IGEM:Colombia/2007:Project Descriptions

IGEM 2006 Project
A Microbial Biosensor Device for Iron Detection under UV Irradiation

For our IGEM 2006 project the Colombian-IGEM team developed a microbial biosensor device for iron detection under UV irradiation using synthetic biology. The results of this research work have been selected for publication (now in print) on the 2007 IET Synthetic Biology Journal. Below you will find the abstract of the article and if interested in learning more about what we accomplished las year or for the complete article, please visit the IET Synth. Bio. website or the Colombian IGEM 2006 wiki.

Abstract: Biosensors are useful molecular and/or cellular tools that allow detection of the presence of different metals including iron (FeII/III) and other compounds, even at detection levels beyond the limits of conventional methods. Bacterial cells were transformed with pSB1A3 containing promoters PI and PII from Acidithiobacillus ferrooxidans rus operon and a Lacl regulated device coding a monomeric red fluorescent protein (mRFP1). An MIT BioBrick containing different parts was used to assemble the machine. The designed device was standardised for its specific detection using iron ions and/or IPTG as inputs and MRFP1 as output. Transformed cells were grown under the presence of UV radiation (360nm) or fluorescent light, and different FeII concentrations (0, 1, 50, 100 ppm). The response of the biosensor was measured by the expression of reporter protein, DNA fluorescence and/or concentration, bacterial growth, and redox potential (mV/pH) of the bacterial culture. The machine was correctly assembled and transformed in E. coli, which was observed through agarose gel electrophoresis of the plasmid and the total DNA. A ~3.506 kbp band was obtained in each case. The viability of the machine was also confirmed by the detection according to the iron concentration, and fluorescence of the reporter protein. The aim of the project was to use synthetic biology in order to develop a microbial biosensor machine assembling new protein promoter sequences for iron uptake, and some standard parts (BBa_J04450) from MIT BioBricks made in Escherichia coli DH5α strain (provided by the International Center for Tropical Agriculture, Colombia) to detect ion metals such as FeII, under a UV light environment.

IGEM 2007 Project
A Microbial Biosensor Device Assembled with Ion Channels for Iron Detection under UV Irradiation and Different Levels of Oxygen

The Colombian-Israeli team is made up of students from different cities in Colombia and Israeli high school students. The students who are currently attending different universities pursue careers within the sciences and engineering. Each and every one of us has a different personal motivation that drives us in our daily work for this year's IGEM project. As a group, we also shar a motivation that brings us together withing our team: to put into useful practice our passion for biology, math and computer science but most of all, to be creative. We want to find new solutions and new ways of solving problems and overcoming obstacles found in science through synthetic biology.

For this year's IGEM project, our team's objectives are to enhance the detection levels of the sensing device with the implementation of ion channels and to use these results as reference to develop other types of sensing devices to be used in different conditions. Biosensors are useful molecules and/or cellular tools that allow detection of the presence of different metals including iron (II/III) and other compounds, even at detection levels beyond the limits of conventional methods (Colombian IGEM. IET Synthetic Biology Journal. 2007). Last year, the Colombian IGEM team developed a microbial biosensor device for iron detection under UV irradiation using synthetic biology. This year, in association with the Israeli team, we will develop a more sensitive biosensor device, in order to detect different levels of iron, including those below that of 0.5 ppm. The device will also be tested at different levels of oxygen and UV irradiation.

Plasmid isolation, preparation of competent cells and cell transformation are being currently carried out in the laboratory at the Universidad Agraria in Bogota, Colombia. New parts designed by the Colombian group as well as parts from the MIT BioBrick will be assembled, in order to construct the genetic machine. This year, sequences from both upstream and downstream will be used for our project. One of the main new features of our device will be exposed to different environmental conditions such as oxygen levels, temperatures and varied light intensities. As we carry out all of our experiments within our laboratory, we are also developing a mathematical and computational model.