Metabolic engineering of Bacillus subtilis for redistributing the carbon flux to 2,3-butanediol by manipulating NADH levels

Table 1 The glucose metabolic flux distribution in different B. subtilis strains (unit: mol/mol glucose)

Strain	2,3-BD	Acetoin	Lactate	Ethanol	Acetate	Biomass^a
ACR	0.702 ± 0.021	0.178 ± 0.005	0.036 ± 0.001	0.015 ± 0.001	0.032 ± 0.001	0.042 ± 0.002
AY	0.764 ± 0.022	0.136 ± 0.004	0.042 ± 0.002	0.016 ± 0.001	0.026 ± 0.001	0.042 ± 0.002
AFY	0.832 ± 0.024	0.061 ± 0.003	0.053 ± 0.002	0.018 ± 0.001	0.023 ± 0.001	0.041 ± 0.002
AFYL	0.881 ± 0.025	0.042 ± 0.002	0.007 ± 0.000	0.021 ± 0.001	0.029 ± 0.001	0.046 ± 0.002

All assays were performed by triplicate cultures; standard deviations of the biological replicates were represented by error bars
ACR, B. subtilis 168 with pMA5-acr; AY, ACR blocked in YodC by insertion of a Cat expression cassette; AFY, Acr blocked in YodC by insertion of fdh gene; AFYL, AFY blocked in LdhA by insertion of a Cat expression cassette
^aAssuming the biomass formula is C_3.93H_7.07O_1.96N_0.79 with 3.35 % ash [34]

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