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cnrs I international w 26 | Focus magazine sorting out molecul es Simulating the complexity of nature is a key challenge for Jean-François Lutz, from Strasbourg’s ICS,1 who is developing a technique to control the construction of a polymer. “Our goal is to monitor the order of the molecules that make it up, in the same way as nature does for the base sequences of DNA,” the scientist explains. When growing polystyrene macromolecules, the researchers insert specific molecules, called maleimides, between the links of the polymer chain. These maleimides can carry various chemical substituents, and thus different types of information. The laboratory has developed about 30 of them so far—like letters in a molecular alphabet. “For the moment, we are able to incorporate about 10 of them into each chain,” Lutz reports. At this stage, the sequences created still have flaws, but the w As an art buff in the making, a robot called Berenson spent a week at the Quai Branly Museum in Paris in April 2012. “A visitor would tell Berenson whether or not he liked the statues on display. The robot thus learned the person’s preferences, especially in terms of shapes,” explains Philippe Gaussier of ET IS1 who, with anthropologist Denis Vidal,2 possibilities are enormous, in particular in the field of data storage. “The monomer unit of a polymer could represent data bits on the scale of the angstrom, which is 10 to 1000 times smaller than current nanotechnology.” Another variant of this approach is the inclusion in these new polymers of components with specific properties: hydrophobic, hydrophilic, negatively or positively charged, etc. This could pave the way towards monomolecular machines capable of catalyzing certain reactions, like virtual enzymes. “But we’ll have to be patient,” Lutz cautions, “it could be another 10 to 20 years before these applications come to fruition.” 01. Institut Charles Sadron (CNRS ). Contact i nformation: Jean-François Lutz, jflutz@unistra.fr co-heads this project.3 “Then, according to the esthetic preference just acquired, the robot would smile or frown when looking at new statues.” 01. E quipe traitement de l’information et système (CNRS / UCP / ENSEA ). 02. Institut de recherche pour le développement. 03. T he project is funded by Partnering 3.0 and Labex Patrima. Contact i nformation: Philippe Gaussier, gaussier@ensea.fr butterfl y q T he antennae of the mulberry silk moth (left) are made up of millimeterthin bristles covered with sensilla that are directly connected to sensory What if muscle tissue could be imitated in the finest detail? This is one of the challenges taken on a few years ago by researchers from Strasbourg’s chemistry institute,1 who have been working on the development of devices called molecular machines. “In 2000, we synthesized a machine that imitates the way actin filaments slide past myosin2 filaments in muscles,” explains researcher Jean-Pierre Sauvage, a pioneer in this field. “The resulting system contracts or extends in response to chemical reactions.” Today, the laboratory is pursuing this avenue by developing a technique for assembling a  polymer  based on an optimized initial molecular motor. “Such systems could eventually be used to develop electro-, photo-, or chemo-mechanical devices,” he adds. “For the moment though, we are just trying to reproduce muscle function—it would be premature to talk about ‘bionics’ this early in the process.” Machines and motors of another type are also on the drawing board, based on “mimicking chaperone proteins, whose cavities accommodate enzymes that have undergone deformation and are no longer active,” Sauvage explains. “The chaperone protein ‘massages’ the enzyme back to its original form. Taking this mechanism as a model, we have created a molecular compressor that can capture a molecule and modify its shape.” 01. Institut de chimie de Strasbourg (CNRS / Université de Strasbourg). 02. A ctin and myosin are the two main components of muscle fibers. Muscular contraction is the result of their dynamic interaction. Contact i nformation: Jean-Pierre Sauvage, jpsauvage@unistra.fr motors wi th muscl e polymer. A macromolecule formed through the repetition of basic units. q A synthetic molecular muscle capable of contraction and extension. © photos : f. schnell /ns3e/isl © c. zannettacci/musée du quai branly ©j.-p. sauvage/cnrs photothèque


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