Application of a Pyruvate-Producing <i>Escherichia coli</i> Strain LAFCPCPt-accBC-aceE: A Case Study for <span style="font-variant: small-caps">d</span>-Lactate Production
Keisuke Wada,
Tatsuya Fujii,
Hiroyuki Inoue,
Hironaga Akita,
Tomotake Morita,
Akinori Matsushika
Affiliations
Keisuke Wada
Research Institute for Sustainable Chemistry (RISC), National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashi-hiroshima, Hiroshima 739-0046, Japan
Tatsuya Fujii
Research Institute for Sustainable Chemistry (RISC), National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashi-hiroshima, Hiroshima 739-0046, Japan
Hiroyuki Inoue
Research Institute for Sustainable Chemistry (RISC), National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashi-hiroshima, Hiroshima 739-0046, Japan
Hironaga Akita
Research Institute for Sustainable Chemistry (RISC), National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashi-hiroshima, Hiroshima 739-0046, Japan
Tomotake Morita
Research Institute for Sustainable Chemistry (RISC), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5-2, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
Akinori Matsushika
Research Institute for Sustainable Chemistry (RISC), National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashi-hiroshima, Hiroshima 739-0046, Japan
Pyruvate, a potential precursor of various chemicals, is one of the fundamental chemicals produced by the fermentation process. We previously reported a pyruvate-producing Escherichia coli strain LAFCPCPt-accBC-aceE (PYR) that has the potential to be applied to the industrial production of pyruvate. In this study, the availability of the PYR strain for the production of pyruvate-derivative chemicals was evaluated using a d-lactate-producing strain (LAC) based on the PYR strain. The LAC strain expresses a d-lactate dehydrogenase-encoding gene from Lactobacillus bulgaricus under the control of a T7 expression system. The d-lactate productivity of the LAC strain was further improved by limiting aeration and changing the induction period for the expression of d-lactate dehydrogenase-encoding gene expression. Under combined conditions, the LAC strain produced d-lactate at 21.7 ± 1.4 g·L−1, which was compatible with the pyruvate production by the PYR strain (26.1 ± 0.9 g·L−1). These results suggest that we have succeeded in the effective conversion of pyruvate to d-lactate in the LAC strain, demonstrating the wide versatility of the parental PYR strain as basal strain for various chemicals production.
