Described herein is a novel three domain gene from Schizochytrium, denoted carotene synthase, that encodes a protein with three different enzymatic activities: phytoene dehydrogenase (PD), phytoene synthase (PS), and lycopene cyclase (LC). Also described is the isolated gene encoding the carotene synthase, homologues thereof, the enzyme encoded by such gene, biologically active portions and homologues thereof, recombinant nucleic acid molecules, microorganisms and plants that have been genetically modified to increase or decrease the action of such gene, and methods of producing carotenoids and derivatives thereof or methods of producing microorganisms and lipid products lacking pigmentation using the knowledge of the carotene synthase described herein.