- Design of a synthetic enzyme cascade for the: In vitro fixation of a C1carbon source to a functional C4sugar
-
Realizing a sustainable future requires intensifying the waste stream conversion, such as converting the greenhouse gas carbon dioxide into value-added products. In this paper, we focus on utilizing formaldehyde as a C1 carbon source for enzymatic C-C bond formation. Formaldehyde can be sustainably derived from other C1 feedstocks, and in this work, we designed a synthetic enzyme cascade for producing the functional C4 sugar erythrulose. This involved tailoring the enzyme formolase, which was optimized for fusing formaldehyde, from a three-carbon producer (dihydroxyacetone) to sets of variants with enhanced two-carbon (glycolaldehyde) or four-carbon (erythrulose) activity. To achieve this, a high-throughput combinatorial screening was developed, and every single variant was evaluated in terms of glycolaldehyde, dihydroxyacetone and erythrulose activity. By applying the two most promising variants in an enzyme cascade, we were able to show for the first time production of ERY starting from a C1 carbon source. In addition, we demonstrated that one of our tailored formolase variants was able to convert 25.0 g L-1 glycolaldehyde to 24.6 g L-1 erythrulose (98% theoretical yield) in a fully atom-economic biocatalytic process. This represents the highest achieved in vitro concentration of erythrulose to date.
- Güner, Samed,Pick, André,Sieber, Volker,Wegat, Vanessa
-
supporting information
p. 6583 - 6590
(2021/09/10)
-
- PROCESSES FOR PREPARING C-4 SUGARS AND KETOSE SUGARS
-
Various processes for preparing C4 aldoses and/or ketones thereof are described. Various processes are described for preparing C4 aldoses and/or ketones thereof from feed compositions comprising glycolaldehyde. Also, various processes for preparing useful downstream products and intermediates, such as erythritol and erythronic acid, from the C4 aldoses and/or ketones thereof are described.
- -
-
Page/Page column 37-39
(2021/11/20)
-
- Efficient Production of Biomass-Derived C4 Chiral Synthons in Aqueous Solution
-
Carbohydrates are expected to replace petroleum and to become the base of industrial chemistry. Chirality is one particular area in which carbohydrates have a special potential advantage over petroleum resources. Herein, we report a catalytic approach for the direct production of d-tetroses [i.e., d-(?)-erythrose and d-(+)-erythrulose] from d-hexoses through a fast retro-aldol process at 190 °C that achieves a yield of 46 % and completely retains the chiral centers in the final chiral synthon. The d-tetrose products were further converted into their derivatives, thereby accomplishing transfer of chirality from natural chiral hexoses to high-value-added chiral chemicals. Our results also suggest that the product distribution for the conversion of d-hexoses was determined by their isomerization and epimerization trends that competed with their corresponding retro-aldol condensation processes.
- Lin, Shaoying,Guo, Xiao,Qin, Kai,Feng, Lei,Zhang, Yahong,Tang, Yi
-
p. 4179 - 4184
(2017/12/02)
-
- Shape-selective Valorization of Biomass-derived Glycolaldehyde using Tin-containing Zeolites
-
A highly selective self-condensation of glycolaldehyde to different C4 molecules has been achieved using Lewis acidic stannosilicate catalysts in water at moderate temperatures (40–100 °C). The medium-sized zeolite pores (10-membered ring framework) in Sn-MFI facilitate the formation of tetrose sugars while hindering consecutive aldol reactions leading to hexose sugars. High yields of tetrose sugars (74 %) with minor amounts of vinyl glycolic acid (VGA), an α-hydroxyacid, are obtained using Sn-MFI with selectivities towards C4 products reaching 97 %. Tin catalysts having large pores or no pore structure (Sn-Beta, Sn-MCM-41, Sn-SBA-15, tin chloride) led to lower selectivities for C4 sugars due to formation of hexose sugars. In the case of Sn-Beta, VGA is the main product (30 %), illustrating differences in selectivity of the Sn sites in the different frameworks. Under optimized conditions, GA can undergo further conversion, leading to yields of up to 44 % of VGA using Sn-MFI in water. The use of Sn-MFI offers multiple possibilities for valorization of biomass-derived GA in water under mild conditions selectively producing C4 molecules.
