CGSC Strain#: 4380
Strain Designation: KL237      Source of Strain: M.C. Cappello
Sex: Hfr    Point of Origin#:    Map Position: Chromosomal Markers: fhuA22, phoA4(Am), serS30, serS15(ts), ompF627(T2R), fadL701(T2R), relA1, pitA10, rrnB-2, mcrB1, creC510
Strain Comments:

• serS30 is a second mutation (not actually shown to be at the serS locus which results in a partial restoration of the serS⁺ phenotype. The strain is no longer TS for growth.
• phoA4(Am)-- is Garen's phoAS26 . It is suppressed by leuX151, glnV33(=supE33) and serU132(=supD32).
• serS15(ts)-- is a temperature-sensitive mutation.
• rrnB-2-- : loss of spacer loop sequence
• creC510-- The constitutive phenotype is due to an R77P amino acid substitution
• creC510 was formerly called phoM510
• Am = amber(UAG) mutation
• Const = constitutive
• T2R = T2 Resistant
• ts = Temperature Sensitive

References:

• Low, B, F Gates, T Goldstein, D Soll 1971. Isolation and partial characterization of temperature-sensitive Escherichia coli mutants with altered leucyl- and seryl-transfer ribonucleic acid synthetases. J. Bacteriol. 108(2):742-50.