Toxin-induceret celledød i E.coli / Toxin-induced cell death in E. coli

Sigrid M Andersen, Morten E Møller, Joan Tønning, Anne Lykke, Kim Olsson & Rune Olsen

Studenteropgave: Semesterprojekt

Abstrakt

Abstract I dette projekt undersøges det, hvorvidt det er muligt at inaktivere E. coli bakterier vha. en regule-ringsmekanisme. Denne mekanisme involverer et toxin, RelE, og en tryptofanpromotor. Tryptofan-promotoren er en DNA-startsekvens, der gør at tryptofan produceres, når dette ikke er til stede i omgi-velserne. Ved at implementere toxinet nedenfor promotoren i et pUC18 plasmid, vil promotoren blive startsekvensen for relE, når der er mangel på tryptofan i cellen. Det gensplejsede plasmid kaldes pGF2 og indsættes i en E. coli bakterie, efterfølgende udsættes bakterien for tryptofanmangel. Formålet er at få bakterien til at dø heraf. Konklusion på forsøget er, at bakterier med pGF2 svækkes. I nogle tilfælde opnås en statisk død med døden til følge. This project investigates the possibility of killing E.coli bacteria by introducing a suicidal mechanism. This suicidal mechanism involves the toxin, RelE, and a trypthophan promotor. The trypthophan pro-motor is an initialising DNA-sequence, which starts the production of tryptophan, when this is not present in the surroundings. By implementing the toxin downstream of the tryptophan promotor in a pUC18 plasmid, the promotor will initialise the synthesis of RelE, when there is lack of trypthophan in the cell. This genetically modified plasmid is called pGF2 and inserted in E.coli bacteria. Afterwards the bacteria’s are exposed to a growth medium lacking trypthophan. The purpose is to make the bacte-ria die from this. The conclusion is that the bacteria with pGF2 are weakened. In some occasions a stationary death is obtained which can be fatal for the bacteria.

UddannelserBasis - Naturvidenskabelig Bacheloruddannelse, (Bachelor uddannelse) Basis
SprogDansk
Udgivelsesdato1 jun. 2005

Emneord

  • promotor
  • Tryptofan
  • prokaryot
  • cell death
  • toxin
  • bacteria
  • biological containment
  • relE
  • RelE
  • growth inhibition
  • tryptophan