A highly active Burkholderia polyketoacyl-CoA thiolase for production of triacetic acid lactone

Wang, Z.; Cheong, S.; Pereira, J. H.; Kim, J.; DeGiovanni, A.; Guo, Y.; Lan, G.; Barcelos, C. A.; Haushalter, R.; Lee, T. S.; Adams, P. D.; Keasling, J. D.

doi:10.1101/2022.12.04.519061

bioRxiv · 10.1101/2022.12.04.519061

A highly active Burkholderia polyketoacyl-CoA thiolase for production of triacetic acid lactone

Wang, Z.·Cheong, S.·Pereira, J. H.·Kim, J.·DeGiovanni, A.·Guo, Y.·Lan, G.·Barcelos, C. A.·Haushalter, R.·Lee, T. S.·Adams, P. D.·Keasling, J. D.

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Abstract

Triacetic acid lactone (TAL) is a platform chemical biosynthesized primarily through decarboxylative Claisen condensation by type III polyketide synthase 2-pyrone synthase (2-PS). However, this reaction suffers from intrinsic energy inefficiency and feedback inhibition by and competition for malonyl-CoA. TAL production through non-decarboxylative Claisen condensation by polyketoacyl-CoA thiolase alleviates many of these disadvantages. We discovered five more thiolases with TAL production activity by exploring homologs of a previously reported polyketoacyl-CoA thiolase, BktB, from Cupriavidus necator. Among them, the BktB homolog from Burkholderia sp. RF2-non_BP3 has [~] 30 times higher in vitro and in vivo TAL production activity and led to [~]10 times higher TAL titer than 2-PS when expressed in Escherichia coli, achieving a titer of 2.8 g/L in fed-batch fermentations. This discovery of a novel polyketoacyl-CoA thiolase with superior TAL production activity paves the way for realization of total biomanufacturing of TAL.

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Wang, Z., Cheong, S., Pereira, J. H., Kim, J., DeGiovanni, A., Guo, Y., Lan, G., Barcelos, C. A., Haushalter, R., Lee, T. S., Adams, P. D., Keasling, J. D.. 2022-12-05. A highly active Burkholderia polyketoacyl-CoA thiolase for production of triacetic acid lactone. https://doi.org/10.1101/2022.12.04.519061

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