O-methyltransferases selectively modify anthraquinone natural products

In this issue of Structure, Huber et al. identify five O-methyltransferases, and three of them catalyze the sequential methylation of the Gram-negative bacterium-derived aromatic polyketide anthraquinone AQ-256. They present co-crystal structures with bound AQ-256 and its methylated derivatives, which explains the specificities of these O-methyltransferases. In this issue of Structure, Huber et al. identify five O-methyltransferases, and three of them catalyze the sequential methylation of the Gram-negative bacterium-derived aromatic polyketide anthraquinone AQ-256. They present co-crystal structures with bound AQ-256 and its methylated derivatives, which explains the specificities of these O-methyltransferases. A set of closely related methyltransferases for site-specific tailoring of anthraquinone pigmentsHuber et al.StructureMarch 23, 2023In BriefAnthraquinones can carry methyl groups, but the corresponding tailoring enzymes have remained elusive. Huber et al. identified a tandem array of five methyltransferase genes, of which three are required for anthraquinone modification. Activity assays and X-ray structures of all five enzymes reveal substrate specificities and illustrate the methylation sequence. Full-Text PDF