Flip One Pancake
From 2006.igem.org
Flipping One Pancake
Plan A
The plan is to construct a plasmid that contains the following. Recombination would be detected as production of Tet resistant colonies.
- Amp resistance gene as in pSB1A3
- Hin recombinase gene driven by lacP (inducible in JM109 by IPTG or lactose)
- RE (recombination enhancer)
- One Pancake test construct:
araBAD promoter, inducible with arabinose
RBS
hixL recombination site
CDS for Tet resistance in reverse direction
hixR recombination site
double forward terminator, BBa_B0015 Plate DNA-1, Spot 1I
Plan B
The plan is to construct a plasmid that contains the following. Recombination would be detected as RFP expression.
- Amp resistance gene as in pSB1A3
- Hin recombinase gene driven by lacP (inducible in JM109 by IPTG or lactose), cloned from PCR product by Davidson team
- RE (recombination enhancer), synthesized by Davidson team
- One Pancake test construct:
hixL recombination site
araBAD promoter, inducible with arabinose
hixR recombination site
RBS
CDS for mRFP
double forward terminator, BBa_B0015 Plate DNA-1, Spot 1I
Flipping Procedure (draft)
- Grow JM109 in minimal media to exponential (A600 = 0.5?)
- Induce Hin recombinase with IPTG (how much, how long?)
- Allow recombination (how long?)
- Turn off recombination by spinning down, resuspending with no IPTG
- Induce araBAD promoter and Tet resistance with arabinose (how much, how long?)
- Spread on Amp plates first, then replica plate on Tet plates, look for resistant colonies
Flipping To Do List
- Plasmid prep pSB1A3, digest with EcoRI + PstI, Pase, gel purify
- Anneal hixL, hixR, and hixC oligos, then ligate into vector, transform
- Start overnights from colonies for double forward terminator, pBAD, mRFP
- Decide on resistance gene to be flipped, do transformations