Symmetrically cleaves beta-carotene into two molecules of retinal using a dioxygenase mechanism. all-trans-beta-carotene + O2 = 2 all-trans-retinal Binds 1 Fe(2+) ion per subunit. Cofactor metabolism; retinol metabolism. Expressed in liver, kidney, small intestine and testis. Abundantly expressed at embryonic day 7 with lower levels at embryonic days 11, 13 and 15. Belongs to the carotenoid oxygenase family.