The cp4 epsps gene, which encodes a glyphosate-tolerant form of the enzyme 5- enolpyruvlyshikimate-3-phosphate synthase (EPSPS), was isolated from the bacterium Agrobacterium tumefaciens strain CP4 and inserted into the maize genome using the bioballistic method (acceleration of particles). The mode of action of glyphosate, causing plant death, is due to its ability to block the activity of the target enzyme (EPSPS) belonging to the biosynthetic pathway of the aromatic amino acids tyrosine, phenylalanine and tryptophan. Thus, plant cells that express the CP4 EPSPS protein continue to produce essential aromatic amino acids when metabolism even in the presence of glyphosate. The CP4 EPSPS protein is one of many EPSPS proteins found in nature, which are produced by plants, bacteria and fungi, but not by animals, since they do not have the metabolic pathway for their synthesis. Therefore, different versions of the EPSPS protein are normally present in all foods derived from plants and microorganisms. The gene donor organism, A. tumefaciens strain CP4 is a bacterium commonly found in soil that causes galls on susceptible plants and there is no scientific evidence to indicate that it can cause adverse effects in humans or in animals. NK603 corn was produced by genetically transforming the LH82XB73 corn line, using a 6706 base pair (bp) linearized DNA fragment that contained two adjacent cassettes of the cp4 epsps gene for expression of the CP4 EPSPS protein. Each of the cassettes, called the proximal (closest to the 5' end) and distal (closest to the 5' end) cassette 3' end), contained a single copy of the cp4 epsps gene and its regulatory sequences.