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Haruo Seto - One of the best experts on this subject based on the ideXlab platform.
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fosmidomycin a specific inhibitor of 1 deoxy d Xylulose 5 phosphate reductoisomerase in the nonmevalonate pathway for terpenoid biosynthesis
Tetrahedron Letters, 1998Co-Authors: Tomohisa Kuzuyama, Tomohiro Shimizu, Shunji Takahashi, Haruo SetoAbstract:Fosmidomycin inhibited 1-deoxy-d-Xylulose 5-phosphate reductoisomerase pathway for terpenoid biosynthesis with IC50 of 8.2 nM.
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a 1 deoxy d Xylulose 5 phosphate reductoisomerase catalyzing the formation of 2 c methyl d erythritol 4 phosphate in an alternative nonmevalonate pathway for terpenoid biosynthesis
Proceedings of the National Academy of Sciences of the United States of America, 1998Co-Authors: Shunji Takahashi, Tomohisa Kuzuyama, Hiroyuki Watanabe, Haruo SetoAbstract:Several eubacteria including Esherichia coli use an alternative nonmevalonate pathway for the biosynthesis of isopentenyl diphosphate instead of the ubiquitous mevalonate pathway. In the alternative pathway, 2-C-methyl-d-erythritol or its 4-phosphate, which is proposed to be formed from 1-deoxy-d-Xylulose 5-phosphate via intramolecular rearrangement followed by reduction process, is one of the biosynthetic precursors of isopentenyl diphosphate. To clone the gene(s) responsible for synthesis of 2-C-methyl-d-erythritol 4-phosphate, we prepared and selected E. coli mutants with an obligatory requirement for 2-C-methylerythritol for growth and survival. All the DNA fragments that complemented the defect in synthesizing 2-C-methyl-d-erythritol 4-phosphate of these mutants contained the yaeM gene, which is located at 4.2 min on the chromosomal map of E. coli. The gene product showed significant homologies to hypothetical proteins with unknown functions present in Haemophilus influenzae, Synechocystis sp. PCC6803, Mycobacterium tuberculosis, Helicobacter pyroli, and Bacillus subtilis. The purified recombinant yaeM gene product was overexpressed in E. coli and found to catalyze the formation of 2-C-methyl-d-erythritol 4-phosphate from 1-deoxy-d-Xylulose 5-phosphate in the presence of NADPH. Replacement of NADPH with NADH decreased the reaction rate to about 1% of the original rate. The enzyme required Mn2+, Co2+, or Mg2+ as well. These data clearly show that the yaeM gene encodes an enzyme, designated 1-deoxy-d-Xylulose 5-phosphate reductoisomerase, that synthesizes 2-C-methyl-d-erythritol 4-phosphate from 1-deoxy-d-Xylulose 5-phosphate, in a single step by intramolecular rearrangement and reduction and that this gene is responsible for terpenoid biosynthesis in E. coli.
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direct formation of 2 c methyl d erythritol 4 phosphate from 1 deoxy d Xylulose 5 phosphate by 1 deoxy d Xylulose 5 phosphate reductoisomerase a new enzyme in the non mevalonate pathway to isopentenyl diphosphate
Tetrahedron Letters, 1998Co-Authors: Tomohisa Kuzuyama, Shunji Takahashi, Hidenori Watanabe, Haruo SetoAbstract:Abstract 1-Deoxy- d -Xylulose 5-phosphate is biotransformed to 2-C-methyl- d -erythritol 4-phosphate in a single step in the presence of NADPH by a new recombinant enzyme named 1-deoxy- d -Xylulose 5-phosphate reductoisomerase purified from Escherichia coli .
Michel Rohmer - One of the best experts on this subject based on the ideXlab platform.
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isoprenoid biosynthesis via the mep pathway synthesis of 3r 4s 3 4 dihydroxy 5 oxohexylphosphonic acid an isosteric analogue of 1 deoxy d Xylulose 5 phosphate the substrate of the 1 deoxy d Xylulose 5 phosphate reducto isomerase
Organic and Biomolecular Chemistry, 2003Co-Authors: Odile Meyer, Catherine Grosdemangebilliard, Denis Tritsch, Michel RohmerAbstract:(3R,4S)-3,4-Dihydroxy-5-oxohexylphosphonic acid, an isosteric analogue of 1-deoxy-D-Xylulose 5-phosphate (DXP), was obtained in enantiomerically pure form from (+)-2,3-O-benzylidene-D-threitol by a seven-step sequence. This phosphonate did not affect the growth of Escherichiacoli. It did not inhibit the 1-deoxy-D-Xylulose 5-phosphate reductoisomerase (DXR), but was converted by this enzyme into (3R,4R)-3,4,5-trihydroxy-3-methylpentylphosphonic acid, an isosteric analogue of 2-C-methyl-D-erythritol 4-phosphate. The enzyme was, however, less efficient with the methylene phosphonate analogue than with the natural substrate.
