3616-21-5

Upstream product

• 110-86-1 pyridine 
• 2438-80-4 L-Fucose 
• 92418-41-2 L-Fuculose-1-phosphate 
• 73804-38-3 1-deoxy-L-altritol 
• 3615-41-6 L-Rhamnose 
• 38088-18-5 1-deoxy-L-psicose 

Downstream Products

• 7658-10-8 6-Deoxy-L-talose 
• 32738-74-2 6-deoxy-L-galactose 
• 1026722-79-1 6-deoxy-L-ribo-hexulose 
• 14807-05-7 6-deoxy-L-arabino-2-hexulose 

Relevant academic research and scientific papers

Aldose-ketose interconversion in pyridine in the presence of aluminium oxide

The reaction rate of the Lobry de Bruyn-Alberda van Ekenstein transformation of aldoses to ketoses in boiling pyridine was strongly increased by the addition of aluminium oxide. In addition to aldose-ketose transformation, 2-epimers of the starting aldoses and 3-epimers of the primarily produced ketoses were formed to some extent, as reported also when these reactions are carried out without aluminium oxide. The relative amounts of the primary ketose and the starting aldose in the reaction mixtures may be explained on the basis of their stability, predicted from reported free energy calculations. Isomerisation of ketoses to aldoses was much slower than the reverse reaction. The relative free energies are also in these cases important, the very stable xylo-2-hexulose gave only 7% and 6% of the aldoses gulose and idose, respectively, after boiling for 7 h in pyridine in the presence of aluminium oxide.

Characterization of a novel D-arabinose isomerase from Thermanaeromonas toyohensis and its application for the production of D-ribulose and L-fuculose

D-Ribulose and L-fuculose are potentially valuable rare sugars useful for anticancer and antiviral drugs in the agriculture and medicine industries. These rare sugars are usually produced by chemical methods, which are generally expensive, complicated and do not meet the increasing demands. Furthermore, the isomerization of D-arabinose and L-fucose byDD-arabinose and L-fucose by D-arabinose isomerase from bacterial sources for the production of D-ribulose and L-fuculose have not yet become industrial due to the shortage of biocatalysts, resulting in poor yield and high cost of production. In this study, a thermostable D-ribulose- and L-fuculose producing D-arabinose isomerase from the bacterium Thermanaeromonas toyohensis was characterized. The recombinant D-arabinose isomerase from T. toyohensis (Thto-DaIase) was purified with a single band at 66 kDa using His-trap affinity chromatography. The native enzyme existed as a homotetramer with a molecular weight of 310 kDa, and the specific activities for both D-arabinose and L-fucose were observed to be 98.08 and 85.52 U mg?1, respectively. The thermostable recombinant Thto-DaIase was activated when 1 mM Mn2+ was added to the reactions at an optimum pH of 9.0 at 75 °C and showed approximately 50% activity for both D-arabinose and L-fucose at 75 °C after 10 h. The Michaelis-Menten constant (Km), the turnover number (kcat) and catalytic efficiency (kcat/Km) for D-arabinose/L-fucose were 111/81.24 mM, 18,466/10,688 min?1, and 166/132 mM?1 min?1, respectively. When the reaction reached to equilibrium, the conversion rates of D-ribulose from D-arabinose and L-fuculose from L-fucose were almost 27% (21 g L?1) and 24.88% (19.92 g L?1) from 80 g L?1 of D-arabinose and L-fucose, respectively.

Efficient enzymatic synthesis of l-rhamnulose and l-fuculose

l-Rhamnulose (6-deoxy-l-arabino-2-hexulose) and l-fuculose (6-deoxy-l-lyxo-2-hexulose) were prepared from l-rhamnose and l-fucose by a two-step strategy. In the first reaction step, isomerization of l-rhamnose to l-rhamnulose, or l-fucose to l-fuculose was combined with a targeted phosphorylation reaction catalyzed by l-rhamnulose kinase (RhaB). The by-products (ATP and ADP) were selectively removed by silver nitrate precipitation method. In the second step, the phosphate group was hydrolyzed to produce l-rhamnulose or l-fuculose with purity exceeding 99% in more than 80% yield (gram scale).

