Thomas Leustek is a professor of Plant Biology at Rutgers University in New Jersey and one of the writers of the study. He told VOA, "We improved the nutritional value of corn, the largest commodity crop grown on Earth." He added, "Most corn is used for animal feed, but it lacks methionine -- a key amino acid -- and we found an effective way to add it." The scientists genetically modified corn by adding the bacterium called E. coli into the genome of the corn plant