CGSC Strain#: 4396
Strain Designation: KL20      Source of Strain: M.C. Cappello
Sex: F+ Chromosomal Markers: λ^-, e14-, relA1, spoT1, thiE1
Strain Comments:

• This strain is a spontaneous F+ revertant of Hfr 3000.
• e14--- : Loss of the e14 element makes the strain McrA^-.
• spoT1-- In addition to the 6bp insertion, there is a C to T transition resulting in an H257Y substitution.
• thiE1 was formerly called thi-1

References:

• Low, K.B. 1973. Rapid mapping of conditional and auxotrophic mutants of Escherichia coli K-12. J.Bacteriol. 113:798-812