Site-directed mutagenesis (SDM) as a powerful technique was used to change two important and conserved amino acids in 5-enolpyruvylshikimate 3- phosphate synthase (EPSPS) gene of E. coli. The mutations changed glycine 96 to alanine and alanine 183 to threonine. These two amino acids are very important for intraction of the wide spectrum herbicide, glyphosate, to EPSP synthase enzymes. By design...

The levels of resistance to glyphosate 13 barnyard grass ( Echinochloa crus-galli ) populations harvested across different agriculture areas in the Southern Iberian Peninsula were determined greenhouse and laboratory experiments. Shikimate accumulation fast screening separated regarding glyphosate: susceptible (S) E2, E3, E4, E6 resistant (R) E1, E5, E7, E8, E9, E10, E11, E12, E13. However, fac...

The prime molecular target of glyphosate (N-[phosphonomethyl]glycine), a potent herbicidal and antimicrobial agent, is known to be the shikimate-pathway enzyme, 5-enol-pyruvylshikimate-3-phosphate synthase. Inhibition by glyphosate of an earlier pathway enzyme that is located in the cytosol of higher plants, 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase (DS-Co), has raised the possibilit...

Considerable enzymological diversity underlies the capacity for biosynthesis of aromatic amino acids in nature. For this biochemical pathway, higher plants as a group exhibit a uniform pattern of pathway steps, compartmentation, and catalytic, physical and allosteric properties of enzymes. This biochemical pattern of higher plants contains a collection of features which are completely different...

It is generally claimed that glyphosate kills undesired plants by affecting the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme, disturbing the shikimate pathway. However, the mechanisms leading to plant death may also be related to secondary or indirect effects of glyphosate on plant physiology. Moreover, some plants can metabolize glyphosate to aminomethylphosphonic acid (AMPA) or ...

5-enolPyruvylshikimate-3-phosphate synthase (EPSP synthase; 3-phosphoshikimate 1-carboxyvinyl-transferase; EC 2.5.1.19) is a chloroplast-localized enzyme of the shikimate pathway in plants. This enzyme is the target for the nonselective herbicide glyphosate (N-phosphonomethylglycine). We have previously isolated a full-length cDNA clone of EPSP synthase from Petunia hybrida. DNA sequence analys...

Sorghum bicolor stems and shoots were observed to phosphorylate exogenously supplied shikimate, forming a product which could not be distinguished from shikimate 3-phosphate by anion exchange and thin layer chromatography. Upon treatment with phosphatase, this product gave rise to a compound which co-chromatographed with shikimate.Shikimate kinase from stems was separated from phosphatase and A...

3-Hexulose phosphate synthase and phospho-3-hexuloisomerase were purified 40- and 150-fold respectively from methane-grown Methylococcus capsulatus. The molecular weights of the enzymes were approximately 310000 and 67000 respectively, as determined by gel filtration. Dissociation of 3-hexulose phosphate synthase into subunits of molecular weight approx. 49000 under conditions of low pH or low ...

The enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) catalyzes the penultimate step of the shikimate pathway, and is the target of the broad-spectrum herbicide glyphosate. Kinetic analysis of the cloned EPSPS from Staphylococcus aureus revealed that this enzyme exerts a high tolerance to glyphosate, while maintaining a high affinity for its substrate phosphoenolpyruvate. Enzymatic act...

The engineering of transgenic canola (Brassica napus L. ) to make tolerance to the broad-spectrum herbicide, glyphosate, is one of the most effective approaches for weed management. Glyphosate inhibits the enzyme EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) enzyme which functions in the shikimate pathway and has a key role in biosynthesis of aromatic amino acids required for survival of ...