Download MendeleyAn Esterase-like Lyase Catalyzes Acetate Elimination in Spirotetronate/Spirotetramate Biosynthesis.
Lees, N.R., Han, L.C., Byrne, M.J., Davies, J.A., Parnell, A.E., Moreland, P.E.J., Stach, J.E.M., van der Kamp, M.W., Willis, C.L., Race, P.R.(2019) Angew Chem Int Ed Engl 58: 2305-2309
- PubMed: 30664319
- DOI: https://doi.org/10.1002/anie.201812105
- Primary Citation of Related Structures:
4YWF, 5NO5 - PubMed Abstract:
Spirotetronate and spirotetramate natural products include a multitude of compounds with potent antimicrobial and antitumor activities. Their biosynthesis incorporates many unusual biocatalytic steps, including regio- and stereo-specific modifications, cyclizations promoted by Diels-Alderases, and acetylation-elimination reactions. Here we focus on the acetate elimination catalyzed by AbyA5, implicated in the formation of the key Diels-Alder substrate to give the spirocyclic system of the antibiotic abyssomicin C. Using synthetic substrate analogues, it is shown that AbyA5 catalyzes stereospecific acetate elimination, establishing the (R)-tetronate acetate as a biosynthetic intermediate. The X-ray crystal structure of AbyA5, the first of an acetate-eliminating enzyme, reveals a deviant acetyl esterase fold. Molecular dynamics simulations and enzyme assays show the use of a His-Ser dyad to catalyze either elimination or hydrolysis, via disparate mechanisms, under substrate control.
Organizational Affiliation:
School of Chemistry, University of Bristol, Bristol, BS8 1TS, UK.
