Enhancing butanol tolerance of Escherichia coli reveals hydrophobic interaction of multi-tasking chaperone SecB

Table 2 Tolerance of E. coli harboring SecB and SecB_T10A toward diverse solvents

Solvent^a	logP	E. coli JM109/pQE80L			E. coli JM109/pQE80L-secB			E. coli JM109/pQE80L-secB_T10A
Solvent^a	logP	μ^b/h⁻¹	T^c/%	A^d/%	μ/h⁻¹	T/%	A/%	μ/h⁻¹	T/%	A/%
PBS	–	–	–	14 ± 1	–	–	15 ± 1	–	–	16 ± 1
DMF	− 1.0	0.294 ± 0.015	42.4 ± 1.9	17 ± 1	0.462 ± 0.015	56.6 ± 1.1	17 ± 5	0.520 ± 0.014	65.0 ± 1.7	17 ± 3
Acetonitrile	− 0.33	0.372 ± 0.014	35.4 ± 0.9	18 ± 2	0.511 ± 0.022	76.3 ± 1.7	18 ± 1	0.430 ± 0.012	76.9 ± 2.5	18 ± 2
Ethanol	− 0.24	0.418 ± 0.011	51.1 ± 0.3	21 ± 8	0.420 ± 0.012	60.6 ± 1.0	23 ± 2	0.408 ± 0.013	64.3 ± 0.4	23 ± 1
Acetone	− 0.23	0.100 ± 0.004	11.9 ± 0.4	16 ± 1	0.183 ± 0.013	14.3 ± 0.1	18 ± 6	0.114 ± 0.009	12.6 ± 0.7	18 ± 11
i-Propanol	0.39	0.121 ± 0.006	14.2 ± 0.4	23 ± 1	0.244 ± 0.012	20.0 ± 0.2	24 ± 3	0.251 ± 0.012	24.9 ± 0.2	26 ± 7
i-Butanol	0.76	0.083 ± 0.008	7.27 ± 0.28	13 ± 1	0.223 ± 0.011	13.1 ± 0.1	13 ± 5	0.235 ± 0.012	14.7 ± 0.2	12 ± 1
n-Butanol	0.88	0.019 ± 0.005	2.86 ± 0.40	14 ± 1	0.136 ± 0.016	9.13 ± 0.21	13 ± 1	0.169 ± 0.013	14.4 ± 0.9	11 ± 1
Toluene	2.5	0.016 ± 0.004	1.19 ± 0.18	1.9 ± 0.6	0.046 ± 0.008	4.83 ± 0.21	1.4 ± 0.8	0.071 ± 0.006	6.12 ± 0.21	1.3 ± 0.9
Cyclohexane	3.2	0.026 ± 0.006	0.59 ± 0.21	4.8 ± 1.1	0.067 ± 0.007	3.11 ± 0.23	3.5 ± 0.8	0.038 ± 0.005	2.27 ± 0.29	2.6 ± 1.9

^aSolvent concentration: 3% N,N-dimethylformamide (DMF), 3% acetonitrile, 3% ethanol, 1% acetone, 3% i-propanol, 3% i-butanol, 1.2% n-butanol, 0.2% toluene and 0.8% cyclohexane
^bμ denotes specific growth rate between 0 and 2 h (Eq. 1)
^cT denotes tolerance to butanol (Eq. 2)
^dA denotes adhesion rate of solvents (Eq. 3). All experiments were performed in triplicate. Growth curves of all the tested strains are available in Additional file