533-50-6Relevant articles and documents
Microfluidic multi-input reactor for biocatalytic synthesis using transketolase
Lawrence, James,O'Sullivan, Brian,Lye, Gary J.,Wohlgemuth, Roland,Szita, Nicolas
, p. 111 - 117 (2013)
Biocatalytic synthesis in continuous-flow microreactors is of increasing interest for the production of specialty chemicals. However, the yield of production achievable in these reactors can be limited by the adverse effects of high substrate concentration on the biocatalyst, including inhibition and denaturation. Fed-batch reactors have been developed in order to overcome this problem, but no continuous-flow solution exists. We present the design of a novel multi-input microfluidic reactor, capable of substrate feeding at multiple points, as a first step towards overcoming these problems in a continuous-flow setting. Using the transketolase-(TK) catalysed reaction of lithium hydroxypyruvate (HPA) and glycolaldehyde (GA) to l-erythrulose (ERY), we demonstrate the transposition of a fed-batch substrate feeding strategy to our microfluidic reactor. We obtained a 4.5-fold increase in output concentration and a 5-fold increase in throughput compared with a single input reactor.
L-erythrulose production by oxidative fermentation is catalyzed by PQQ-containing membrane-bound dehydrogenase.
Moonmangmee, Duangtip,Adachi, Osao,Shinagawa, Emiko,Toyama, Hirohide,Theeragool, Gunjana,Lotong, Napha,Matsushita, Kazunobu
, p. 307 - 318 (2002)
Thermotolerant Gluconobacter frateurii CHM 43 was selected for L-erythrulose production from mesoerythritol at higher temperatures. Growing cells and the membrane fraction of the strain rapidly oxidized mesoerythritol to L-erythrulose irreversibly with almost 100% of recovery at 37 degrees C. L-Erythrulose was also produced efficiently by the resting cells at 37 degrees C with 85% recovery. The enzyme responsible for mesoerythritol oxidation was found to be located in the cytoplasmic membrane of the organism. The EDTA-resolved enzyme required PQQ and Ca2+ for L-erythrulose formation, suggesting that the enzyme catalyzing meso-erythritol oxidation was a quinoprotein. Quinoprotein membrane-bound mesoerythritol dehydrogenase (QMEDH) was solubilized and purified to homogeneity. The purified enzyme showed a single band in SDS-PAGE of which the molecular mass corresponded to 80 kDa. The optimum pH of QMEDH was found at pH 5.0. The Michaelis constant of the enzyme was found to be 25 mM for meso-erythritol as the substrate. QMEDH showed a broad substrate specificity toward C3-C6 sugar alcohols in which the erythro form of two hydroxy groups existed adjacent to a primary alcohol group. On the other hand, the cytosolic NAD-denpendent meso-erythritol dehydrogenase (CMEDH) of the same organism was purified to a crystalline state. CMEDH showed a molecular mass of 60 kDa composed of two identical subunits, and an apparent sedimentation constant was 3.6 s. CMEDH catalyzed oxidoreduction between mesoerythritol and L-erythrulose. The oxidation reaction was observed to be reversible in the presence of NAD at alkaline pHs such as 9.0-10.5. L-Erythrulose reduction was found at pH 6.0 with NADH as coenzyme. Judging from the catalytic properties, the NAD-dependent enzyme in the cytosolic fraction was regarded as a typical pentitol dehydrogenase of NAD-dependent and the enzyme was independent of the oxidative fermentation of L-erythrulose production.
Enantioselective Reductive Oligomerization of Carbon Dioxide into l-Erythrulose via a Chemoenzymatic Catalysis
Bontemps, Sébastien,Clapés, Pere,Desmons, Sarah,Dumon, Claire,Fauré, Régis,Grayson-Steel, Katie,Hurtado, John,Nu?ez-Dallos, Nelson,Vendier, Laure
supporting information, p. 16274 - 16283 (2021/10/12)
A cell-free enantioselective transformation of the carbon atom of CO2has never been reported. In the urgent context of transforming CO2into products of high value, the enantiocontrolled synthesis of chiral compounds from CO2would be highly desirable. Using an original hybrid chemoenzymatic catalytic process, we report herein the reductive oligomerization of CO2into C3(dihydroxyacetone, DHA) and C4(l-erythrulose) carbohydrates, with perfect enantioselectivity of the latter chiral product. This was achieved with the key intermediacy of formaldehyde. CO2is first reduced selectively by 4e-by an iron-catalyzed hydroboration reaction, leading to the isolation and complete characterization of a new bis(boryl)acetal compound derived from dimesitylborane. In an aqueous buffer solution at 30 °C, this compound readily releases formaldehyde, which is then involved in selective enzymatic transformations, giving rise either (i) to DHA using a formolase (FLS) catalysis or (ii) to l-erythrulose with a cascade reaction combining FLS and d-fructose-6-phosphate aldolase (FSA) A129S variant. Finally, the nature of the synthesized products is noteworthy, since carbohydrates are of high interest for the chemical and pharmaceutical industries. The present results prove that the cell-freede novosynthesis of carbohydrates from CO2as a sustainable carbon source is a possible alternative pathway in addition to the intensely studied biomass extraction andde novosyntheses from fossil resources.
