Evolution for the Protection against Global Warming
In approx. 4 million years, evolution has given almost every environment its organisms the enzymes needed for survival. Whether in boiling hot thermal springs or in the frosty deserts of Antarctica: no spot on our planet is not covered with an abundance of life. A few „pioneers“ survive even in the inhospitable heights of the exosphere, the outer layer of the earth’s atmosphere that borders the unending expanses of the universe.
These are mostly primitive microbes that, because of their triviality, have found the perfect adaptations to the regions of our planet most hostile to life.
However, in this modern industrial world of man, bacteria and other microbes are not just fighting for the survival of their kind. They will hopefully begin to put the talents that were given to them from nature to use for mankind in large fermenters. They break up complex molecules like starches or fats, soften fruits (in order to be able to press more juice out of them) or ferment glucose into ethanol that is added to fuel.
The enzymes produced by bacteria that accomplish these tasks have adapted to the original environmental conditions of their habitats but not to those of the fermenter. A natural adaptation, as through evolution, is hardly possible in this situation, especially because the bacteria being used in the fermenter are not being put under stress. The environmental conditions have been adapted to suit them.
A common amylase, an enzyme that breaks starch down into glucose, has a current ideal working temperature of 80°C. To heat the large amounts of starch used in industrial contexts to this temperature, an unbelievable
amount of energy must be expended. Every degree of temperature less that is needed for amylase to do its work would save energy and CO2. In the automobile industry, for example, researchers work for months to improve the efficiency of a motor by one half of a percent. Why not pay the same amount of attention to the optimization of the use of enzymes?
The amount of energy that could be saved can be understood with the following example:
The largest bio-ethanol plant in Austria produces 4000,000t of starch filled materials each year and an Austrian citric acid plant ferments 250,000t of cornstarch a year with amylase.
The a-amylase used by the company Novozymes, which is produced with the help of transgene bacteria, has an optimum temperature of 82°-86°C. A new, temperature optimized amylase that, for example, could work just as well at 60°C could, according to our careful calculations, save more than 50 terajoules (1012) just by being used at the two plants mentioned above. That is the equivalent of more than 3,000 average Austrian households.
But how is it possible to make an enzyme adapt itself to these conditions?
It is already standard practice to "implant" coded enzymes from other organisms into bacteria, which allows for a desired product to be produced easily and economically by the rapidly
reproducing bacteria. It is also possible to greatly raise the production rate of an enzyme in a similar way with the use of so-called "promoters".
However: directly manipulating the structure of proteins and its relating functions is complicated with the current tools available in genetic engineering. Practical tools are made available by synthetic biology, a new branch of modern molecular biology. With its help it will be possible to optimize and design enzymes and organisms to their designated tasks.
We, the students of the HLFS Ursprung, have made it our goal with this project to change an amylase’s blueprint by introducing non-canon, synthetic amino acids (ethionine and norleucine) into its structure in the hopes of lowering its "working temperature." Two scientists at the Max-Planck-Institute for Biochemistry in Martinsried lent us their technical know-how and taught us the basic principals involved.
But an "enzyme upgrade" is not so easy. If one changes a protein in this way, there can also be unwanted changes as well. The enzyme could, for example, simply no longer function or could work less efficiently. If the introduction of new building materials into an amylase were to work, we could at least show that this method allows the manipulation of the functionality of an amylase.
We began to work in a research area that should be getting more of society’s attention for its incomprehensible amounts of possibilities for change in the future, in both an economic sense as well as a legal one.