Plasmid_Backbone
pTG262-BB

Part:BBa_I742123:Experience

Designed by: Sarah Hollingshead   Group: iGEM07_Edinburgh   (2007-10-19)
Revision as of 21:04, 17 July 2012 by Almiwe (Talk | contribs) (Applications of BBa_I742123)

This experience page is provided so that any user may enter their experience using this part.
Please enter how you used this part and how it worked out.

Applications of BBa_I742123

  • PstI site problem: an additional PstI site is not indexed in the given sequence. Gel electrophoresis showed two fragments after digestion using PstI restriction enzyme, meaning that the plasmid contains two PstI sites instead of one.

User Reviews

UNIQ873a562f1b5c5392-partinfo-00000000-QINU UNIQ873a562f1b5c5392-partinfo-00000001-QINU


BBa_I742123 derekju -MIT iGEM 2008

We worked extensively with BBaI742103 and BBaI742123 trying to transform it into Lactobacillus delbruckii subsp. bulgaricus, Lactobacillus delbruckii subsp. lactis, and Lactobacillus acidophilus.

The DNA from the 2008 registry failed to transform and Dr. French, who entered this part, was kind enough to supply us with the plasmids. It turned out the registry wasn't able to transform this plasmid into E. Coli, probably due to non-typical growth conditions.

Instructions to transform into E. Coli:

  1. Transform using normal competent E. Coli procedures (electroporation works too, we actually had better results with electrotransforming)
  2. Select with chloramphenicol at 15 mg/l
  3. Allow cells to grow for at least TWO DAYS, they take a while to grow and have a low transformation efficiency
  4. There may high background growth, (probably due to the relatively low antibiotic concentration and length of the incubation), make sure to verify that you have miniprepped the actual pTG plasmid. Since this is the plasmid with RFP dropped in, you can simply choose the red colonies on the plate.


Our project aimed to transform Lactobacillus, a lactic acid bacteria. pTG262 is reported to be able to replicate in Lactobacillus. However, we tried to electroporate pTG262 into Lactobacillus, and unfortunately we were unsuccessful. According to the papers we read and our own experience, the most successful way to transform Lactobacillus, or similar lactic acid, gram-positive bacteria is via electroporation. We tried various protocols obtained from papers (all of which reported Lactobacillus having a very limited range of transformable plasmids, due to possible DNA restriction). To view the methods and protocols we used to try to transform Lactobacillus, please visit the MIT 2008 iGEM team wiki. In conclusion, we were unable to transform plasmid pTG262 into Lactobacillus, and are reasonably confident, that pTG262 CANNOT be electrotransformed into Lactobacillus. Although there are other avenues to possibly introduce foreign DNA into Lactobacillus, electrotransforming with plasmids remains the easiest way. FOr those looking to transform Lactobacillus, other plasmids (such as pJK650 or pLEM415, both of which will be supplied to the registry) should be considered.


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