- Tolborg, S?ren,Meier, Sebastian,Saravanamurugan, Shunmugavel,Fristrup, Peter,Taarning, Esben,Sádaba, Irantzu
-
p. 3054 - 3061
(2016/11/17)
-
- Catalytic effect of aluminium chloride on the example of the conversion of sugar model compounds
-
Abstract In this work, the catalytic effect of the Bronsted acid hydrochloric acid, the Bronsted base sodium hydroxide and the Lewis acid AlCl3 on the conversion of biomass derived carbohydrates is investigated. On the example of the glycolaldehyde conversion, it is shown that the Lewis acid catalyses the ketol-endiol-tautomerism, the dehydration, the retro-aldol-reaction and the benzilic-acid-rearrangement. The main products are C4- and C6-carbohydrates as well as their secondary products 2-hydroxybut-3-enoic acid 1 and several furans. Under the same reaction conditions hydrochloric acid catalyzes mainly the dehydration and sodium hydroxide the tautomerism and subsequent aldolization.
- Schwiderski, Martin,Kruse, Andrea
-
-
- Zeolite-catalyzed isomerization of tetroses in aqueous medium
-
The isomerization of erythrose (ERO) was studied in water over commercially available large-pore zeolites, e.g. H-Y, H-USY and H-beta. Among the employed zeolites, H-USY(6) was found to efficiently isomerize the sugar, yielding 45% erythrulose (ERU), 42% ERO and 3% of the epimer threose (THO) (corresponding to the equilibrium mixture), i.e. total tetrose yield 90%, after reaction for 5-7 h at 120 °C. Changing the solvent from water to methanol decreased the yield of ERU markedly to 18% and gave only a total yield of tetroses of 27% which is significantly lower than that obtained in water. Hence, the results demonstrate that water is the preferred solvent compared to lower alcohols for zeolite-catalyzed tetrose isomerization, which is opposite to what has been found previously for analogous pentose and hexose isomerization. A reuse study revealed further that H-USY(6) could be applied for at least five reaction runs with essentially unchanged activity and without significant aluminum leaching from the catalyst. The use of benign reaction conditions and an industrially pertinent solid catalyst in combination with water establishes a new, green tetrose isomerization protocol. the Partner Organisations 2014.
- Saravanamurugan, Shunmugavel,Riisager, Anders
-
p. 3186 - 3190
(2014/08/18)
-
- ISOMERISATION OF C4-C6 ALDOSES WITH ZEOLITES
-
The present invention relates to isomerization of C4-C6 aldoses to their corresponding C4-C6 ketoses. In particular, the invention concerns isomerization of C4-C6 aldoses over solid zeolite catalysts free of any metals other than aluminum, in the presence of suitable solvent(s) at suitable elevated temperatures. C6 and C5 aldose sugars such as glucose and xylose, which are available in large amounts from biomass precursors, are isomerized to fructose and xylulose respectively, in a one or two-step process over inexpensive commercially available zeolite catalysts, containing aluminum as the only metal in the catalyst. The ketoses obtained are used as sweeteners in the food and/or brewery industry, or treated to obtain downstream platform chemicals such as lactic acid, HMF, levulinic acid, furfural, MMHB, and the like. FIG. 7
- -
-
Page/Page column 25-28
(2014/03/25)
-
- Chemoselective Pd-catalyzed oxidation of polyols: Synthetic scope and mechanistic studies
-
The regio- and chemoselective oxidation of unprotected vicinal polyols with [(neocuproine)Pd(OAc)]2(OTf)2 (1) (neocuproine = 2,9-dimethyl-1,10-phenanthroline) occurs readily under mild reaction conditions to generate α-hydroxy ketones. The oxidation of vicinal diols is both faster and more selective than the oxidation of primary and secondary alcohols; vicinal 1,2-diols are oxidized selectively to hydroxy ketones, whereas primary alcohols are oxidized in preference to secondary alcohols. Oxidative lactonization of 1,5-diols yields cyclic lactones. Catalyst loadings as low as 0.12 mol % in oxidation reactions on a 10 g scale can be used. The exquisite selectivity of this catalyst system is evident in the chemoselective and stereospecific oxidation of the polyol (S,S)-1,2,3,4-tetrahydroxybutane [(S,S)-threitol] to (S)-erythrulose. Mechanistic, kinetic, and theoretical studies revealed that the rate laws for the oxidation of primary and secondary alcohols differ from those of diols. Density functional theory calculations support the conclusion that β-hydride elimination to give hydroxy ketones is product-determining for the oxidation of vicinal diols, whereas for primary and secondary alcohols, pre-equilibria favoring primary alkoxides are product-determining. In situ desorption electrospray ionization mass spectrometry (DESI-MS) revealed several key intermediates in the proposed catalytic cycle.
