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Bioprocesses conducted under conditions with restricted O2 supply are increasingly exploited for the synthesis of reduced biochemicalsusing different biocatalysts. The model facultative anaerobe Escherichia coli has elaborate sensing and signal transductionmechanisms for redox control in response to the availability of O2 and other electron acceptors. The ArcBA two-componentsystem consists of ArcB, a membrane-associated sensor kinase, and ArcA, the cognate response regulator. The tripartitehybrid kinase ArcB possesses a transmembrane, a PAS, a primary transmitter (H1), a receiver (D1), and a phosphotransfer (H2)domain. Metabolic fluxes were compared under anoxic conditions in a wild-type E. coli strain, its arcB derivative, and two partialarcB deletion mutants in which ArcB lacked either the H1 domain or the PAS-H1-D1 domains. These analyses revealed thatelimination of different segments in ArcB determines a distinctive distribution of D-glucose catabolic fluxes, different from thatobserved in the arcB background. Metabolite profiles, enzyme activity levels, and gene expression patterns were also investigatedin these strains. Relevant alterations were observed at the P-enol-pyruvate/pyruvate and acetyl coenzyme A metabolicnodes, and the formation of reduced fermentation metabolites, such as succinate, D-lactate, and ethanol, was favored in the mutantstrains to different extents compared to the wild-type strain. These phenotypic traits were associated with altered levels ofthe enzymatic activities operating at these nodes, as well as with elevated NADH/NAD ratios. Thus, targeted modification ofglobal regulators to obtain different metabolic flux distributions under anoxic conditions is emerging as an attractive tool formetabolic engineering purposes.