Download MendeleyStructural and Biochemical Insight into the Recruitment of Acyl Carrier Protein-Linked Extender Units in Ansamitocin Biosynthesis.
Zhang, F., Ji, H., Ali, I., Deng, Z., Bai, L., Zheng, J.(2020) Chembiochem 21: 1309-1314
- PubMed: 31777147
- DOI: https://doi.org/10.1002/cbic.201900628
- Primary Citation of Related Structures:
6J0U, 6L3M, 6L3N - PubMed Abstract:
A few acyltransferase (AT) domains of modular polyketide synthases (PKSs) recruit acyl carrier protein (ACP)-linked extender units with unusual C2 substituents to confer functionalities that are not available in coenzyme A (CoA)-linked ones. In this study, an AT specific for methoxymalonyl (MOM)-ACP in the third module of the ansamitocin PKS was structurally and biochemically characterized. The AT uses a conserved tryptophan residue at the entrance of the substrate binding tunnel to discriminate between different carriers. A W275R mutation switches its carrier specificity from the ACP to the CoA molecule. The acyl-AT complex structures clearly show that the MOM-ACP accepted by the AT has the 2S instead of the opposite 2R stereochemistry that is predicted according to the biosynthetic derivation from a d-glycolytic intermediate. Together, these results reveal the structural basis of ATs recognizing ACP-linked extender units in polyketide biosynthesis.
Organizational Affiliation:
State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, 200240, Shanghai, P. R. China.
