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Abstract Converting renewable feedstocks to aromatic compounds using engineered microbes offers a robust approach for sustainable, environment‐friendly, and cost‐effective production of these value‐added products without the reliance on petroleum. In this study, rationally designedE. coli–E. colico‐culture systems were established for converting glycerol to 3‐hydroxybenzoic acid (3HB). Specifically, the 3HB pathway was modularized and accommodated by two metabolically engineeredE. colistrains. The co‐culture biosynthesis was optimized by using different cultivation temperatures, varying the inoculum ratio between the co‐culture strains, recruitment of a key pathway intermediate transporter, strengthening the critical pathway enzyme expression, and adjusting the timing for inducing pathway gene expression. Compared with theE. colimono‐culture, the optimized co‐culture showed 5.3‐fold improvement for 3HB biosynthesis. This study demonstrated the applicability of modular co‐culture engineering for addressing the challenges of aromatic compound biosynthesis.
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Engineering controllable alteration of malonyl-CoA levels to enhance polyketide production
Abstract Heterologous expression of polyketide synthase (PKS) genes inEscherichia colihas enabled the production of various valuable natural and synthetic products. However, the limited availability of malonyl-CoA (M-CoA) inE. coliremains a substantial impediment to high-titer polyketide production. Here we address this limitation by disrupting the native M-CoA biosynthetic pathway and introducing an orthogonal pathway comprising a malonate transporter and M-CoA ligase, enabling efficient M-CoA biosynthesis under malonate supplementation. This approach substantially increases M-CoA levels, enhancing fatty acid and polyketide titers while reducing the promiscuous activity of PKSs toward undesired acyl-CoA substrates. Subsequent adaptive laboratory evolution of these strains provides insights into M-CoA regulation and identifies mutations that further boost M-CoA and polyketide production. This strategy improvesE. colias a host for polyketide biosynthesis and advances understanding of M-CoA metabolism in microbial systems.
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- Award ID(s):
- 2036849
- PAR ID:
- 10599764
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Chemical Biology
- Volume:
- 21
- Issue:
- 8
- ISSN:
- 1552-4450
- Format(s):
- Medium: X Size: p. 1214-1225
- Size(s):
- p. 1214-1225
- Sponsoring Org:
- National Science Foundation
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