- Chung, Kevin,Banik, Steven M.,De Crisci, Antonio G.,Pearson, David M.,Blake, Timothy R.,Olsson, Johan V.,Ingram, Andrew J.,Zare, Richard N.,Waymouth, Robert M.
-
supporting information
p. 7593 - 7602
(2013/07/05)
-
- Chemoselective oxidation of polyols with chiral palladium catalysts
-
Chiral palladium-based catalysts derived from pyridinyl oxazoline (pyOx) ligands catalyze the oxidation of alcohols, including 1,2-diols, triols, and tetraols, with high regio- and chemoselectivity. Screening of various chiral oxazoline-derived ligands for the oxidation of a model diol, 1,2-propanediol (1,2-PD), revealed that the nature of the ligand had a significant influence on the activity and chemoselectivity for oxidation of vicinal diols. The PyOx ligands containing an α-methyl substituent were the most active for the oxidation of 1,2-PD using benzoquinone as the terminal oxidant. Oxidation of vicinal diols and polyols occurs selectively at the secondary alcohol to afford α-hydroxy ketones in isolated yields of 62-87%. Chemoselective oxidation of meso-erythritol with the chiral [(S)-(α-Me(tert-Bu)PyOx)Pd(OAc)] 2[OTf]2 afforded (S)-erthyrulose in 62% yield and 24% ee.
- De Crisci, Antonio G.,Chung, Kevin,Oliver, Allen G.,Solis-Ibarra, Diego,Waymouth, Robert M.
-
p. 2257 - 2266
(2013/05/21)
-
- Modular microfluidic reactor and inline filtration system for the biocatalytic synthesis of chiral metabolites
-
Biocatalytic synthesis is now well established amongst catalytic methodologies as an extremely useful approach for the industrial synthesis of high-value compounds, due to its many advantages such as high reaction specificity and selectivity. However, engineering a biocatalytic process can be complex and time-consuming. This paper presents a modular microfluidic reactor and in-line filtration system for the rapid and small-scale evaluation of biocatalytic reactions. The system combines a substrate with a biocatalyst in free solution, incubates the two components until full conversion to product has been achieved, before extracting the product. The system has been applied to the transketolase-catalysed reaction of hydroxypyruvate (HPA) and glycolaldehyde (GA) to l-erythrulose, demonstrating complete conversion of substrate to product, complete retention of the enzyme and an overall yield of approximately 65%. The complete conversion of HPA and propanal to (3S)-1,3-dihydroxypentan-2- one with a mutant transketolase further demonstrated the applicability of the microfluidic system for organic synthesis.