PROCESSES FOR PREPARING C-4 SUGARS AND KETOSE SUGARS
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Page/Page column 37-39, (2021/11/20)
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.
D -Serine as a Key Building Block: Enzymatic Process Development and Smart Applications within the Cascade Enzymatic Concept
Auffray, Pascal,Charmantray, Franck,Collin, Jér?me,Hecquet, Laurence,L'Enfant, Mélanie,Martin, Juliette,Ocal, Nazim,Pollegioni, Loredano
, p. 769 - 775 (2020/07/14)
An efficient enzymatic method catalyzed by an enzyme from the d-threonine aldolase (DTA) family was developed for d-serine production at industrial scale. This process was used for the synthesis of two valuable ketoses, l-erythrulose and d-fructose, within the cascade enzymatic concept involving two other enzymes. Indeed, d-serine was used as a substrate of d-amino acid oxidase (DAAO) for the in situ generation of the corresponding α-keto acid, hydroxypyruvic acid (HPA), a key donor substrate of transketolase (TK). This enzyme catalyzed the irreversible transfer of the ketol group from HPA to an aldehyde acceptor to form a (3S)-ketose by stereoselective carbon-carbon bond formation. The compatibility of all enzymes and substrates allowed a sequential three-step enzymatic process to be performed without purification of the intermediates. This strategy was validated with two TK aldehyde substrates to finally obtain the corresponding (3S)-ketoses with high control of the stereoselectivity and excellent aldehyde conversion rates.
One-Pot Cascade Synthesis of (3S)-Hydroxyketones Catalyzed by Transketolase via Hydroxypyruvate Generated in Situ from d-Serine by d-Amino Acid Oxidase
L'enfant, Mélanie,Bruna, Felipe,Lorillière, Marion,Ocal, Nazim,Fessner, Wolf-Dieter,Pollegioni, Loredano,Charmantray, Franck,Hecquet, Laurence
, p. 2550 - 2558 (2019/04/17)
We described an efficient in situ generation of hydroxypyruvate from d-serine catalyzed by a d-amino acid oxidase from Rhodotorula gracilis. This strategy revealed an interesting alternative to the conventional chemical synthesis of hydroxypyruvate starting from toxic bromopyruvate or to the enzymatic transamination from l-serine requiring an additional substrate as amino acceptor. Hydroxypyruvate thus produced was used as donor substrate of transketolases from Escherichia coli or from Geobacillus stearothermophilus catalyzing the stereoselective formation of a carbon?carbon bond. The enzymatic cascade reaction was performed in one-pot in the presence of d-serine and appropriate aldehydes for the synthesis of valuable (3S)-hydroxyketones, which were obtained with high enantio- and diastereoselectivity and in good yield. The efficiency of the process was based on the irreversibility of both reactions allowing complete conversion of d-serine and aldehydes. (Figure presented.).
Separating Thermodynamics from Kinetics—A New Understanding of the Transketolase Reaction
Marsden, Stefan R.,Gjonaj, Lorina,Eustace, Stephen J.,Hanefeld, Ulf
, p. 1808 - 1814 (2017/05/26)
Transketolase catalyzes asymmetric C?C bond formation of two highly polar compounds. Over the last 30 years, the reaction has unanimously been described in literature as irreversible because of the concomitant release of CO2 if using lithium hydroxypyruvate (LiHPA) as a substrate. Following the reaction over a longer period of time however, we have now found it to be initially kinetically controlled. Contrary to previous suggestions, for the non-natural conversion of synthetically more interesting apolar substrates, the complete change of active-site polarity is therefore not necessary. From docking studies it was revealed that water and hydrogen-bond networks are essential for substrate binding, thus allowing aliphatic aldehydes to be converted in the charged active site of transketolase.
Efficient Production of Biomass-Derived C4 Chiral Synthons in Aqueous Solution
Lin, Shaoying,Guo, Xiao,Qin, Kai,Feng, Lei,Zhang, Yahong,Tang, Yi
, p. 4179 - 4184 (2017/12/02)
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.
ISOMERISATION OF C4-C6 ALDOSES WITH ZEOLITES
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Page/Page column 25-28, (2014/03/25)
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
Zeolite-catalyzed isomerization of tetroses in aqueous medium
Saravanamurugan, Shunmugavel,Riisager, Anders
, p. 3186 - 3190 (2014/08/18)
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.