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elucidation of the 2 c methyl d erythritol 4 phosphate pathway for isoprenoid biosynthesis straightforward syntheses of enantiopure 1 deoxy d Xylulose from pentose derivatives
Tetrahedron Letters, 2001Co-Authors: Jeanfrancois Hoeffler, Catherine Grosdemangebilliard, Michel RohmerAbstract:Optically pure 1-deoxy-d-Xylulose, a key metabolite for feeding experiments in the methylerythritol phosphate pathway for isoprenoid biosynthesis, is conveniently synthesised from 1,2-O-isopropylidene-α-d-xylofuranose or from d-arabinose. This renders labelling with hydrogen isotopes possible.
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the discovery of a mevalonate independent pathway for isoprenoid biosynthesis in bacteria algae and higher plants
Natural Product Reports, 1999Co-Authors: Michel RohmerAbstract:1 Isoprenoid biosynthesis 1.1 The mevalonate route to isopentenyl diphosphate 1.2 Isoprenoid biosynthesis in higher plants: some contradictions with the mevalonate pathway 2 The discovery of the mevalonate-independent pathway 2.1 The origin of the discovery: the biosynthesis of bacterial hopanoids 2.2 The origin of the carbon atoms of isoprenic units in the mevalonate-independent pathway 2.3 d-Glyceraldehyde 3-phosphate and pyruvate as the first precursors of isopentenyl diphosphate 3 Towards the identification of intermediates and enzymes of the new pathway 3.1 1-Deoxy-d-Xylulose 5-phosphate and 1-deoxy-d-Xylulose 5-phosphate synthase 3.2 2-C-Methyl-d-erythritol 4-phosphate and 1-deoxy-d-Xylulose 5-phosphate reducto-isomerase 4 The distribution of the glyceraldehyde 3-phosphate/pyruvate pathway amongst prokaryotes 5 The distribution of the GAP/pyruvate pathway amongst phototrophic eukaryotes 5.1 Essential plant chloroplast isoprenoids and sterols from green algae 5.2 Isoprenoids from secondary metabolism 5.3 Intermediate exchanges between the mevalonate and the GAP/pyruvate pathways in plants 6 Conclusion 7 Acknowledgments 8 References
Tomohisa Kuzuyama - One of the best experts on this subject based on the ideXlab platform.
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fosmidomycin a specific inhibitor of 1 deoxy d Xylulose 5 phosphate reductoisomerase in the nonmevalonate pathway for terpenoid biosynthesis
Tetrahedron Letters, 1998Co-Authors: Tomohisa Kuzuyama, Tomohiro Shimizu, Shunji Takahashi, Haruo SetoAbstract:Fosmidomycin inhibited 1-deoxy-d-Xylulose 5-phosphate reductoisomerase pathway for terpenoid biosynthesis with IC50 of 8.2 nM.
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a 1 deoxy d Xylulose 5 phosphate reductoisomerase catalyzing the formation of 2 c methyl d erythritol 4 phosphate in an alternative nonmevalonate pathway for terpenoid biosynthesis
Proceedings of the National Academy of Sciences of the United States of America, 1998Co-Authors: Shunji Takahashi, Tomohisa Kuzuyama, Hiroyuki Watanabe, Haruo SetoAbstract:Several eubacteria including Esherichia coli use an alternative nonmevalonate pathway for the biosynthesis of isopentenyl diphosphate instead of the ubiquitous mevalonate pathway. In the alternative pathway, 2-C-methyl-d-erythritol or its 4-phosphate, which is proposed to be formed from 1-deoxy-d-Xylulose 5-phosphate via intramolecular rearrangement followed by reduction process, is one of the biosynthetic precursors of isopentenyl diphosphate. To clone the gene(s) responsible for synthesis of 2-C-methyl-d-erythritol 4-phosphate, we prepared and selected E. coli mutants with an obligatory requirement for 2-C-methylerythritol for growth and survival. All the DNA fragments that complemented the defect in synthesizing 2-C-methyl-d-erythritol 4-phosphate of these mutants contained the yaeM gene, which is located at 4.2 min on the chromosomal map of E. coli. The gene product showed significant homologies to hypothetical proteins with unknown functions present in Haemophilus influenzae, Synechocystis sp. PCC6803, Mycobacterium tuberculosis, Helicobacter pyroli, and Bacillus subtilis. The purified recombinant yaeM gene product was overexpressed in E. coli and found to catalyze the formation of 2-C-methyl-d-erythritol 4-phosphate from 1-deoxy-d-Xylulose 5-phosphate in the presence of NADPH. Replacement of NADPH with NADH decreased the reaction rate to about 1% of the original rate. The enzyme required Mn2+, Co2+, or Mg2+ as well. These data clearly show that the yaeM gene encodes an enzyme, designated 1-deoxy-d-Xylulose 5-phosphate reductoisomerase, that synthesizes 2-C-methyl-d-erythritol 4-phosphate from 1-deoxy-d-Xylulose 5-phosphate, in a single step by intramolecular rearrangement and reduction and that this gene is responsible for terpenoid biosynthesis in E. coli.
