Table 3 Phenotypic and functional effects of selected marC, acrAB, mdh, and rph mutations

marC

ΔmarC::kan (xylose media)

X1,X2,X3 (IS1/IS5 insertion)

-5.0 ± 0.5%

-2.4 ± 0.1%

39 ± 2%

7.6 ± 0.5%

-

ΔmarC::kan (glucose media)

G1,G3 (IS1 insertion)

-3.2 ± 0.2%

-7.8 ± 0.3%

20 ± 5%

40 ± 10%

-

acrAB

acrA 483735 +1:A

X3.5

14 ± 1%

3.3 ± 0.1%

49 ± 9%

72.4 ± 0.8%

Reduced EtBR efflux; 188 ± 7% increase in intracellular EtBr

ΔacrA::kan

N/A (control)

6.5 ± 0.6%

7.6 ± 0.5%

32 ± 5%

103 ± 1%

Reduced EtBR efflux; 210 ± 10% increase in intracellular EtBr

acrB 480665 G→A

G3.2

11.2 ± 0.9%

2.1 ± 0.1%

22 ± 3%

31 ± 1%

Reduced EtBR efflux; 21 ± 8% increase in intracellular EtBr

ΔacrB::kan

N/A (control)

5.7 ± 0.6%

-3.6 ± 0.1%

8.2 ± 1.1%

64 ± 2%

Reduced EtBR efflux; 340 ± 20% increase in intracellular EtBr

mdh

mdh 3390936 +5:AACCT

X3.5

-3.7 ± 0.3%

-1 ± 0.1%

0.4 ± 0.1%

13 ± 2%

Loss of function; no detectable mdh activity

mdh 3390726 -1:C

G3.2

2.3 ± 0.1%

4.4 ± 0.1%

-8.1 ± 3%

-1.2 ± 0.1%

Loss of function; no detectable mdh activity

Δmdh::kan

N/A (control)

-1.6 ± 0.2%

4 ± 0.1%

10.8 ± 1.6%

10 ± 1%

Loss of function; no detectable mdh activity

rph

rph 3823220 +4:GTCG

G3.2

39 ± 2%

11.9 ± 0.1%

49 ± 16%

-12.9 ± 0.1%

-