Just like factory workers, molecules shepherd products to the finish of the production line:-"They saw salt bridges form and the enzyme grab helices and pull them apart. The growing chain of fatty acids also loops back into a pocket in the carrier molecule. "We call it the marsupial protein," Burkart says. "It protects its young." That is, until it's time for the product to go. "We thought this tiny protein was just a transporter," Tsai said. "But when it ejects its cargo, it works like a piston. We see a helical collapse forcing the fatty acid out.'"- Read more at: http://phys.org/news/2013-12-biosynthesis-captured-motion.html#jCp