Patent ID: 8877482

Claim:
A succinic acid-producing microbial variant lacking a lactate dehydrogenase gene (ldhA) and an acetate kinase gene (ackA) while maintaining a phosphotransacetylase gene (pta), which is capable of producing succinic acid at high concentration in anaerobic conditions, wherein the succinic acid-producing microbial variant is selected from the group consisting of Actinobacillus sp., Anaerobiospirillum sp., and Mannheimia sp. and wherein said succinic acid-producing microbial variant is Mannheimia succiniciproducens ALK, whose accession number is KCTC 12326BP wherein a lactate dehydrogenase gene (ldhA) and an acetate kinase gene (ackA) are disrupted in said variant.