No desire to wait for evolution | TIME ONLINE

        
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                                                                Page 1 – No desire to wait for evolution
                            
                                
                                        
                                                                Page 2 – Antibodies as the most accurate weapon of the human immune system
                                    
                            
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Evolution is a magic bag. She has primal bacteria
spawned in 100-degree warm water,
Jellyfish that light their way through the ocean – and of course extreme
complex creatures like humans. Hundreds of thousands of chemical reactions
Expire every millisecond in our bodies. And only because certain
Proteins, enzymes, they catalyze. It's these protein molecules that, if you like,
at the bottom of all life and yet only by accident, through the
Evolution is how they are. The problem: they often take thousands of years to become effective in what they do
improve.
                
            Not fast enough for what this year's Nobel laureates had in mind with such enzymes. They saw that nothing changes the biological components so precisely and makes them as powerful as evolution itself. At the same time, they did not feel like waiting until nature produced variants that could be optimally used in medicine or industry. The biochemist Frances Arnold on the one hand and the biologist George Smith and the molecular biologist Sir Gregory Winter on the other are honored with the highest honors in science because they deliberately exploited the power of evolutionary chance. They laid the foundation for a greener chemistry, biofuels and completely new, powerful drugs: highly effective antibodies. They let the evolution in test tubes in time lapse run. What takes millennia in nature happens in hours in the lab. The basis for medicines with antibodies Enzymes are highly complex protein molecules that initiate chemical reactions – with a variety of tasks: they break down toxins, so that the
Cells of the human body do not suffer, they stick sugar molecules
to each other to create energy storage or make toxic substances to
Disintegrate pathogens. Enzymes consist of chains of mostly several hundred amino acids. Their blueprints are recorded in genes. Will you
Made from bacteria or human cells, they wrap and twist them
many times before they really take effect. Over millions of years, the genes and thus the function of such enzymes changed. No matter if in humans, porcupines
or the malaria parasite – those who worked well, or at least did not harm, always survived best. Evolution, if you like that
wants, is constantly busy to produce better enzymes.
            
                    
        © Michael Heck
            Jakob Simmank
            Editor in the department of knowledge, ZEIT ONLINE
        
    

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This was also stated by the American Frances Arnold. She did her award-winning research at the prestigious California Institute for
Technology (Caltech), where she still works today. When she started this work in the eighties, she was
already aware of the power of enzymes in chemistry. With a lot of headache
They tried to penetrate the structure of the enzymes and targeted them
to make it more effective. Something Arnold later called "one
rather arrogant approach. "She went another way and
used the power of evolutionary chance to find better enzymes. Something,
which was later called "directed evolution".
                
            The power of chance tamed Arnold's research began with the enzyme subtilisin, which
a pair of scissors cuts other protein chains and, for example, into
Detergent is included (FASEB Journal: Arnold, 1993). She tried that
Change enzyme so that it is in a particular solvent in which it
until it functioned only tolerably, unfolded its full power. To that
The biochemist isolated the gene of subtilisin and made sure that its
Genetically mutated genetic material – as usual in the course of evolution. Then examined
They used the resulting new proteins to determine how well they worked and chose the best ones. Apart from chance, selection is the second driver of evolution. this
Step by step, the researcher repeated four times and put a library
the mutant enzymes. At the end there was a protein complex that was 256 times as active as
the starting enzyme (see picture). Arnold had rebuilt the evolution.
                
            
                                    
        
        The principle of directed evolution works as follows: (1) Random mutations are induced in the gene for the enzyme to be altered. (2) The genes are inserted into bacteria that use them as a template and randomly produce mutant enzymes. (3) It is necessary to test the modified enzymes. Researchers select those that most efficiently drive the desired chemical reaction. What is not good, is disposed of. (4) Then add new random mutations into the genes of the chosen enzymes. The cycle starts again.
                        © ohan Jarnestad / The Royal Swedish Academy of Sciences
The approach she proposed is that until today
valid. Arnold's life's work is to perfect her with other researchers
to have. One of them is William Stemmer, who died already in 2013 and
probably that's why today was not honored. Nobel prizes are not awarded posthumously, according to the statutes. Stemmer introduced DNA shuffling. In this method, the DNA, so the genetic material, similar enzymes, but from different organisms
used for directed evolution.
                
            Enzymes created by directed evolution,
Already used in many areas of industry and medicine: in the production of biofuels, in
the environmentally friendly development of chemicals, in the detoxification of
Industrial waste or for the manufacture of medicines. And right there
the other two this year's Nobel Laureates come into play: the American George P. Smith and the British Sir Gregory P. Winter.

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