Beta-Carotene Oxygenase 2 (bCO2)

BCDO2 catalyzes the asymmetric oxidative cleavage of beta-carotene in carotene metabolism.The deduced 556-amino acid human BCDO2 protein shares 72% amino acid identity with its mouse homolog. RT-PCR analysis of mouse tissues detected Bcdo2 expression in small intestine, liver, kidney, and testis, as well as spleen, brain, lung, and heart.

Northern blot analysis of a multiple tissue mRNA detected a 2.2-kb human BCDO2 transcript in heart and liver and a 2.4-kb transcript in kidney.Bcdo2 catalyzed the asymmetric cleavage of beta-carotene at the 9-prime, 10-prime carbon double bond to form beta-apo-10-prime-carotenal and beta-ionone. Further analyses demonstrated that Bcdo2 also catalyzed the oxidative cleavage of lycopene.