Molecular characterization of a thermostable l-fucose isomerase from Dictyoglomus turgidum that isomerizes l-fucose and d-arabinose

A recombinant thermostable l-fucose isomerase from Dictyoglomus turgidum was purified with a specific activity of 93 U/mg by heat treatment and His-trap affinity chromatography. The native enzyme existed as a 410 kDa hexamer. The maximum activity for l-fucose isomerization was observed at pH 7.0 and 80 °C with a half-life of 5 h in the presence of 1 mM Mn2+ that was present one molecular per monomer. The isomerization activity of the enzyme with aldose substrates was highest for l-fucose (with a kcat of 15,500 min-1 and a Km of 72 mM), followed by d-arabinose, d-altrose, and l-galactose. The 15 putative active-site residues within 5 A of the substrate l-fucose in the homology model were individually replaced with other amino acids. The analysis of metal-binding capacities of these alanine-substituted variants revealed that Glu349, Asp373, and His539 were metal-binding residues, and His539 was the most influential residue for metal binding. The activities of all variants at 349 and 373 positions except for a dramatically decreased kcat of D373A were completely abolished, suggesting that Glu349 and Asp373 were catalytic residues. Alanine substitutions at Val131, Met197, Ile199, Gln314, Ser405, Tyr451, and Asn538 resulted in substantial increases in Km, suggesting that these amino acids are substrate-binding residues. Alanine substitutions at Arg30, Trp102, Asn404, Phe452, and Trp510 resulted in decreases in kcat, but had little effect on Km.

DEOXYKETOHEXOSE ISOMERASE AND METHOD FOR PRODUCING DEOXYHEXOSE AND DERIVATIVE THEREOF USING SAME

Providing 1- or 6-deoxy products corresponding to all of aldohexoses, ketohexoses and sugar alcohols, as based on Deoxy-Izumoring, as well as a method for systematically producing those products. A method for producing deoxyketohexose and a derivative thereof using a deoxyketohexose isomerase derived from Pseudomonas cichorii ST-24 (FERM BP-2736), comprising epimerizing 1-deoxy D-ketohexose or 6-deoxy D-ketohexose or 1-deoxy L-ketohexose or 6-deoxy L-ketohexose at position 3 to produce the individually corresponding 1-deoxy D-ketohexose or 6-deoxy D-ketohexose or 1-deoxy L-ketohexose or 6-deoxy L-ketohexose as an intended product.

Conversion of l-rhamnose into ten of the sixteen 1- and 6-deoxyketohexoses in water with three reagents: d-tagatose-3-epimerase equilibrates C3 epimers of deoxyketoses

The efficient isomerization of l-rhamnose [the only cheaply available deoxy hexose] to 1-deoxy-l-psicose, 1-deoxy-d-psicose, 1-deoxy-l-fructose, 1-deoxy-d-fructose, 1-deoxy-l-tagatose, 6-deoxy-l-psicose, 6-deoxy-d-psicose, 6-deoxy-l-fructose, 6-deoxy-d-fructose, and 6-deoxy-l-tagatose is described. The conversion of rhamnose to ten of the sixteen 1- and 6-deoxyketohexoses is accomplished in water in three steps. The range of substrates for d-tagatose-3-epimerase (DTE) is extended to 1- and 6-deoxyketoses. An authentic sample of 6-deoxy-d-psicose is prepared from d-psicose.

Base catalysed isomerisation of aldoses of the arabino and lyxo series in the presence of aluminate

Base-catalysed isomerisation of aldoses of the arabino and lyxo series in aluminate solution has been investigated. L-Arabinose and D-galactose give L-erythro-2-pentulose (L-ribulose) and D-lyxo-2-hexulose (D-tagatose), respectively, in good yields, whereas lower reactivity is observed for 6-deoxy-D-galactose (D-fucose). From D-lyxose, D-mannose and 6-deoxy-L-mannose (L-rhamnose) are obtained mixtures of ketoses and C-2 epimeric aldoses. Small amounts of the 3-epimers of the ketoses were also formed. 6-Deoxy-L-arabino-2-hexulose (6-deoxy-L-fructose) and 6-deoxy-L-glucose (L-quinovose) were formed in low yields from 6-deoxy-L-mannose and isolated as their O-isopropylidene derivatives. Explanations of the differences in reactivity and course of the reaction have been suggested on the basis of steric effects.