Beyond rational—biosensor-guided isolation of 100 independently evolved bacterial strain variants and comparative analysis of their genomes

Table 3 Key Performance Indicators of selected C. glutamicum CgHis2 variants obtained from lab-scale bioreactor cultivations in batch mode. Maximum titers and yields were derived directly from measurements and specific rates via process modeling. For the latter, asymmetric confidence bounds were estimated by following a parametric bootstrapping approach (values in brackets)

Strain	CgHis2 reference	CgHis2 variant 12–10-5–6	CgHis2 ΔfasB Δpyk1 NCgl2981-D735G pks-D1186N
OD₆₀₀ [-]	30.4	30.6	41.5
CDW [g L⁻¹]	8.3	8.8	11.3
l-histidine titer [mM]	14.8	28.6	29.1
Volumetric productivity [g L⁻¹ h⁻¹]	0.03	0.05	0.05
l-histidine yield [C-mol C-mol⁻¹]	0.07	0.13	0.13
Growth rate [h⁻¹]	0.15 [0.148, 0.160]	0.06 [0.054, 0.058]	0.05 [0.048, 0.052]
d-glucose uptake rate [mmol g_CDW h⁻¹]	1.96 [1.768, 2.139]	1.28 [1.167, 1.383]	1.07 [0.995, 1.137]
l-histidine production rate [mmol g_CDW h⁻¹]	0.13 [0.122, 0.142]	0.14 [0.131, 0.154]	0.17 [0.157, 0.188]

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