Limitation of mitragynine biosynthesis in mitragyna speciosa (Roxb.) Korth. through tryptamine availability

Plant science

Structure of 2C-methyl-D-erythritol-2,4-cyclodiphosphate synthase involved in mevalonate-independent biosynthesis of isoprenoids

Isoprenoids are biosynthesized from isopentenyl diphosphate and the isomeric dimethylallyl diphosphate via the mevalonate pathway or a mevalonate-independent pathway that was identified during the last decade. The non-mevalonate pathway is present in many bacteria, some algae and in certain protozoa such as the malaria parasite Plasmodium falciparum and in the plastids of higher plants, but not in mammals and archaea. Therefore, these enzymes have been recognised as promising drug targets. We report the crystal structure of Escherichia coli 2C-methyl- D-erythritol-2,4-cyclodiphosphate synthase (IspF), which converts 4-diphosphocytidyl-2C-methyl-D-erythritol 2-phosphate into 2C-methyl-D-erythritol 2,4-cyclodiphosphate and CMP in a Mg-dependent reaction. The protein forms homotrimers that tightly bind one zinc ion per subunit at the active site, which helps to position the substrate for direct attack of the 2- phosphate group on the beta-phosphate. (C) 2002 Elsevier Science Ltd

J. Mol. Biol.

Isoprenoids are biosynthesized from isopentenyl diphosphate and the isomeric dimethylallyl diphosphate via the mevalonate pathway or a mevalonate-independent pathway that was identified during the last decade. The non-mevalonate pathway is present in many bacteria, some algae and in certain protozoa such as the malaria parasite Plasmodium falciparum and in the plastids of higher plants, but not in mammals and archaea. Therefore, these enzymes have been recognised as promising drug targets. We report the crystal structure of Escherichia coli 2C-methyl- D-erythritol-2,4-cyclodiphosphate synthase (IspF), which converts 4-diphosphocytidyl-2C-methyl-D-erythritol 2-phosphate into 2C-methyl-D-erythritol 2,4-cyclodiphosphate and CMP in a Mg-dependent reaction. The protein forms homotrimers that tightly bind one zinc ion per subunit at the active site, which helps to position the substrate for direct attack of the 2- phosphate group on the beta-phosphate. (C) 2002 Elsevier Science Ltd

Limitation of Mitragynine Biosynthesis in Mitragyna speciosa (Roxb.) Korth. through Tryptamine Availability

Plant science

Enzyme-assisted preparation of isotope-labeled 1-deoxy-D-xylulose 5-phosphate

Recombinant l-deoxy-D-xylulose 5-phosphate synthase of Bacillus subtilis was used for the preparation of isotope-labeled 1-deoxy-D-xylulose 5-phosphate using isotope-labeled glucose and/ or isotope-labeled pyruvate as starting materials. The simple one-pot methods described afford almost every conceivable isotopomer of l-deoxy-rt-xylulose 5-phosphate carrying C-13 Or C-14 from commercially available precursors with an overall yield around 50%