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direct formation of 2 c methyl d erythritol 4 phosphate from 1 deoxy d Xylulose 5 phosphate by 1 deoxy d Xylulose 5 phosphate reductoisomerase a new enzyme in the non mevalonate pathway to isopentenyl diphosphate
Tetrahedron Letters, 1998Co-Authors: Tomohisa Kuzuyama, Shunji Takahashi, Hidenori Watanabe, Haruo SetoAbstract:Abstract 1-Deoxy- d -Xylulose 5-phosphate is biotransformed to 2-C-methyl- d -erythritol 4-phosphate in a single step in the presence of NADPH by a new recombinant enzyme named 1-deoxy- d -Xylulose 5-phosphate reductoisomerase purified from Escherichia coli .
Merja Penttilä - One of the best experts on this subject based on the ideXlab platform.
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metabolic engineering of saccharomyces cerevisiae for conversion of d glucose to xylitol and other five carbon sugars and sugar alcohols
Applied and Environmental Microbiology, 2007Co-Authors: Mervi Toivari, Andrei Miasnikov, Peter Richard, Laura Ruohonen, Merja PenttiläAbstract:Recombinant Saccharomyces cerevisiae strains that produce the sugar alcohols xylitol and ribitol and the pentose sugar d-ribose from d-glucose in a single fermentation step are described. A transketolase-deficient S. cerevisiae strain accumulated d-Xylulose 5-phosphate intracellularly and released ribitol and pentose sugars (d-ribose, d-ribulose, and d-Xylulose) into the growth medium. Expression of the xylitol dehydrogenase-encoding gene XYL2 of Pichia stipitis in the transketolase-deficient strain resulted in an 8.5-fold enhancement of the total amount of the excreted sugar alcohols ribitol and xylitol. The additional introduction of the 2-deoxy-glucose 6-phosphate phosphatase-encoding gene DOG1 into the transketolase-deficient strain expressing the XYL2 gene resulted in a further 1.6-fold increase in ribitol production. Finally, deletion of the endogenous xylulokinase-encoding gene XKS1 was necessary to increase the amount of xylitol to 50% of the 5-carbon sugar alcohols excreted.
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a novel nadh linked l Xylulose reductase in the l arabinose catabolic pathway of yeast
Journal of Biological Chemistry, 2004Co-Authors: Ritva Verho, John Londesborough, Merja Penttilä, Mikko Putkonen, Peter RichardAbstract:Abstract An NADH-dependent l-Xylulose reductase and the corresponding gene were identified from the yeast Ambrosiozyma monospora. The enzyme is part of the yeast pathway for l-arabinose catabolism. A fungal pathway for l-arabinose utilization has been described previously for molds. In this pathway l-arabinose is sequentially converted to l-arabinitol, l-Xylulose, xylitol, and d-Xylulose and enters the pentose phosphate pathway as d-Xylulose 5-phosphate. In molds the reductions are NADPH-linked, and the oxidations are NAD+-linked. Here we show that in A. monospora the pathway is similar, i.e. it has the same two reduction and two oxidation reactions, but the reduction by l-Xylulose reductase is not performed by a strictly NADPH-dependent enzyme as in molds but by a strictly NADH-dependent enzyme. The ALX1 gene encoding the NADH-dependent l-Xylulose reductase is strongly expressed during growth on l-arabinose as shown by Northern analysis. The gene was functionally overexpressed in Saccharomyces cerevisiae and the purified His-tagged protein characterized. The reversible enzyme converts l-Xylulose to xylitol. It also converts d-ribulose to d-arabinitol but has no activity with l-arabinitol or adonitol, i.e. it is specific for sugar alcohols where, in a Fischer projection, the hydroxyl group of the C-2 is in the l-configuration and the hydroxyl group of C-3 is in the d-configuration. It also has no activity with C-6 sugars or sugar alcohols. The Km values for l-Xylulose and d-ribulose are 9.6 and 4.7 mm, respectively. To our knowledge this is the first report of an NADH-linked l-Xylulose reductase.
