pBAD202 Directional TOPO™ Expression Kit

While the amount of L-arabinose can vary depending on your expression experiment, we suggest performing a pilot expression experiment with varying amounts of L-arabinose from 0.00002% to 0.2%.

Top10

Advantages:
- Saves time, can go directly from cloning to expression.
- The glycerol stock is more stable because these strains are endA- and recA-.

Disdvantages:
- This strain is not protease-deficient. Therefore, the protein may be degraded.

LMG194

Advantages:
- Grows well in minimal media, except M9.
-Have to transform the plasmid into the cells just for expression.
-RM medium with glucose to ensure low basal level of protein.

Disadvantages:
- Not protease-deficient. Therefore, the protein may be degraded.
- The glycerol stock may not be stable because this cell strain is not recA- or endA-.

We recommend using a competent cell strain that is araBADC- and araEFGH+, allowing transportation of L-arabinose, but not metabolizing it. This is important for expression studies, as the level of L-arabinose will be constant inside the cell and will not decrease over time. We offer our TOP10 competent cells, or our LMG194 E. coli strain.

The pBAD vectors contain a forward and reverse pBAD primer flanking the gene of interest. The sequences are as follows:

pBAD forward primer: 5'-ATGCCATAGCATTTTTATCC-3'

pBAD reverse primer: 5'-GATTTAATCTGTATCAGG-3'

Here are the cap colors:

- pBAD/His A: Red

- pBAD/His B: Orange

- pBAD/His C: Yellow

- pBAD/His LacZ: Green

- pBad/gIII A: Yellow

- pBad/gIII B: Green

- pBad/gIII C: Blue

- pBAD/gIII/calmodulin: Purple