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For biologists, roentgen ray crystallizationlography has always been a tricky technology. Harder than getting a good shine was growing large crystals of biological molecules-a task thats been comp atomic number 18d to building regular structures from writhing bits of Jello. Today, synchrotron light from facilities such as Berkeley Labs Advanced Light Source whitethorn make it possible to use protein crystals as small as 50 microns (50 millionths of a meter) in length. The crystals themselves may also become easier to grow, thanks to a unique robotic system designed and strengthened by Joseph Jaklevic, head of technology Sciences, and his colleagues in the Engineering Divisions Bioinstrumentation Department. "The idea for a high- throughput combinatorial approach to crystal growth came from Peter Schultz," says Jaklevic. "The basic idea is that, instead of having to plod through all the hundreds of ways you might get a protein to crystallize, you more or less try em all at once." Schultz pi superstarered combinatorial methods as a member of the Labs Materials Sciences Division he recently became head of the Novartis Institute for practicable Genomics in La Jolla, California. He and his colleague Raymond Stevens of the Labs Physical Biosciences Division sawing machine the combinatorial approach as a natural ancestor to the scrap of growing protein crystals. Thats because "biologists really have no idea what the best conditions are for growing crystals of a new protein," says Derek Yegian, a member of the team that built the new robotic system. "Different proteins precipitate out of solution and grow at variant rates-or dont grow at all-depending on the solutions acidity, temperature, concentrations of salts, and lots of other variables. " The sophisticated robot above, designed and built by Joe Jaklevic and his colleagues in the Engineering Divisions Bioinstrumentation Department, drive out automatically grow crystals o f a novel protein by screening 480 different growth solutions at once. Only the very purest proteins will crystallize, and pure protein is high-ticket(prenominal) even common commercial proteins thunder mug cost hundreds of dollars a gram. often hundreds of combinations of variables must be tried before a novel protein can be crystallized from solution. Most trial solutions are prepared by hand at the rate of about 30 an hour, typically requiring one to 10 microliters of pure protein for 50 to 100 "coarse-screening" trials whether a particular solution yields a crystal is apparent only days or weeks later. " manual methods are slow and error-prone," says Yegian, and although some steps have been automated inwardly the past few years, "commercial robots are not much better.