Soviet cosmonauts will carry a U.S. commercial project into space for the first time in a deal approved by the government, an attorney for the project said. Payload Systems Inc. of Wellesley, Mass., received a two-year license from the Commerce Department earlier this month to contract with the Soviet space agency to perform protein crystallization experiments aboard the Soviet space station Mir, the Washington attorney, Mark S. McConnell, said. "To my knowledge, it is the first time that the U.S. government has approved commercial activity in the Soviet space program," he said. The experiment will use the weightlessness of space to grow large, regular protein crystals for the development of new drugs. Since the explosion of the Challenger space shuttle, U.S. companies have had few alternatives for space projects.