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.
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.
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.