- O'Sullivan, Brian,Al-Bahrani, Homam,Lawrence, James,Campos, Maria,Cazares, Armando,Baganz, Frank,Wohlgemuth, Roland,Hailes, Helen C.,Szita, Nicolas
-
experimental part
p. 1 - 8
(2012/06/29)
-
- Oxygen-dependent fragmentation reactions during the degradation of 1-deoxy-d-erythro-hexo-2,3-diulose
-
With this work, we report on further insights into the chemistry of 1-deoxy-d-erythro-hexo-2,3-diulose (1-deoxyglucosone, 1-DG). This α-dicarbonyl plays an important role as a highly reactive intermediate in the Maillard chemistry of hexoses. Degradation of 1-DG in the presence of the amino acid l-alanine led to the formation of several products. Lactic acid and glyceric acid were found to be major degradation products. Their formation was dependent on the presence of oxygen. Therefore, a mechanism is postulated based on oxidation leading to a tricarbonyl intermediate. Carbonyl cleavage of this structure should then give rise to carboxylic acids. This mechanism was supported by the isotope distribution observed during degradation of different 13C-labeled d-glucose isotopomers. Furthermore, we identified 3,5-dihydroxy-6-methyl-2,3-dihydro-4H-pyran-4-one (γ-pyranone) to be capable of rehydration forming 1-DG to a minor extent and therefore leading to the same degradation products. The formation of carboxylic acids from γ-pyranone was also dependent on the presence of oxygen in agreement with the postulated oxidative fragmentation. Finally, we investigated the formation of aldehydes expected as retro-aldol products formed within the degradation of 1-DG. Results seemed to rule out this reaction as an important degradation pathway under the conditions investigated herein.
- Voigt, Michael,Smuda, Mareen,Pfahler, Christoph,Glomb, Marcus A.
-
experimental part
p. 5685 - 5691
(2011/08/05)
-
- Reactivity of 1-deoxy-D-erythro-hexo-2,3-diulose; A key intermediate in the maillard chemistry of hexoses
-
Degradation of 1-deoxyhexo-2,3-diulose, a key intermediate in Maillard chemistry, in the presence of L-alanine under moderate conditions (37 and 50 °C) was investigated. Different analytical strategies were accomplished to cover the broad range of product
- Voigt, Michael,Glomb, Marcus A.
-
experimental part
p. 4765 - 4770
(2010/06/14)
-
- Synthesis with good enantiomeric excess of both enantiomers of α-ketols and acetolactates by two thiamin diphosphate-dependent decarboxylases
-
In addition to the decarboxylation of 2-oxo acids, thiamin diphosphate (ThDP)-dependent decarboxylases/dehydrogenases can also carry out so-called carboligation reactions, where the central ThDP-bound enamine intermediate reacts with electrophilic substrates. For example, the enzyme yeast pyruvate decarboxylase (YPDC, from Saccharomyces cerevisiae) or the E1 subunit of the Escherichia coli pyruvate dehydrogenase complex (PDHc-E1) can produce acetoin and acetolactate, resulting from the reaction of the central thiamin diphosphate-bound enamine with acetaldehyde and pyruvate, respectively. Earlier, we had shown that some active center variants indeed prefer such a carboligase pathway to the usual one [Sergienko, Jordan, Biochemistry 40 (2001) 7369-7381; Nemeria et al., J. Biol. Chem. 280 (2005) 21,473-21,482]. Herein is reported detailed analysis of the stereoselectivity for forming the carboligase products acetoin, acetolactate, and phenylacetylcarbinol by the E477Q and D28A YPDC, and the E636A and E636Q PDHc-E1 active-center variants. Both pyruvate and β-hydroxypyruvate were used as substrates and the enantiomeric excess was analyzed by a combination of NMR, circular dichroism and chiral-column gas chromatographic methods. Remarkably, the two enzymes produced a high enantiomeric excess of the opposite enantiomer of both acetoin-derived and acetolactate-derived products, strongly suggesting that the facial selectivity for the electrophile in the carboligation is different in the two enzymes. The different stereoselectivities exhibited by the two enzymes could be utilized in the chiral synthesis of important intermediates.
- Baykal, Ahmet,Chakraborty, Sumit,Dodoo, Afua,Jordan, Frank
-
p. 380 - 393
(2008/02/09)
-
- Methods for treating plants and enhancing plant growth using polyacylglycosides and/or polyalkylglycosides and formulations for same
-
Methods and formulations for treating plants and enhancing plant growth and for safening high concentrations of one or more phytocatalysts, wherein one or more formulations, comprising, a high concentration of one or more phytocatalysts, and an effective amount of one or more polyacylglycosides and polyalkylglycosides; and isomers, and metabolites, salts, hydrates, esters, amines, and derivatives of the polyacylglycosides and polyalkylglycosides, and combinations thereof, is applied to the plants.
