ML43
(Bacterial strain #61922)

• Purpose: C43(DE3)-based E. coli amino acid auxotrophic host strains used for selective isotope labeling. cyo ilvE avtA aspC hisG argH metA lysA thrC asnA asnB genes deleted.
• Depositing Labs: Robert Gennis, Toshio Iwasaki
• Publication: Lin et al Methods. 2011 Dec;55(4):370-8. doi: 10.1016/j.ymeth.2011.08.019. Epub 2011 Sep 8.

Backbone

• Vector backbone: none

Growth in Bacteria

• Bacterial Resistance(s): None
• Growth Temperature: 37°C
• Growth Strain(s): ML43 (cyo ilvE avtA aspC hisG argH metA lysA thrC asnA asnB)
• Copy number: Unknown

Gene/Insert

• Gene/Insert name: none

Resource Information

• Supplemental Documents:
  • PCR primers
  • PCR data M43

Terms and Licenses

• Academic/Nonprofit Terms:
  • UBMTA
• Industry Terms:
  • Not Available to Industry

Depositor Comments

Genotype = cyo ilvE avtA aspC hisG argH metA lysA thrC asnA asnB
Precursor strain = ML42
modified from the parent Escherichia coli C43(DE3) strain
Selective amino acid labeling (and/or requirement) = (Ala#), Ile, Leu*, Tyr#, Val, His, Arg, Met, Lys, Thr, Asn

*In the presence of 0.4-1 mM Tyr, tyrB is repressed and Leu is required for growth in minimal medium. This strategy can only be applicable for a short-term cultivation but not suitable for a long-term cultivation for heterologous expression of foreign genes [Methods 55, 370-378 (2011)].

#In the presence of 0.4-1 mM Tyr, tyrB is repressed and Tyr is required for growth in minimal medium. Under these conditions, this strain can also be used for selective labeling of the input Tyr and/or Ala label(s), although minor diffusion of the input label(s) can occur. Note that this strategy can only be applicable for a short-term cultivation but not suitable for a long-term cultivation for heterologous expression of foreign geness [Methods 55, 370-378 (2011)].

Each target gene was deleted from the chromosome of C43 (DE3) E. coli strain using λ-Red recombination system.

Supplemental documents contain a list of PCR primers used for verification of each knocked-out gene as well as an image showing PCR results for this strain.