E. coli Genetic Resources at Yale
CGSC, The Coli Genetic Stock Center

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Strain MX419

• CGSC#: 5350
• Strain Designation

  Designation	Source	Preference
  MX419	Oeschger M.P.	1

  
  
• Sex(Hfr,F+,F-,or F'): Hfr
• Hfr Point of Origin#: 44
• PO Map Position: 46.69
• Direction of Marker Transfer: Counterclockwise
• 9 Mutations:

  Mutation	Location	Certainty	Display
  lacZ2210(Am)	7.81	1	lacZ2210(Am)
  tsx-85	9.28	1	tsx-85
  LAM-	17.40	1	λ-
  serU74(ts,AS)	44.01	1	serU74(ts,AS)
  gyrA21(NalR)	50.33	1	gyrA21(NalR)
  relA1	62.71	1	relA1
  rpsL183(strR)	74.84	1	rpsL183(strR)
  spoT1	82.34	1	spoT1
  thiE1	90.34	1	thiE1

  
  
• Comments:
  • supD74 (TS) is not very efficient in MX419. The rpsL183 allele inhibits the suppressor efficiency four-fold in this strain.
  • 1.This strain was constructed to provide a source of the allele supD74(Ts). It transfers supD early in conjugation. Oeschger recommends using Val^R counterselection
  • 2.in conjugational transfer from MX419.
  • The presence of the suppressor can be monitored by checking for a Lac⁺ phenotype at 30C and a Lac^- phenotype at 40C.
• References:
  • Oeschger, MP, SL Woods 1976. A temperature-sensitive suppressor enabling the manipulation of the level of individual proteins in intact cells. Cell 7(2):205-12.
  
  

  Printable Strain Report