Engineered Bacillus subtilis 168 produces L-malate by heterologous biosynthesis pathway construction and lactate dehydrogenase deletion.
In the present work, Bacillus subtilis was engineered to produce L-malate. Initially, the study revealed that the slight fumarase activity under anaerobic conditions is extremely favourable for L-malate one-step fermentation accumulation. Subsequently, an efficient heterologous biosynthesis pathway formed by Escherichia coli phosphoenolpyruvate carboxylase and Saccharomyces cerevisiae malate dehydrogenase was introduced into B. subtilis, which led to 6.04 ± 0.19 mM L-malate production. Finally, the L-malate production was increased 1.5-fold to 9.18 ± 0.22 mM by the deletion of lactate dehydrogenase. Under two-stage fermentation conditions, the engineered B. subtilis produced up to 15.65 ± 0.13 mM L-malate, which was 86.3 % higher than that under anaerobic fermentation conditions. Though the L-malate production by the recombinant was low, this is the first attempt to produce L-malate in engineered B. subtilis and paves the way for further improving L-malate production in B. subtilis.
Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
Li
L
Mu
Jianping
J
Wen
D001412:Bacillus subtilis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D053898:Biosynthetic Pathways; D005285:Fermentation; D005649:Fumarate Hydratase / Q000378:metabolism; D005818:Genetic Engineering / Q000379:methods; D007770:L-Lactate Dehydrogenase / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism*; D008293:Malates / Q000378:metabolism*
D008293:Malates; C030298:malic acid; D007770:L-Lactate Dehydrogenase; D005649:Fumarate Hydratase