CGSC Strain#: 6891
Strain Designation: M239      Source of Strain: S. Brenner
Sex: F' Episome/Plasmid: F8-14
   Plasmid Markers/Mutations: galK42(Am)
Chromosomal Markers: araBAD-38(Am), Δ(codB-lacI)3, tsx-68, galK42(Am), galE54(GalS), λ^-, tyrT66(AS), trpA49(Am), relA1, spoT1
Strain Comments:

• Δ(codB-lacI)3-- is a deletion of the entire lac operon, from the strain Hfr 3000 X74 of Jacob. Refs. on extent of deletion: Sung et al.1987,J.Bact.169:2639; Gerdes et al.2001
• Δ(codB-lacI)3-- Shown by Ferrandez et al. 1997 to extend to mhpD
• Δ(codB-lacI)3-- Shown by Durfee et al. to extend from codon 292 of yahG through mhpE
• galK42(Am)-- is Brenner's gal^-_U42am.
• trpA49(Am)-- is the amber mutation formerly called trp^-_8am by Brenner.
• spoT1-- In addition to the 6bp insertion, there is a C to T transition resulting in an H257Y substitution.
• Δ(codB-lacI)3 was formerly called Δlac74
• Δ(codB-lacI)3 was formerly called Δ(lac)3
• Δ(codB-lacI)3 was formerly called Δ(yahG-mhpE)
• Δ(codB-lacI)3 was formerly called X74
• Δ(codB-lacI)3 was formerly called DE(lac)6
• tyrT66(AS) was formerly called su⁺_III
• tyrT66(AS) was formerly called supF66
• Am = amber(UAG) mutation
• AS = amber(UAG) suppressor
• GalS = UDPGal accum.toxic if GalKRP+
• Am = amber(UAG) mutation

References:

• Russell, R.L., J. Abelson, A. Landy, M.L. Gefter, S. Brenner 1970. Duplicate genes for tyrosine tranfer RNA in Escherichia coli. J.Mol.Biol. 47:1-13