Chorismate mutase, aromatic amino acid synthesis

Figure 4. Enzymes of Rhizobium (a) and Lemna (b) proposed as sites of glyphosate inhibition of aromatic amino acid synthesis. Abbreviations CM, chorismate mutase PDH, prephenate dehydrogenase and PD, prephenate dehydratase.

Fig. 6. Regulation of the synthesis of aromatic amino acids in plants. Each of the sequential arrows represents the enzyme catalyzed steps detected in Figs. 2, 3 and 4. Bold lines indicate inhibition of chorismate mutase by phenylalanine and tyrosine in addition to anthranilate synthase inhibition by tryptophan. The dashed arrow symbolizes the ability of tryptophan to both activate chorismate mutase and antagonize inhibition of this enzyme by either phenylalanine or tyrosine.

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