Table 5.

Competition assays to measure the effects of sgrS mutations on growth with αMG in minimal MOPS medium with glycerol

E. coli strain A genotype	E. coli strain B genotype	Without αMG		With 0.5% αMG
		CIa	P valueb	CI	P value
λattB::tet	WT	0.94 ± 0.04	NS	1.04 ± 0.06	NS
ΔsgrS λattB::tet	WT	0.98 ± 0.1	NS	0.38 ± 0.11	<0.0001
sgrS1manXYZ λattB::tet	WT	1.03 ± 0.12	NS	0.42 ± 0.06	0.014
sgrS28ptsG λattB::tet	WT	0.96 ± 0.3	NS	0.34 ± 0.02	0.022
sgrS26ptsG,yigL λattB::tet	WT	0.92 ± 0.07	NS	0.5 ± 0.03	0.015
sgrS1manXYZ λattB::tet	ΔsgrS	0.96 ± 0.13	NS	1.01 ± 0.19	NS
sgrS26ptsG,yigL λattB::tet	ΔsgrS	1.1 ± 0.51	NS	1.86 ± 0.64	0.023
sgrS28ptsG λattB::tet	ΔsgrS	0.93 ± 0.21	NS	1.11 ± 0.16	NS
sgrS26ptsG,yigL λattB::tet	sgrS1manXYZ	1.03 ± 0.06	NS	1.75 ± 0.13	0.019
sgrS28ptsG λattB::tet	sgrS1manXYZ	0.91 ± 0.12	NS	1.02 ± 0.1	NS
sgrS26ptsG,yigL λattB::tet	sgrS28ptsG	1.03 ± 0.11	NS	2.09 ± 0.25	0.02

^aSee Materials and Methods for detailed procedures. The competition index (CI) is calculated as follows: (log₁₀ strain A output/log₁₀ strain B output)/(log₁₀ strain A input/log₁₀ strain B input). The data presented are the averages ± standard deviations of three independent experiments.

^bStudent's t test was used to compare the output and inoculum. NS, not significant (P ≥ 0.05).