Synthesis of Methylerythritol Phosphate Analogues and Their Evaluation as Alternate Substrates for IspDF and IspE from <i>Agrobacterium tumefaciens</i>

The methylerythritol phosphate biosynthetic pathway, found in most Bacteria, some parasitic protists, and plant chloroplasts, converts d-glyceraldehyde phosphate and pyruvate to isopentenyl diphosphate (<b>IPP</b>) and dimethylallyl diphosphate (<b>DMAPP</b>), where it intersects with the mevalonate pathway found in some Bacteria, Archaea, and Eukarya, including the cytosol of plants. d-3-Methylerythritol-4-phosphate (<b>MEP</b>), the first pathway-specific intermediate in the pathway, is converted to <b>IPP</b> and <b>DMAPP</b> by the consecutive action of the IspD-H proteins. We synthesized five d-<b>MEP</b> analoguesd-erythritol-4-phosphate (<b>EP</b>), d-3-methylthrietol-4-phosphate (<b>MTP</b>), d-3-ethylerythritol-4-phosphate (<b>EEP</b>), d-1-amino-3-methylerythritol-4-phosphate (<b>NMEP</b>), and d-3-methylerythritol-4-thiolophosphate (<b>MESP</b>)and studied their ability to function as alternative substrates for the reactions catalyzed by the IspDF fusion and IspE proteins from <i>Agrobacterium tumefaciens</i>, which covert <b>MEP</b> to the corresponding eight-membered cyclic diphosphate. All of the analogues, except <b>MTP</b>, and their products were substrates for the three consecutive enzymes