Structural and functional analysis of a lycopene β-monocyclase gene isolated from a unique marine bacterium that produces myxol

AbstractA gene coding for lycopene β-monocyclase, which metabolizes lycopene (ψ,ψ-carotene) to γ-carotene (β,ψ-carotene), was isolated for the first time from a unique marine bacterium strain P99-3 that produces myxol (a γ-carotene derivative). This lycopene β-monocyclase gene (designated crtYm) was included in the gene cluster which contained carotenoid biosynthetic gene (crtI, crtB, crtZ, crtY, and crtA) homologs. CrtYm, the CrtY homolog, metabolized lycopene to γ-carotene, which was confirmed by deletion/expression analysis of the crtYm and by subsequent analysis of the metabolites from lycopene based on the retention times on high-performance liquid chromatography, UV–visible absorption spectra, and mass spectrometry