WASHINGTON, D.C. -- Scientists have created a living cell powered by man-made DNA. It's a bold step in the quest to build artificial organisms that might one day produce new fuels, clean polluted water or speed vaccine production. But is it truly an artificial life form? Its inventors call it the world's first synthetic cell, although this initial step is more a re-creation of existing life - changing one simple type of bacteria into another - than a built-from-scratch kind. Maryland genome-mapping pioneer J. Craig Venter said his team's project paves the way for the ultimate, harder goal: designing organisms that work differently than nature intended for a range of commercial uses.