Structural highlights
Publication Abstract from PubMed
In type II polyketide synthases (PKSs), the ketosynthase-chain length factor (KS-CLF) complex catalyzes polyketide chain elongation with the acyl carrier protein (ACP). Highly reducing type II PKSs, represented by IgaPKS, produce polyene structures instead of the well-known aromatic skeletons. Here, we report the crystal structures of the Iga11-Iga12 (KS-CLF) heterodimer and the covalently cross-linked Iga10=Iga11-Iga12 (ACP=KS-CLF) tripartite complex. The latter structure revealed the molecular basis of the interaction between Iga10 and Iga11-Iga12, which differs from that between the ACP and KS of Escherichia coli fatty acid synthase. Furthermore, the reaction pocket structure and site-directed mutagenesis revealed that the negative charge of Asp 113 of Iga11 prevents further condensation using a beta-ketoacyl product as a substrate, which distinguishes IgaPKS from typical type II PKSs. This work will facilitate the future rational design of PKSs.
Structural basis for selectivity in a highly reducing type II polyketide synthase.,Du D, Katsuyama Y, Horiuchi M, Fushinobu S, Chen A, Davis TD, Burkart MD, Ohnishi Y Nat Chem Biol. 2020 May 4. pii: 10.1038/s41589-020-0530-0. doi:, 10.1038/s41589-020-0530-0. PMID:32367018[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Du D, Katsuyama Y, Horiuchi M, Fushinobu S, Chen A, Davis TD, Burkart MD, Ohnishi Y. Structural basis for selectivity in a highly reducing type II polyketide synthase. Nat Chem Biol. 2020 May 4. pii: 10.1038/s41589-020-0530-0. doi:, 10.1038/s41589-020-0530-0. PMID:32367018 doi:http://dx.doi.org/10.1038/s41589-020-0530-0