L-Malic acid (MA) is a commonly used chemical. The Gram-negative bacteriumMannheimia succiniciproducens has a strong anaplerotic pathway, suggesting that it hasgood potential for malic acid production. Thus, we aimed to create an efficient malic acidproduction strain, starting from a succinic acid producing M. succiniproducenspreviously developed in our lab. By deletion of the fumC gene encoding fumarase, theconversion of malic acid to fumarate was blocked, resulting in accumulation of malicacid as the main product. These results provide useful information for the rationalmetabolic engineering to improve MA production in strains with strong anapleroticpathways. [This work was supported by the Technology Development Program to SolveClimate Changes on Systems Metabolic Engineering for Biorefineries from the Ministryof Science, ICT and Future Planning (MSIP) through the National Research Foundation(NRF) of Korea . MG was additionallysupported by the Swedish research council Formas].