CGSC Strain#: 7978
Strain Designation: PA414      Source of Strain: Ahrweiler and Frieden
Sex: F- Chromosomal Markers: thr-1, ΔfolA207::kan, araC14, leuB6(Am), Δ(gpt-proA)62, lacY1, tsx-33, qsr'-0, glnX44(AS), galK2(Oc), λ^-, Rac-0, hisG4(Oc), rfbC1, mgl-51, rpoS396(Am), thyA760, rpsL31(strR), kdgK51, xylA5, mtl-1, argE3(Oc), thiE1
Strain Comments:

• ΔfolA207::kan-- Requires thyA^- background
• leuB6(Am)-- Suppressed by serU suppressor (supH)
• glnX44(AS)-- Mutation is a C to T transition at nucleotide 34 (3rd position of the anticodon)
• galK2(Oc)-- is a GAA(glu) to TAA(ochre) mutation, residue 134. Oller et al.1993. Apparently non-suppressible, since all revertants found were at the ochre site.
• thyA760-- Strains with this marker must have their medium supplemented with thymine (25ug/ml). This is true even for rich medium such as LB. Otherwise thymine starvation can lead to thymineless death.
• Δ(gpt-proA)62 was formerly called proA2
• galK2(Oc) was formerly called gal₂
• glnX44(AS) was formerly called su⁺_II
• glnX44(AS) was formerly called supE44
• glnX44(AS) was formerly called glnV44
• rfbC1 was formerly called rfbD1
• thiE1 was formerly called thi-1
• = kanamycin resistant
• Am = amber(UAG) mutation
• AS = amber(UAG) suppressor
• Oc = ochre(UAA) mutation
• strR = streptomycin resist.

References:

• Ahrweiler, P.M., C. Frieden 1988. Construction of a fol mutant strain of Escherichia coli for use in dihydrofolate reductase mutagenesis experiments. J.Bacteriol. 170:3301-3304