Unraveling complex molecular transformations of N-β-alanyldopamine that account for brown coloration of insect cuticle.

LC/MS analysis of the reaction mixture of NBAD-cuticular enzyme reactions reveals the novel production of colored quinone adducts that are not possible for NADA. Therefore, our results suggest that the brown coloration of cuticle formed through NBAD crosslinking is likely due to the formation and accumulation of NBAD quinone and its adducts, while NADA quinone adducts tend not to form during NADA crosslinking, producing a nearly colorless cuticle.