CGSC Strain#: 4424
Strain Designation: Y40      Source of Strain: E.M. Lederberg
Sex: F+ Chromosomal Markers: fhuA24, bio-1(Unst), spoT1, metB1, creC510
Strain Comments:

• lyophil opened 8/31/05
• bio-1(Unst)-- : This marker apparently reverts at high frequency
• spoT1-- In addition to the 6bp insertion, there is a C to T transition resulting in an H257Y substitution.
• creC510-- The constitutive phenotype is due to an R77P amino acid substitution
• creC510 was formerly called phoM510
• Const = constitutive
• Unst = unstable

References:

• Lederberg, J 1949. Aberrant Heterozygotes in Escherichia Coli. 35(4):178-84.
• Lederberg, E.M. 1952. Allelic relationships and reverse mutation in Escherichia coli. Genetics 37:469-483
• Gosting, D.C., J. Lederberg 1956. Biotin requirement of cultures derived from E. coli K-12 strain 58. Microbial Genet.Bull. 13:13-14