Lesson 4: Extension Activity, Calculate Transformation Efficiency

 (Athira)

1. Determining the Total Number of Green Fluorescent Cells
   
   Total number of colonies = 41
   
2. Determining the Amount of pGLO DNA in the Bacterial Cells Spread on the LB/amp/ara Plate
   
   a. Determining the Total Amount of pGLO plasmid DNA
   
   Total # of pGLO DNA (μg) = 0.08 x 10 = 0.8 (used to calculate transformation efficiency)
   
   b. Determining the fraction of pGLO plasmid DNA (in the bacteria) that actually got spread onto the LB/amp/ara plate
   
   Fraction of DNA = 100/510 ~ 10/51 (used to calculate transformation efficiency)
   
   pGLO DNA spread (μg)= 0.8 x 10/51 = 0.15682745 μg
   
   

   # of colonies on LB/amp/ara plate =	41
   Micrograms of pGLO DNA spread on the plates	0.16

   
   
   
   
   
   Transformation efficiency= 41/0.16= 256.25 transformants/ μg
   
   

Analysis

How would scientists report 10,000 transformants/ μg in scientific notation?

1.0 x 10⁴  transformants/ μg

How would scientists report 40,000 transformants/ μg in scientific notation?

4.0 x 10⁴ transformants/ μg

How would scientists report 960,000 transformants/ μg in scientific notation?

9.6 x 10⁵ transformants/ μg

Report your calculated transformation efficiency in scientific notation.

1.56 x 10² transformants/ μg

Use a sentence or two to explain what your calculation of transformation efficiency means.It means the # of E.coli bacteria that efficiently transformed or had the gene of interest.

How does your transformation compare to the general agreement set by biotechnologists?

# of colonies on LB/amp/ara plate =	41
Micrograms of pGLO DNA spread on the plates	0.16

           




We did not reach their agreement, we are under by about 543 transformants/μg.

Fill in the following chart and show your calculations to your teacher:

# of colonies on LB/amp/ara plate = 227

Micrograms of DNA spread on the plates = 0.157 μg

Transformation efficiency = 1445.86 transformants/μg

0.08 x 10= 0.8 μg

100/510 x 0.8 = 0.157 μg

227/0.157 = 1445.86 transformants/μg

Extra Credit Challenge

300/0.157 = 471 colonies of bacteria