Synthetic biology: Robbery of creation

A severe fever is spreading in many laboratories around the world, infecting biologists, physicists, chemists and computer experts.

Symptoms: want to reproduce life in a test tube or on a computer, create a living creature from chemical components . inert, or "mess" into life to create . new creatures! This fever is called synthetic biology!

Do not confuse synthetic biology with prebiotic chemistry, which seeks to create the first life germ by mixing in the simplest 'soup pot' of molecules. Unlike the artificial life of the 1970s, finding ways to make machines smarter.

Although borrowed from classical gene manipulation techniques, synthetic biology is still far away, with greater ambitions and more complicated uses. With this new discipline, biology has stepped straight into the field of 'project design'. Biologists are no longer just those who understand the structure of life, but also use it as a means to increase human ability to control the universe. Professor Theodor von Karman once said: 'Scientists discover things that exist, engineers create unprecedented creatures!'

Reprogramming germs!

They are engineers, computer experts, chemists, biologists . They want to understand and control nature. They think life is a program encoded in DNA molecules. Change, rewrite this code will force nature to do what humans have never done, even nature has not done it yet! And they are violently attacking the germs, with a technique called reprogramming.

In 2000, Michael Elowitz and Stanislas Leiber, of the division of molecular biology at Princeton University, USA, made the gray-colored Escherichia coli bright . flashing! At the same time Ron Weiss makes it a color that changes to the environment, turning red when some molecules appear and blue when not available. And Christopher Voigt of the University of California turned it into . photographic film! Depending on how strong or weak the light is, it is white or black!

Each time, these researchers view genes as transistors of an electronic circuit. Nuclicic acids A, C, G, T of DNA molecule replace the 0 and 1 series of computers. But although it is easy to assemble DNA molecules, germs do not always create what the researcher wants. Ron Weiss recounted: 'It took years to design a system that could work.'

The subject is still forming. It also had to standardize the gene blocks, eliminate the damage, theorize some results. At Berkeley University, Jay Keasling plans to synthesize the inside of the microorganism artémisine an anti-malaria molecule, which is difficult to manure. Christopher Vight again created the 'smelling' germ of cancer.

Others dream of creating a decontamination bacterium and toxic substances of the environment. Ron Weiss concluded: 'We are in the same period as when we started the computer. Application is unpredictable '.

Create virus

Genetics lets go beyond changing some genes of a bacterium. It can pair genes one by one and create life for the virus. For example, in 2002, the team of Eckard Wimmer, of New York University, created a polio virus from a simple sequence of genes at Stony Brook Laboratory. They paired the 7,500 roots of a DNA molecule, as if they were piercing jade beads to create a string.

Not working while outside the cell, this artificial virus causes a virus-like disease at the time of transplanting into the mouse. Eckard Wimmer states: 'We want to prove: viruses are just chemicals, a simple formula! Although polio is considered to be eradicated, it is clear that no virus will disappear completely. ' From a sequence of DNA molecules, one can create life for an organism.

That was what Professor Jeffrey Tautenberg's group, the American Military Hospital, did in late 2005. From a stored lung of a woman who died in the Spanish pandemic in 1918, he reproduce flu viruses. This epidemic killed 50 million people at that time.

Neither Wimmer nor Tautenberg are bioterrorists. Their goal was to just break the virus, to understand its violent origin, to predict the evolution and of course to make vaccines. Is there a better way to create viral roots in the lab?

Thus, the 'creators' of Spanish flu may return to the origin of the virus, possibly as a bird, but unlike the H5N1 virus that is currently rampant around the world. In addition, Eckard Wimmer plans to use these synthetic organisms to attack diseases such as Nil malaria or meningitis.

These two pioneering research groups will certainly be 'annoying' because it is increasingly easier to synthesize larger genes. In 2002, it took a year to create a virus that caused polio. Now only a few weeks! In 2003, American biologist Craig Venter synthesized 5,000 roots of a virus capable of killing germs, within 14 days.

Since then the records have been successively broken. At the end of 2004, at Harvard University, Professor George Church's group assembled 14,500 roots for a sample of DNA molecules. All are equivalent to amino acids in proteins. At the same time a research group of the US company Kosan Bioscience synthesized a DNA molecule from 32,000 roots, one of the proteins of E. Coli!

Finally in 2005, George Church assembled a DNA molecule consisting of up to 10 million roots. But with the wrong rate 10 times higher than your previous experiment! Summary: the genome complete with 4.7 million roots of Escherichia coli bacteria is considered to be within the reach of the researchers 'assembly'.

In December 2005, US magazine Wired listed a list of 20 biological facilities, including: DNA 2.0, Blue Heron, Codon Devices, Integrated DNA . Jeremy Minshull, leader of DNA 2.0 Company, came out For three years now, says: 'In 2003, the price of a base pair to produce DNA molecules was from 5-8 dollars. Now 1-3 USD '.