- -
-
-
- Electrooxidation of mesoerythritol on platinum, modified or not by adatoms, in acid medium
-
The electrocatalytic oxidation of meso-erythritol has been studied in 0.1 M HClO4 on platinum and on adatoms modified platinum. Preliminary investigations by cyclic voltammetry showed that erythritol was not reactive on a Pt electrode. Underpotential deposition of lead or thallium adatoms at platinum allowed to increase significantly the current densities. Long-time electrolyses were carded out using a three potential plateau program with different values of the oxidation potentials. Chromatographic analyses showed that the oxidation of erythritol led mainly to erythrose, erythrulose and to erythronic acid. Otherwise, electrolysis of erythritol on a Pt-Tl modified electrode orientated selectively the distribution of the reaction products towards the formation of erythrulose.
- Cherqaoui,Chbihi,Takky,Kokoh,Leger,Lamy
-
p. 510 - 521
(2007/10/03)
-
- Glucose isomerase catalysed isomerisation reactions of (2 R,3 R)- configured aldofuranoses into the corresponding open-chain 2-ketoses
-
Immobilised glucose isomerase (EC 5.3.1.5) accepted various (2 R,3R)- configured aldofuranoses such as D-erythrose, as well as homologous C-5- modified o-ribose derivatives, as substrates. In the case of D-erythrose, quantitative conversion into D-glycero-tetrulose took place. D-Ribofuranoses were converted into the corresponding open-chain 2-ketoses in isolated yields of 65%. Surprisingly, L-erythrose also turned out to be a substrate of this enzyme.
- Ebner, Michael,Stuetz, Arnold E.
-
p. 331 - 336
(2007/10/03)
-
- 7. The chemistry of stable carbenes: Part 2 - Benzoin-type condensations of formaldehyde catalyzed by stable carbenes
-
Stable carbenes derived from thiazole, 1 H-imidazole, and 4H -1,2,4-triazole are efficient catalysts for benzoin-type condensations of formaldehyde. Catalysts derived from N-substituted thiazolium salts trimerize formaldehyde to dihydroxyacetone (II). Catalysts based on 1,4-disubstituted 4H-1,2,4-triazol-1-ium salts give glycolaldehyde (I) as the main product and no II, whereas N,N′-disubstituted 1H-imidazol-3-ium salts yield mixtures of both products. The isolation of several intermediates in the catalytic cycle provide a better insight into the reaction mechanism.
- Teles, J. Henrique,Melder, Johann-Peter,Ebel, Klaus,Schneider, Regina,Gehrer, Eugen,Harder, Wolfgang,Brode, Stefan,Enders, Dieter,Breuer, Klaus,Raabe, Gerhard
-
-
- Aldol type reaction of unprotected sugars in methanol
-
Although aldol condensation of 1,3-dihydroxyacetone with formaldehyde in methanol catalyzed by CaCl2/KOH gave glycero-tetrulose, the reaction catalyzed by Ca(OH)2 preferentially gave 1,3-dihydroxyacetone dimer. The result was explained by the formation of a chelated enolate. This sequence was successfully applied to the stereoselective synthesis of threo-3-pentulose.
- Saimoto, Hiroyuki,Yatani, Setsuo,Sashiwa, Hitoshi,Shigemasa, Yoshihiro
-
p. 937 - 938
(2007/10/02)
-
- Study of the Specificity of a Spinach Transketolase on Achiral Substrates
-
The behaviour and the specificity of a spinach transketolase towards achiral aldehydes was studied.We have shown that these aldehydes are accepted by the enzyme and yield the corresponding saccharides with good enantiomeric excess.
- Dalmas, Valerie,Demuynck, Colette
-
p. 2383 - 2388
(2007/10/02)
-
- Formose reactions, XXVIII. Selective formation of 2,4-bis(hydroxymethyl)-3-pentulose in N,N-dimethylformamide-water mixed solvent
-
Dihydroxyacetone, DL-glycero-tetrulose, and 2,4-bis(hydroxymethyl)-3-pentulose (2,4-BH-3-P) were favorably formed in a formose reaction by choosing a suitable ratio of water to N,N-dimethylformamide used as solvent or a suitable [thiamine.HCl]/[HCHO] ratio. The formose reaction was strongly affected by the concentration of formaldehyde in the water layer. Under the reaction conditions studied, thiamine decomposed rapidly. 2,4-BH-3-P was isolated from the reaction mixture and characterized by MS, IR, and NMR techniques. A pathway for the formation of 2,4-BH-3-P was also proposed.
