<p style="text-align: justify;">Sugar beet line H7-1 was developed using recombinant DNA techniques to allow the use of glyphosate, the active ingredient in the herbicide Roundup&reg;, as a weed control option in sugar beet crops. The novel plants express an herbicide tolerant form of the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) derived from the common soil bacterium, <i>Agrobacterium tumefaciens</i> strain CP4. Glyphosate specifically binds to and inactivates EPSPS, which is involved in the synthesis of the aromatic amino acids, tyrosine, phenylalanine and tryptophan (shikimate biochemical pathway). EPSPS is present in all plants, bacteria, and fungi but not in animals, which must obtain these essential amino acids from their diet. Because the aromatic amino acid biosynthetic pathway is not present in mammalian, avian or aquatic life forms, glyphosate has little if any toxicity for these organisms (U.S. EPA, 1993; WHO, 1994; Williams et al. 2000). The EPSPS enzyme is normally present in food derived from plant and microbial sources.</p>
