Authors: Won Seok Jung Eunji Kim Young Ji Yoo Yeon Hee Ban Eun Ji Kim Yeo Joon Yoon
Publish Date: 2014/01/12
Volume: 98, Issue: 8, Pages: 3701-3713
Abstract
Streptomyces venezuelae has an inherent advantage as a heterologous host for polyketide production due to its fast rate of growth that cannot be endowed easily through metabolic engineering However the utility of S venezuelae as a host has been limited thus far due to its inadequate intracellular reserves of the 2SethylmalonylCoA building block needed to support the biosynthesis of polyketides preventing the efficient production of the desired metabolite such as tylactone Here via precursor supply engineering we demonstrated that S venezuelae can be developed into a more efficient general heterologous host for the quick production of polyketides We first identified and functionally characterized the ethylmalonylCoA pathway which plays a major role in supplying the 2SethylmalonylCoA extender unit in S venezuelae Next S venezuelae was successfully engineered to increase the intracellular ethylmalonylCoA concentration by the deletion of the meaA gene encoding coenzyme B12dependent ethylmalonylCoA mutase in combination with ethylmalonate supplementation and was engineered to upregulate the expression of the heterologous tylosin PKS by overexpression of the pathway specific regulatory gene pikD Thus a dramatic increase ∼10fold in tylactone production was achieved In addition the detailed insights into the role of the ethylmalonylCoA pathway which is present in most streptomycetes provides a general strategy to increase the ethylmalonylCoA supply for polyketide biosynthesis in the most prolific family of polyketideproducing bacteriaWe thank Dr Kris Rathwell for critically reading this manuscript This work was supported by the Basic Science Research Program through the National Research Foundation of Korea NRF funded by the Ministry of Science ICT and Future Planning MISP 2013R1A2A1A01014230 the Intelligent Synthetic Biology Center of the Global Frontier Project funded by MISP 20110031961 and the KRRIB Research Initiative Program Republic of Korea
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