<p style="text-align: justify;">MON 88913 (Roundup Ready&reg; Flex) cotton was developed to allow the use of glyphosate, the active ingredient in the herbicide Roundup&reg;, as a weed control option in cotton production. This genetically engineered cotton variety contains a glyphosate-tolerant form of the plant enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), isolated from the soil bacterium <i>Agrobacterium tumefacien</i> strain CP4, hereafter termed CP4 EPSPS. Compared to previously approved glyphosate tolerant lines of cotton, which will tolerate glyphosate applications only to the fifth true leaf stage, MON 88913 was developed to tolerate glyphosate applications beyond the fifth true leaf stage.</p>

<p style="text-align: justify;">The EPSPS enzyme is part of the shikimate pathway that is involved in the production of aromatic amino acids and other aromatic compounds in plants (Steinrucken &amp; Amrhein, 1980). When conventional plants are treated with glyphosate, the herbicide binds to EPSPS, thereby preventing the synthesis of aromatic amino acids needed for plant growth. The CP4 EPSPS enzyme in MON 88913 cotton has a reduced affinity for glyphosate; its enzymatic activity is therefore not hindered by the herbicide.</p>

<p style="text-align: justify;">EPSPS is present in all plants, bacteria, fungi, but not in animals, which do not synthesize their own aromatic amino acids. 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>

<p style="text-align: justify;">MON 88913 cotton was developed by introducing two CP4 EPSPS coding sequences into the cotton variety &lsquo;Coker 312&rsquo; using <i>Agrobacterium</i>-mediated transformation.</p>
