Biocatalytic Routes to Lactone Monomers for Polymer Production.
Messiha, H.L., Ahmed, S.T., Karuppiah, V., Suardiaz, R., Ascue Avalos, G.A., Fey, N., Yeates, S., Toogood, H.S., Mulholland, A.J., Scrutton, N.S.(2018) Biochemistry 57: 1997-2008
- PubMed: 29533655 
- DOI: https://doi.org/10.1021/acs.biochem.8b00169
- Primary Citation of Related Structures:  
6ER9, 6ERA - PubMed Abstract: 
Monoterpenoids offer potential as biocatalytically derived monomer feedstocks for high-performance renewable polymers. We describe a biocatalytic route to lactone monomers menthide and dihydrocarvide employing Baeyer-Villiger monooxygenases (BVMOs) from Pseudomonas sp. HI-70 (CPDMO) and Rhodococcus sp. Phi1 (CHMO Phi1 ) as an alternative to organic synthesis. The regioselectivity of dihydrocarvide isomer formation was controlled by site-directed mutagenesis of three key active site residues in CHMO Phi1 . A combination of crystal structure determination, molecular dynamics simulations, and mechanistic modeling using density functional theory on a range of models provides insight into the origins of the discrimination of the wild type and a variant CHMO Phi1 for producing different regioisomers of the lactone product. Ring-opening polymerizations of the resultant lactones using mild metal-organic catalysts demonstrate their utility in polymer production. This semisynthetic approach utilizing a biocatalytic step, non-petroleum feedstocks, and mild polymerization catalysts allows access to known and also to previously unreported and potentially novel lactone monomers and polymers.
Organizational Affiliation: 
Centre for Computational Chemistry, School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , U.K.