Team:TU Munich/Human Practice/School Visit

Article from the school magazine

On July, 24 2012 two students from the iGEM (international Genetically Engineered Machine competition)-Team of the TU Munich visited us. We attended an interesting presentation about this competition which takes place in Boston since 2003 and they explained us that it is their research goal is to manipulate the DNA, so that the cells get other characteristics. The topic of the team is yeast (Saccharomyces cerevisiae) and how to manipulate it, so that it can produce useful ingredients naturally on his own. Yeast is normally, as we all know, used for backing and also to brew beer. It is the goal to transform normal yeast into "superyeast". Therefore herbal enzymes in the form of external DNA will be inserted. But a beer with "superyeast" in a supermarket is very unlikely. Anyway we produced our own chemical beer, which one should not drink.

They also explained us, that in the competition not only the work in the laboratory counts but also the “Human Practice”. “Human Practice” means anything what is done in the context of the project outside the university. The first experiment was DNA-extraction from plants. This meant, that we squished a banana to destroy the cells, mixed it with salt and dish liquid, which destroyed the membrane of the cell, and mixed everything with isopropyl alcohol at the end and waited. Afterwards we did another experiment: a gel electrophoresis. That is a common method to detect DNA.

We were not only informed about DNA but also how enzymes work. Therefore we squished again some fruits (this time pineapple and kiwi). The pineapple juice we needed to decompose the gelatin of gummy bears. So we put pineapple, kiwi and apple juice into bowls and added gummy bears. Unfortunately we couldn’t see the result, because it should rest for 24 hours and, of course, we forgot to look again. The last experiment this day was to pour the gel, which can’t be done in school in this way, because it lacks either on materials or on equipment or on time. The firs gel used, was from the class before us.

Anyway the day was very interesting to us and we learned a lot about iGEM, the DNA and the way enzymes work.

Corinna (16 years, student)

The school we visited

We visited the Joseph-Bernahrt-Gymnasium at Türkheim. It is a 900 pupil school in the Allgäu, where we visited a 10th an 11th class. The pupils were between 15 an 17 years old and participated in a biology or chemistry cours. We visited two classes for around 90 min each. This is the link to the school [1] and this [2] to the school magazine

What we did

We made four different experiments with the classes. First we did chemical brewing, then we extracted DNA from fruits. Another experiment was testing enzymes from fruits, by "destroying" a gummy bear with it and last but not least we did a gelelectrophoresis.

Chemical Brewing

It is based on several redox reactions, which in the end produces "yellow-brown" Iodine. Here you can see a video from this experiment produced by another school.[3]

DNA extraction from fruits

We used bananas to extract DNA from it. First the friut was smashed, then dish liquid and salt were added. Last but not least we put the "mush" in a glass already filled with Isopropanol. After 20 min we could see the DNA as white striation.

Enzyms from fruits

We used pineapple, apple and kiwi juice. Pineapple juice contains bromelain, which desintegrates the bonds within the gummy bear and therefore destroys it within 12 hours. As a control Coca-Cola was used.

Gelelctrophoresis

As a last experiment we did a complete Gelelectrophoresis with the class. First we cast an agorose gel. After solidifying, we put a marker in the pockets and switched on the electricity. The marker split up in two different colors (blue and purple) after about one hour. During the "waiting" time , we discussed with the class the use of this method in biology as detection and in forensics as genetic fingerprinting. In the end we showed a picture with an offender and three suspects as a simplified gel picture. The class directly spotted the offender amongst the lines visible on the gel and explained correctly why he appeared.