Figure 2.

High-resolution mass spectra of triketide lactones from in vitro reactions. Pik127 and Pik167 incubated with unlabeled methylmalonate (left) and ¹³C₄-labeled methylmalonate (right). The [M−H₂O+H]⁺, [M+H]⁺, and [M+Na]⁺ adducts were observed for each product.