Try the new EcoliHub and let us know what you'd like to see.

From EcoliWiki

MG1655 is the strain chosen by the Blattner group for the first published sequence of a wild-type laboratory strain of E. coli K-12^[1]. Although MG1655 was chosen for having few genetic manipulations from the archetypal E. coli K-12 strain, most strains used in E. coli molecular genetics were not directly derived from MG1655.^[2][3]

Alternate Names

Chromosomal Genotype

F^-, lambda^-, rph-1

Plasmids

none

Phage

none

Phenotypes

Mild pyrimidine auxotrophy. Although MG1655 can grow in minimal media lacking uracil, adding uracil to the media increases the growth rate by 10-15%.^[4]

Construction

The original K-12 wild-type strain from the Stanford collection contained both the F plasmid and phage lambda. MG1655 was constructed by curing that strain using acridine orange and UV. ^[2][3]

Notes

This strain is available from the Coli Genetics Stock Center.
rph-1 is a 1 bp deletion that results in frameshift over last 15 codons and has polar effects on pyrE, leading to suboptimal pyrimidine levels on minimal medium. ^[4]

Isolates of MG1655 from different labs are genetically variable^[5]. Although the Stock Center isolate used by Soupene et al.^[5] contained a deletion around fnr, the isolate currently being distributed by the CGSC is fnr⁺. MG1655 isolates obtained from the stock center at various times prior to 2000 are also fnr⁺ (D. Siegele, pers. comm.).

See also

• Information about MG1655 at UW-Madison
• Genes in MG1655
• RefSeq record

References

See Help:References for how to manage references in EcoliWiki. ^[6]

1. ↑ Blattner FR et al. (1997) The complete genome sequence of Escherichia coli K-12. Science 277: 1453-74 PubMed EcoliWiki page
2. ↑ ^{2.0 2.1} Bachmann BJ (1972) Pedigrees of some mutant strains of Escherichia coli K-12. Bacteriol Rev 36: 525-57 PubMed EcoliWiki page
3. ↑ ^{3.0 3.1} Derivations and genotypes of some mutant derivatives of Escherichia coli K-12. In: Neidhardt, FC et al. (1996) Escherichia coli and Salmonella typhimurium: Cellular and Molecular Biology (ASM Press, Washington, DC)
4. ↑ ^{4.0 4.1} Jensen KF (1993) The Escherichia coli K-12 "wild types" W3110 and MG1655 have an rph frameshift mutation that leads to pyrimidine starvation due to low pyrE expression levels. J Bacteriol 175: 3401-7 PubMed EcoliWiki page
5. ↑ ^{5.0 5.1} Soupene E et al. (2003) Physiological studies of Escherichia coli strain MG1655: growth defects and apparent cross-regulation of gene expression. J Bacteriol 185: 5611-26 PubMed EcoliWiki page
6. ↑ Guyer MS et al. (1981) Identification of a sex-factor-affinity site in E. coli as gamma delta. Cold Spring Harb Symp Quant Biol 45 Pt 1: 135-40 PubMed EcoliWiki page