Featured in PASCO’s Advanced Biology through Inquiry Teacher Guide
This manual features 22 challenging, standards-based, inquiry lab activities for AP, IB, and honors programs.
Students transform bacteria with a plasmid that contains an ampicillin resistance gene and a gfp gene that is regulated so only some transformed cells produce the green fluorescent protein.
The discovery of bacteria transformation played an important role in understanding that DNA stores and transmits heritable information. Transformation remains important to biological research today. This lab is meant to help students solidify their understanding of the central dogma of molecular biology: the gene–protein connection.
The plasmid DNA used for the transformation contains both a gene providing resistance to the antibiotic ampicillin (ampR) and one that will cause bacteria to fluoresce (gfp). Students relate the change in the bacteria's phenotype to the genes in the plasmid. They learn that not all genes are expressed and that the fluorescence due to the gfp gene depends on a factor called IPTG. Students apply the concept of an inducible promoter to explain the results of the investigation (differential gene expression). Students also learn to calculate the efficiency of the transformation.
This experiment may require software and an interface for data collection.