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the missing link in the fungal l arabinose catabolic pathway identification of the l Xylulose reductase gene
Biochemistry, 2002Co-Authors: Peter Richard, John Londesborough, Mikko Putkonen, Ritva Vaananen, Merja PenttiläAbstract:The fungal l-arabinose pathway consists of five enzymes, aldose reductase, l-arabinitol 4-dehydrogenase, l-Xylulose reductase, xylitol dehydrogenase, and xylulokinase. All the genes encoding the enzymes of this pathway are known except for that of l-Xylulose reductase (EC 1.1.1.10). We identified a gene encoding this enzyme from the filamentous fungus Trichoderma reesei (Hypocrea jecorina). The gene was named lxr1. It was overexpressed in the yeast Saccharomyces cerevisiae, and the enzyme activity was confirmed in a yeast cell extract. Overexpression of all enzymes of the l-arabinose pathway in S. cerevisiae led to growth of S. cerevisiae on l-arabinose; i.e., we could show that the pathway is active in a heterologous host. The lxr1 gene encoded a protein with 266 amino acids and a calculated molecular mass of 28 428 Da. The LXRI protein is an NADPH-specific reductase. It has activity with l-Xylulose, d-Xylulose, d-fructose, and l-sorbose. The highest affinity is toward l-Xylulose (Km = 16 mM). In the rev...
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the role of xylulokinase in saccharomyces cerevisiae Xylulose catabolism
Fems Microbiology Letters, 2000Co-Authors: Peter Richard, Mervi Toivari, Merja PenttiläAbstract:Many yeast species have growth rates on D-Xylulose of 25^130% of those on glucose, but for Saccharomyces cerevisiae this ratio is only about 6%. The xylulokinase reaction has been proposed to be the rate-limiting step in the D-Xylulose fermentation with S. cerevisiae. Overexpression of xylulokinase encoding XKS1 stimulated growth on D-Xylulose in a S. cerevisiae strain to about 20% of the growth rate on glucose and deletion of the gene prevented growth on D-Xylulose and D-Xylulose metabolism. We have partially purified the xylulokinase and characterised its kinetic properties. It is reversible and will also accept D-ribulose as a substrate. fl 2000 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.
Barbel Hahnhagerdal - One of the best experts on this subject based on the ideXlab platform.
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the non oxidative pentose phosphate pathway controls the fermentation rate of Xylulose but not of xylose in saccharomyces cerevisiae tmb3001
Fems Yeast Research, 2002Co-Authors: Björn Johansson, Barbel HahnhagerdalAbstract:Saccharomyces cerevisiae is able to ferment xylose, when engineered with the enzymes xylose reductase (XYL1) and xylitol dehydrogenase (XYL2). However, xylose fermentation is one to two orders of magnitude slower than glucose fermentation. S. cerevisiae has been proposed to have an insufficient capacity of the non-oxidative pentose phosphate pathway (PPP) for rapid xylose fermentation. Strains overproducing the non-oxidative PPP enzymes ribulose 5-phosphate epimerase (EC 5.1.3.1), ribose 5-phosphate ketol isomerase (EC 5.3.1.6), transaldolase (EC 2.2.1.2) and transketolase (EC 2.2.1.1), as well as all four enzymes simultaneously, were compared with respect to xylose and Xylulose fermentation with their xylose-fermenting predecessor S. cerevisiae TMB3001, expressing XYL1, XYL2 and only overexpressing XKS1 (xylulokinase). The level of overproduction in S. cerevisiae TMB3026, overproducing all four non-oxidative PPP enzymes, ranged between 4 and 23 times the level in TMB001. Overproduction of the non-oxidative PPP enzymes did not influence the xylose fermentation rate in either batch cultures of 50 g l(-1) xylose or chemostat cultures of 20 g l(-1) glucose and 20 g l(-1) xylose. The low specific growth rate on xylose was also unaffected. The results suggest that neither of the non-oxidative PPP enzymes has any significant control of the xylose fermentation rate in S. cerevisiae TM133001. However, the specific growth rate on Xylulose increased from 0.02-0.03 for TMB3001 to 0.12 for the strain overproducing only transaldolase (TAL1) and to 0.23 for TMB3026, suggesting that overproducing all four enzymes has a synergistic effect. TMB3026 consumed Xylulose about two times faster than TMB30001 in batch culture of 50 g l(-1) Xylulose. The results indicate that growth on Xylulose and the Xylulose fermentation rate are partly controlled by the non-oxidative PPP, whereas control of the xylose fermentation rate is situated upstream of xylulokinase, in xylose transport, in xylose reductase, and/or in the xylitol dehydrogenase. (C) 2002 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.