George Church predicted: 'The Codon Device Company I have established will be useful for a wide range of bio-chemical, chemical and medical engineering enterprises. We are equivalent to Microsoft or IBM in the field of biology '.

Minor genome for life

How many genes do life need to live to survive? This question has been asked by American biologist Craig Venter for many years. After participating in the largest genome decoding: humans, he turned to his original passion of pursuing the germ. Goal: determine the minimum number of genes a living organism needs to survive. This research topic itself was a big event.

Mycoplasma genitalium is a 'resident' of the planet that requires only 517 genes to ensure a creature: moving, eating, reproducing . However, all does not necessarily need to be sufficient and the researcher Just assemble about 250. From this basic gene stockpile, Craig Venter is ambitious to include new genes, allowing the production of hydrogen gas, or drawing CO2 from the greenhouse effect.

In fact, living is a very relative problem and has a close relationship with the surrounding environment. A minimal body, operating at 37 ° C most likely does not exist at 40 ° C, because it lacks some tool genes to adapt to environmental changes.

Therefore, believing that humans are identified with just one genome is to forget tens of thousands of other germs in the body, to supplement the essential needs for life. Dusko Ehrlich states: 'Each individual has thousands of different types of organisms in his body. And the number of germ cells in the body is 10 times more than our actual cells. If a person outside the universe observes us, they will be surprised to see the microbes living in the human body in a warm and intelligent way. '

Artificial cells

Without a computer, a computer program cannot run. So is life. Genetic programs can only run if there is a platform. This platform is a cell, surrounded by a membrane, that can interact with the outside.

In 2005, Albert Libchaber, a Frenchman working at Rockfeller University, New York, created proteins from within the cell, which then moved to the membrane to make a channel between inside and outside. Immediate effect. Cells live longer, by sucking food from the outside and discharging pollutants from the inside. It survived for a few days, compared to a few hours without a commercial channel.

As for the 'programming' so that the machine of life moves, we find it easier to write. The DNA molecule here consists of just under 10,000 base.

However, in order to create life, more factors are needed: enzymes to stimulate reactions; Amino acids for making base bricks, ribosomes for connecting amino acids . Although complicated, this formula has been well understood by researchers.

Depending on the views of each research group, people are targeting different applications. Mark Bedau, founder of ProtoLife Company, said: 'Artificial life forms can be used to treat environmental pollution. It eats what is for us is poison. It's possible to see cells as mini-factories, producing what humans can't do, like hydrogen. ' Mark Bedau asserted: 'When is an artificial cell born? Not far away! '. The optimism of this American researcher has begun to spread in Europe.

Create monsters?

Diverse life in nature is not chaotic. In contrast, all the germs, plants and animals in the universe are formed from basic bricks. That's about 20 foundation amino acids. So the researchers wondered: could it be possible to conceive of life with other 'bricks'? Peter Schultz, of the Scripps Research Institute in California, said: 'Although a code with 20 amino acids is enough to produce life, it may not be the best.'

Leading this discipline, in 2000 his team demonstrated: an organism like a microbe could get into the process of making amino acids, which is not its essence. Since then, this group has 'genetically encoded' more than 30 other amino acids. These are strange molecules that glow, or carry heavy atoms . unprecedented in the universe!

These monsters are still in the fetal stage. But the future benefits are huge. Researchers think of therapeutic molecular amino acids like polyethylenes glycol to improve the healing abilities of many drugs. Another group studied the creation of biological polymers from in vitro clustered proteins. There are groups that want to create germs that can remove soil to clean the environment, create hydrogen gas .

In theory, deploying genetic code not only allows to reach the source of life on Earth, but also helps to understand the form of life other than the universe. One thing is certain, if other life also exists in the universe, it will be the same language as us.

Parallel evolution of digital

It is not necessary to manipulate genes and molecules to understand the secret of life. With the advancement of computers, manipulating some data, like the environment, is able to understand the common dynamics of an evolutionary process, which is still very mysterious.

It's more 'mobile' than a laboratory biologist, because the modern power of computers can create several hundred generations of evolution in space after just a minute! And the results are not surprising to the researchers.

Chris Amadi, director of Life Digital Laboratory in Caltech, California, deployed Avida, a program with virtual creatures, called Avidiens. Microsoft has funded this lab.

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Creating life, is it dangerous? Integrated biology develops, and also brings social, environmental and ethical consequences.

In June 2005, a bioethics committee was established in the United States, involving philosophers and anthropologists. 32 years ago, in 1974, the Asilomar Committee was established, to regulate safety standards for gene transfer experiments, to monitor the level of danger of biotechnology to alert the world, before when it's too late .

DINH CONG THANH ( Science & Avenir 3-2006 )