EPSPS genes

More recently, the nucleotide sequences of tomato and Arabid-opsis EPSPS genes have been determined (42, 43). It is interesting to note that the mature plant EPSPS shows a high degree of conservation at the amino acid level (>85%). Comparison of the plant EPSPS sequences with bacterial and fungal EPSPS sequences reveals that there is a 38% identity between plant and fungal enzymes while between the bacterial and plant enzymes, there is a 54% identity. The transit peptides of the plant enzymes are not conserved to a similar extent between the Arabidopsis and petunia transit peptides, 23% identity is observed. The same pattern of... 

The E. coli mutant EPSPS gene was engineered into a plant expression vector (pMON8078) and used for transformation of tobacco leaf discs. In this construct, the mutant EPSPS gene was driven by the CaMV 35S promoter and the 3 -polyadenylation signal was derived from the nopaline synthase gene. 

EPSPS specific activites of calli transformed with EPSPS genes with and without chloroplast transit sequences... 

More recently, the petunia EPSPS gene has been demonstrated to confer Roundup tolerance in transgenic tomato plants. The transgenic tomato plants were tested under field conditions for their productivity and vigor. No significant differences were observed in crop productivity between transgenic and control tomato plants. This demonstrates that introduction and expression of genes into plants does not affect crop yield. 

Best known as genes conveying new properties are the EPSPS gene from the plant Petunia hybrida, which codes for tolerance to the herbicide Roundup Ready [this is found in the Roundup Ready soybean (RRS)], and the cry genes from Bacillus... 

Song, N. W. Kim, H. H. Methods and FRET probes for detection of herbicide-resistant EPSPS gene-containing soybean plants using laser induced fluorescence. PCT Int. Appl. WO 2006121277, 2006 Chem. Abstr. 2006, 145, 501856. 

Watrud, L.S., Lee, E.H., Fairbrother, A., Burdick, C., Reichman, J.R., Bollman, M., Storm, M., King, G. and Van de Water, RK. (2004). Evidence for landscape-level, pollen-mediated gene flow from genetically modified creeping bentgrass with CP4 EPSPS as a marker , Proc. Natl. Acad. Sci., 101, 14533-14538. 

Watrud, L. S. et. al. 2004. Evidence for landscape-level, pollen-mediated gene flow from genetically modified creeping bentgrass with CP4 EPSPS as a marker. Proceedings of the National Academy of Sciences USA 101 14533-14538. 

Since aromatic amino acid biosynthesis occurs in the chloroplast of plants, and the petunia EPSPS was demonstrated to contain the information for its translocation to the chloroplast, it was of interest to determine if delivery of the bacterial mutant enzyme to chloroplast of transgenic plants affected the level of tolerance to Roundup . A hybrid gene was synthesized containing... 

To illustrate engineered resistance, we may use some data from Amaud et al. (1998), summarized in Table 9.5. A gene from Salmonella (aroA) encodes a glyphosate-tolerant EPSP synthase. EPSP synthase is the target enzyme for... 

EPSPS a single copy of the gene coding for glyphosate tolerance CP4 5-enolpyruvylshikimate-3-phosphate synthase (CP4 EPSPS) bom Agrobacterium sp. strain CP4. 

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