Fig. 2.

HPLC analysis of AtCCD4 activity. (A) Incubation of the enzyme with all-trans-β-carotene yielded β-apo-10'-carotenal (P1). (B) Cleavage of zeaxanthin yielded 3-OH-β-apo-10'-carotenal (P2). (C) Incubation with β-apo-8'-carotenal led to a C₁₇ dialdehyde (P3) and traces of the corresponding C₁₇ dialcohol (†). (D) β-Apo-10'-carotenal yielded the C₁₄ dialcohol rosafluene (P4). UV/VIS spectra of the products are depicted in insets. The structures of the products are given. For structures of the substrates, see Supplementary Fig. 5. Analysis was performed using HPLC system 1.