Table 1. Strains and plasmids used in this study.
| Strain or plasmid | Relevant description | Source or reference |
| Escherichia coli | ||
| DH5α | F-,supE44 hsdR17 recA1 gyrA96 endA1 thi-1 relA1 deoR λ- | [25] |
| W3110 | F-, λ −, IN(rrnD-rrnE)1, rph-1 | KCTC |
| ATCC 9637 (W) | Wild -type | ATCC |
| JW3973 | F-, Δ(araD-araB)567, ΔlacZ4787(::rrnB-3), λ −,rph-1, ΔmetA780::kan, Δ(rhaD-rhaB)568, hsdR514 | Keio collection National Institute of Genetics, Japan |
| JW0195 | F-, Δ(araD-araB)567, ΔlacZ4787(::rrnB-3), λ −,rph-1, ΔmetN724::kan, Δ(rhaD-rhaB)568, hsdR514 | Keio collection National Institute of Genetics, Japan |
| WE | JW3973 carrying the wild-type metA gene | [27] |
| WE-LYD | WE carrying the metA gene with I124L, I229Y and N267D substitutions | [29] |
| W3110-LYD | W3110 carrying the metA gene with I124L, I229Y and N267D substitutions | This study |
| WE- PBADMetA | WE carrying the wild-type metA gene under PBAD promoter, kan | This study |
| WErph+ | WE carrying the rph gene from the strain E. coli ATCC 9637 | This study |
| WE-LYDrph+ | WE-LYD carrying the rph gene from the strain E. coli ATCC 9637 | This study |
| BL21(DE3) | F- ompT hsdSB(r-Bm-B) gal dcm(DE3) | Novagen (Billerica, USA) |
| Plasmids | ||
| pCP20 | ts rep,[cI857] (λ; ts), Apr, cat, [FLP] | [26] |
| pKD13 | oriR6γ, tL3LAM(Ter), Apr, rgnB(Ter), kan | [26] |
| pKD46 | λ Red (gam bet exo) ara C rep101(Ts), Apr | [26] |
| pUC18 | Cloning vector, Apr | Laboratory stock |
| pET22b/MetA | Expression vector contains the wild-type metA gene, Apr | [24] |
| pET22b/MetA-LYD | Expression vector contains the metA gene withI124L,I229Y and N267D substitutions, Apr | This study |
| pBAD/HisA | Expression vector, Apr | Invitrogen (Grand Island, USA |
Apr, ampicillin resistance; kan, kanamycin resistance gene.