Camara B, Palloix A | title = The capsanthin-capsorubin synthase gene: a candidate gene for the y locus controlling the red fruit colour in pepper | journal = Plant Mol. Biol. | volume = 36 | pages = 785–789 | date = 1998 | pmid = 9526511 | doi = 10.1023/A:1005966313415}}{{cite journal | vauthors = Xu CJ, Chen DM, Zhang SL | title = [Molecular cloning of full length capsanthin/capsorubin synthase homologous gene from orange (Citrus sinensis)] | journal = Shi Yan Sheng Wu Xue Bao | volume = 34 | pages = 147–150 | date = 2001 | pmid = 12549109 }} This enzyme catalyses the following chemical reaction

: (1) violaxanthin $\backslash rightleftharpoons$ capsorubin

: (2) antheraxanthin $\backslash rightleftharpoons$ capsanthin

This multifunctional enzyme is induced during chromoplast differentiation in plants.