Preparation of E. Coli Minicells Containing RNA Polymerase Genes

AnF- strain of E. coli K-12 which produces DNA deficient minicells by an improper cell division has been used in developing methods to isolate plasmid DNA.I 2 By using sucrose gradient sedimentation, minicells can be easily separated from the parental cells that produce them. This E. coli mutant has a defect which is unable to synchronize DNA replication and cell division. Cell division occurs before DNA synthesis is finished, and' consequenty one of the daughter cells does not receive any DNA. These small and DNA-less cells are called minicells.I They are not viable cells, but they do maintain their biological activities for approximately 48 hrs, It is possible to prepare plasmids which contain any region of the bacterial chromosome, and these can be easily placed in minicells.

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Hacettepe Journal of Biology and Chemistry-Cover
  • ISSN: 2687-475X
  • Yayın Aralığı: Yılda 4 Sayı
  • Başlangıç: 1972
  • Yayıncı: Hacettepe Üniversitesi, Fen Fakültesi
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