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Xylulose fermentation by mutant and wild type strains of zygosaccharomyces and saccharomyces cerevisiae
Applied Microbiology and Biotechnology, 2000Co-Authors: A Eliasson, Björn Johansson, Eckhard Boles, M Osterberg, Johan M Thevelein, I Spencermartins, H Juhnke, Barbel HahnhagerdalAbstract:Anaerobic Xylulose fermentation was compared in strains of Zygosaccharomyces and Saccharomyces cerevisiae, mutants and wild-type strains to identify host-strain background and genetic modifications beneficial to xylose fermentation. Overexpression of the gene (XKS1) for the pentose phosphate pathway (PPP) enzyme xylulokinase (XK) increased the ethanol yield by almost 85% and resulted in ethanol yields [0.61 C-mmol (C-mmol consumed Xylulose)−1] that were close to the theoretical yield [0.67 C-mmol (C-mmol consumed Xylulose)−1]. Likewise, deletion of gluconate 6-phosphate dehydrogenase (gnd1Δ) in the PPP and deletion of trehalose 6-phosphate synthase (tps1Δ) together with trehalose 6-phosphate phosphatase (tps2Δ) increased the ethanol yield by 30% and 20%, respectively. Strains deleted in the promoter of the phosphoglucose isomerase gene (PGI1) – resulting in reduced enzyme activities – increased the ethanol yield by 15%. Deletion of ribulose 5-phosphate (rpe1Δ) in the PPP abolished ethanol formation completely. Among non-transformed and parental strains S. cerevisiae ENY. WA-1A exhibited the highest ethanol yield, 0.47 C-mmol (C-mmol consumed Xylulose)−1. Other non-transformed strains produced mainly arabinitol or xylitol from Xylulose under anaerobic conditions. Contrary to previous reports S. cerevisiae T23D and CBS 8066 were not isogenic with respect to pentose metabolism. Whereas, CBS 8066 has been reported to have a high ethanol yield on Xylulose, 0.46 C-mmol (C-mmol consumed Xylulose)−1 (Yu et al. 1995), T23D only formed ethanol with a yield of 0.24 C-mmol (C-mmol consumed Xylulose)−1. Strains producing arabinitol did not produce xylitol and vice versa. However, overexpression of XKS1 shifted polyol formation from xylitol to arabinitol.
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effects of increased transaldolase activity on d Xylulose and d glucose metabolism in saccharomyces cerevisiae cell extracts
Applied and Environmental Microbiology, 1991Co-Authors: Thomas Senac, Barbel HahnhagerdalAbstract:In vitro metabolism of D-Xylulose and D-glucose in extracts obtained from D-glucose- and D-Xylulose-fermenting Saccharomyces cerevisiae cells was investigated with 10- and 100-fold-increased activity of the enzyme transaldolase (EC 2.2.1.2). The rate of sugar consumption was the same in most cases, whereas the rate of ethanol formation decreased with increased levels of transaldolase. The formation of glycerol, pentitols, and acetic acid was not dependent on added transaldolase but was dependent on the sugar used as the growth substrate and on the sugar used in the in vitro metabolism experiments. The carbon balance showed that the dissimilated carbon could not be accounted for in products when transaldolase was added. The concentration of D-fructose-1,6.-diphosphate in the extracts was not influenced by added transaldolase but was higher with D-Xylulose than with D-glucose. Levels of pyruvate, comparable with the two substrates, decreased with increasing levels of transaldolase. Exogenously added transaldolase decreased D-sedoheptulose-7-phosphate levels when D-Xylulose was the substrate. The results are discussed in relation to the dissimilation of carbon through the upper part of glycolysis and the pentose phosphate pathway.