Team:Birkbeck/Results

Birkbeck iGEM

The Owligos are the first-ever team entered into the international Genetically Engineered Machine (iGEM) Competition by Birkbeck, University of London. We’re a varied group of students who reflect the diversity and unique character of our institution: many of us have chosen science as a second career, having already spent some time in full-time work. For most of us, this has meant making our way through a degree while continuing to work full-time. Hopefully this kind of dedication will help us successfully navigate our way through our iGEM project.

Project Aim

Our project aims to create a new diagnostic solution that will be low-tech and cost-effective enough to allow its usage in deprived and remote communities. We’re attempting to engineer a bacteriophage lambda chassis to change its host affinity, while simultaneously adding a marker that will facilitate easy detection of a target bacterial pathogen in patient samples.

To demonstrate this approach as a proof of concept for the competition, we plan to change this affinity between different strains of E.coli; however, ultimately we hope to demonstrate that this principle could also be applied to alter the phage’s host range to other bacterial species. We could then provide a modular system capable of diagnosing a range of diseases. Of course, we haven’t chosen a simple goal. But as Birkbeck pioneers, we are determined to prove ourselves by making our project a success. We can’t wait to present the results of our work at the Giant Jamboree in September!

Under Construction

Fig. 1: Growth Curve of E. coli DH5α Strains Following Culture Optical Density of 600 nm.

Growth kinetics was initially studied using 50 mL cultures. Fig. 1 shows the growth kinetics of E. coli DH5α & derivative strains containing plasmids from the InterLab study. The growth curve shows that the E. coli strain that contains the P1-gfp expression device grows at a slower rate than the other strains investigated. At 220 minutes the E. coli DH5α P1 strain has a significantly lower OD₆₀₀ than the E. coli DH5α (P=0.023). E. coli DH5α remains very highly significantly higher in OD600 than E. coli DH5α with the P1-gfp expression device (P=<0.001). The only difference between the E. coli DH5α & E. coli DH5α positive control device is observed at 280 minutes into the growth curve (P=0.016) where the positive control has a higher OD₆₀₀. The multiple comparison table showing P values can be viewed in Table S1

Fig. 2: Growth Curve of E. coli DH5α Strains Following Culture Optical Density of 395 nm.

In order to investigate if there could be a point in the E. coli DH5α growth curve in which a signal from the GFP could be detected by absorbance, the growth curves were also conducted using the major absorption peak of GFP (wavelength 395 nm) . The growth curve data for the culture optical density is displayed in Fig. 2.

Fig. 3: Viable Count of E. coli DH5α After 60 mins.

Descriptive Statistics of 1 hour Viable Count of *E. coli* DH5α.
	N	Minimum	Maximum	Mean	Std. Deviation
Viable Count	9	1600000	3750000	2566666.67	627495.020
Valid N (listwise)	9

Table 1: Descriptive Statistics of 60 minutes Viable Count of E. coli DH5α..

Fig. 4: Viable Count of E. coli DH5α After 175 mins.

Descriptive Statistics of 175 Minutes Viable Count of *E. coli* DH5α.
	N	Minimum	Maximum	Mean	Std. Deviation
Viable Count	9	90000000	175000000	133333333.33	29154759.474
Valid N (listwise)	9

Table 2: Descriptive Statistics of 175 minutes Viable Count of E. coli DH5α.

Fig. 5: Growth Curves of Different Strains of E. coli DH5α Following Culture Optical Density at 601 nm.

Fig. 6: Growth Curves of Different Strains of E. coli DH5α Following Culture Optical Density at 501 nm.

Fig. 7: Growth Curves of Different Strains of E. coli DH5α Following Culture Optical Density at 475 nm.

Fig. 8: Growth Curves of Different Strains of E. coli DH5α Following Culture Optical Density at 395 nm.

Fig. 9: Growth Curves of Different Strains of E. coli DH5α Following Culture Fluorescence.