Team:Goettingen/NeuTest

From 2012.igem.org

Welcome to iGEM Göttingen

iGEM is an international competition hosted by the MIT in Boston, USA, for undergraduate students of disciplines related to molecular biology. iGEM stands for International Genetically Engineered Machine competition. One the one hand, it targets to combine aspects of education and social collaboration among undergraduate students, on the other hand, it provides a library for standardized and interchangeable parts which can be used in living systems, particularly in model organisms like E. coli. Student groups from all over the world will receive a requested kit of biological parts, also called "biobricks", and work over the summer on an individual research project. Every year, the "Registry of Standard Biological Parts" is upgraded with further biobricks by the participating iGEM teams. These biobricks will be accessible to the iGEM community in the following years in order to use these parts for their own projects.

The iGEM competition started in 2003 as a course for students of the MIT only. 2011, already 165 universities from all over the world competed against each other. This year, it is the first participation of the University of Goettingen, Germany. The iGEM competition is a great opportunity for students to gain and improve a multitude of skills that are necessary during a carrier as a molecular biologist. Such skills would be planning and organizing a project, including fund raising and team recruitment, coordination of lab work, designing experiments and working together as a team. Next to intensive lab work during the summer, also literature search and well-structured documentation of the experiments is crucial. Moreover, safety for humans and environment is key.

Homing Coli

Escherichia coli is a commonly used bacterial model organism. It has lots of beneficial traits, e.g. a short generation time and it can be easily manipulated. Most E. coli strains that are used in laboratories do not exhibit high motility. The crucial element for motility is the flagellum, which is rotated by a molecular motor within the cell wall. Consequently, these are reduced in cultivated E. coli strains.

Our goal is to create an E. coli strain with increased swimming motility on special agar plates. Therefore, we will overexpress regulators and parts of the E. coli flagellum in cultivated strains in order to enhance bacterial swimming ability. The fastest E. coli strains will be selected and further improved. At the same time we will then be able to create an effective motility-selection method.

Now, you are probably wondering what the advantage of a fast E. coli might be. The beneficial fast phenotype can be combined with the ability of this bacterium to sense specific compounds in their environments. Chemo-receptors enable it to move towards or along gradients of such substances. We will use PCR-based site directed mutagenesis on the E. coli Tar receptor. The combination of speed and chemotaxis allows us to identify E. coli strains, which can sense interesting compounds. Thereby, an easy method for the detection of pollutants, toxins or even tumors could be provided.

Clive S. Barker et al. (2004). Increased Motility of Escherichia coli by Insertion Sequence Element Integration into the Regulatory Region of the flhD Operon. Journal of Bacteriology, Vol. 186: 7529-7537.

Synthetic Biology

Synthetic biology is an interdisciplinary scientific area that has recently developed. It links various fields of science like biology, chemistry, physics, molecular genetics, informatics and engineering.

Due to this combination the relation of biological design and function can be investigated from an entirely new perspective. The previous approach was limited to the examination of a structure and its function and the attempt to explain how they correlate. Recently, the reverse strategy is applied. Biological parts are specifically designed and constructed according to a desired function. These parts are characterized by a standardized modular design that facilitates their handling. The subsequent introduction of the synthetic constructs to living cells can either cause the replacement of original cellular components or result in additional elements that act cooperatively or more or less autonomously (see fig. 1).

Nagarajan Nandagopal and Michael B. Elowitz. (2011). Synthetic Biology: Integrated Gene Circuits. SCIENCE, Vol. 333: 1244-1248.

Another very important and necessary feature of biological parts is orthogonality, which means in this context that independent devices can be combined unrestrictedly. This principle derives from the area of engineering and aims to alter subsystems, without impeding others.

This way cells can be modified as requested, resulting in a predictable behaviour. Among others, this technique can be beneficial for the effective production of certain substances, like biofuels or antibiotics.