- Shigemasa,Ueda,Saimoto
-
p. 389 - 394
(2007/10/02)
-
- ISOLATION OF AN INTERMEDIATE OF FORMOSE REACTION CATALYZED BY THIAMIN-HCl
-
2--5-(2-hydroxyethyl)-4-methylthiazole (5) was isolated in the formose reaction catalyzed by thiamin*HCl, giving an insight into the reaction mechanism of benzoin type HCHO condensation to form dihydroxyacetone.
- Saimoto, Hiroyuki,Kotani, Kazuya,Shigemasa, Yoshihiro,Suzuki, Makoto,Harada, Ken-ichi
-
p. 2553 - 2554
(2007/10/02)
-
- THE FORMOIN REACTION
-
The formoin reaction, i.e., the autocondensation of formaldehyde in an aprotic solvent catalysed by the conjugate base of a thiazolium ion, has been studied in detail.Glucose, galactose, dihyroxyacetone dimer, xylose, and arabinose have been identified as products.The influence of catalysts, temperature, basicity, and reaction time is documented.N,N-Dimethylformamide is a more convenient solvent than ether, benzene, or diglyme.Ethyldi-isopropylamine affords better yields of carbohydrate material than triethylamine.At =60 deg, aldol condensations are reduced to a minimum.After 1-2 h of reaction (depending on the conditions), the yields begin to decrease and become zero after ca. 24 h.
- Castells, Josep,Lopez-Calahorra, Francisco,Geijo, Fernando
-
p. 197 - 208
(2007/10/02)
-
- FORMATION OF 3-OCTULOSES BY A SELF-ALDOL REACTION OF D-ERYTHROSE
-
When kept at 105 deg C for 2.5 h, weakly alkaline, syrupy D-erythrose was readily converted into a mixture containing mainly D-glycero-tetrulose, the previously unknown β-D-altro-L-glycero-3-octulofuranose (2), and α-D-gluco-L-glycero-3-octulopyranose, which were isolated as the corresponding acetates.Treatment of 2 with Dowex 50 (H+) resin yielded 3,8-anhydro-β-D-altro-L-glycero-octulopyranose, identified as its acetate.Previous discrepancies in the D values for D-erythrose appear partly to originate in the self-aldol reaction.The dimerisation of D-erythrose 4-phosphate is also described.
- Westerlund, Eric
-
-
- Radical-Induced Dephosphorylation of Fructose Phosphates in Aqueous Solution
-
Oxygen free N2O-saturated aqueous solutions of D-fructose-1-phosphate and D-fructose-6-phosphate were γ-irradiated.Inorganic phosphate and phosphate free sugars (containing four to six carbon atoms) were identified and their G-values measured.D-Fructose-1-phosphate yields (G-values in parentheses) inorganic phosphate (1.6), hexos-2-ulose (0.12), 6-deoxy-2,5-hexodiulose (0.16), tetrulose (0.05) and 3-deoxytetrulose (0.15).D-Fructose-6-phosphate yields inorganic phosphate (1.7), hexos-5-ulose (0.1), 6-deoxy-2,5-hexodiulose (0.36), 3-deoxy-2,5-hexodiulose and 2-deoxyhexos-5-ulose (together 0.18).On treatment with alkaline phosphate further deoxy sugars were recognized and in fructose-1-phosphate G(6-deoxy-2,5-hexodiulose) was increased to a G-value of 0.4.Dephosphorylation is considered to occur mainly after OH attack at C-5 and C-1 in fructose-1-phosphate and at C-5 and C-6 in fructose-6-phosphate.Reaction mechanisms are discussed. - Keywords: D-Fructose-1-phosphate, D-Fructose-6-phosphate, γ-Irradiation; Radical Reactions, Mass Spectrometry
- Zegota, Henryk,Sonntag, Clemens von
-
p. 1331 - 1337
(2007/10/02)
-