Low Level Expression

For our in vivo work, we needed to be able to express reflectin at low levels, and control the level of expression reliably. Therefore, we expressed reflectin under an arabinose inducible promoter (pBad) on a low copy plasmid (PSB3K3) in cells with a titratable response to arabinose.

Constructs

In this experiment we used confocal microscopy to compare distribution of Reflectin A1 when it is expressed at high and low levels in E.coli cells.

Observations

When reflectin was expressed on a low copy plasmid, we saw fewer inclusion bodies than when expressed on a high copy plasmid.

Induction

Using a plate reader, we measured the expression of reflectin-GFP over time after inducing with arabinose. We saw that reflectin does not appear to be particularly toxic to E. Coli.