Scientific Investigation Lab Report Example | Topics and Well Written Essays - 500 words

Scientific Investigation - Lab Report Example The steps in the entire experiment protocol include (1) GFP gene construction; (2) gene shuffling and selection; (3) mutant selection; (4) mutant characterization in E. coli; (5) CH) cell expression of GFP; (6) FACS analysis; and, (7) fluorescence spectroscopy. That is, the researchers first synthesized a GFP (green fluorescent protein) gene in an E. coli construct with optimized codon usage. This was further improved using an evolutionary process of recursive cycles of DNA shuffling of the GFP gene, combined with visual selection for the brightest E. Coli colonies. Since red-shifting the excitation maximum makes detection challenging by the naked eye, UV light was used for visual screening. The independent variable in this study is the process used to improve cell fluorescence or GFP in E. coli cells. In particular, the independent variable considered the absence of GFP, the Clontech GFP, the wildtype GFP, the cycle 2 mutant GFP, and the cycle 3 mutant GFP. On the other hand, the dependent variables that were investigated for differences in this study are the fluorescence signals and excitation signals of the E. coli genes. Technically, the control group for this study is the sample with no GFP. However, the three constructs (i.e., wildtype, cycle-2 and cycle-3) were also compared against the pGFP plasmid from Clontech, with a GFP sequence reported by Chalfie et al and contains a Q80R mutation which occurred as a PCR error as well as 24 extra amino acids from the N-terminus of LacZ. Results of the research study confirms the initial hypothesis that the combination of DNA shuffling and high throughput screening would be a powerful tool in optimizing a significant number of commercially important enzymes for which selections do not