Bacterial Transformation

Competent Cells

Bacterial cells that are treated to allow them to take up plasmid DNA.

Plasmid DNA

Small, circular DNA molecules used in genetic engineering to introduce new genes into bacteria.

Heat-shock

A technique used to open the pores of competent cells by exposing them to a high temperature.

SOC Medium

A nutrient medium used for the recovery of transformed bacteria after heat-shock.

Colony-forming units (CFUs)

A measure of viable bacterial or fungal cells in a culture.

Transformation Efficiency

The number of transformed cells per µg of plasmid DNA.

Transformation Efficiency Formula

$$\text{Transformation Efficiency} = \frac{\text{Total number of CFUs}}{\text{Amount of plasmid DNA in µg}}$$

Incubation on ice

A step in the transformation process that helps stabilize the competent cells after mixing with plasmid DNA.

Selective Agar Plates

A culture medium that contains specific antibiotics to select for transformed cells.

Shaking at 200 rpm

A process during the incubation to aerate the culture and promote cell growth.