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

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Strain DH20

• CGSC#: 6818
• Strain Designation

  Designation	Source	Preference
  DH20	Hanahan D.	1

  
  
• Sex(Hfr,F+,F-,or F'): F'
• 10 Mutations:

  Mutation	Location	Certainty	Display
  glnX44(AS)	14.99	1	glnX44(AS)
  LAM-	17.40	1	λ-
  rfbC1	45.43	0	rfbC1
  gyrA96(NalR)	50.33	1	gyrA96(NalR)
  recA1	60.80	1	recA1
  relA1	62.71	0	relA1
  endA1	66.57	1	endA1
  spoT1	82.34	0	spoT1
  thiE1	90.34	1	thiE1
  hsdR17	98.74	1	hsdR17

  
  
• Comments:
  • This F-prime comes from the strain X91, which carries a derivative of F128-10 that was designated F128-17. F128-17 and F128-18 are probably the same F-prime, extending from ( proB-lac) and carrying lacIp-4000(lacI^Q).
• Episome/Plasmid: F128-18

  Plasmid Markers/Mutations:
  lacIp-4000(lacIQ)

• References:
  • Hanahan, D. 1983. Studies on transformation of Escherichia coli with plasmids. J.Mol.Biol. 166:557-580
  
  

  Printable Strain Report