Glucose enzymatic transformation

L2. Leloir, L. F., The enzymatic transformation of uridine diphosphate glucose into a galactose derivative. Arch. Biochem. Biophys. 33, 186-190 (1951). 

In fluorine-18 chemistry some enzymatic transformations of compounds already labelled with fluorine-18 have been reported the synthesis of 6-[ F] fluoro-L-DOPA from 4-[ F]catechol by jS-tyrosinase [241], the separation of racemic mixtures of p F]fluoroaromatic amino acids by L-amino acylase [242] and the preparation of the coenzyme uridine diphospho-2-deoxy-2-p F]fluoro-a-o-glucose from [ F]FDG-1-phosphate by UDP-glucose pyrophosphorylase [243]. In living nature compounds exhibiting a carbon-fluorine bond are very rare. 

A chemoenzymatic synthesis of di-, tetra-, and octavalent sialyl Lewis X ligands scaffolded on dendrimers has been reported (Scheme 67). 508 Hypervalent L-lysine cores with covalently attached 2-acetamido-2-deoxy-D-glucose residues were chemically prepared and enzymatically transformed into sialyl Lewis X-containing dendrimers using (3-(l— 4) ga-... 

The leaves of Rubus smvissimus S. Lee (Rosaceae), which is found wild in Guang Xi province in China, show potent sweetness and are used as a drink (sweet tea tian-cha). Rubusoside has been isolated as a major sweet component from the leaves.28 This compound has the same aglycon structure as stevioside but with one glucose less and can be obtained from stevioside by enzymatic transformation. Rubusoside is 130 times sweeter than sucrose. A comprehensive review of stevioside has been published.29... 

Scheme 7.16 Enzymatic transformation of D-glucose to c/s,c s-muconic acid and subsequent hydrogenation to AA. Source elaborated from [42c].

K14. Kopwillem, A., Analytical isotachophoresis I. Separation of ions involved in the enzymatic transformation of glucose to 6-phospho-gluconate. LKB Appl. Note No. 59 (1973). 

The pathways (a), (c) and (d) are also operative in the methionine/D-glucose Maillard systems. The degradation pathways indicate analogy to the enzymatic transformations and are reported for the first time. 

Increasingly, biochemical transformations are used to modify renewable resources into useful materials (see Microbial transformations). Fermentation (qv) to ethanol is the oldest of such conversions. Another example is the ceU-free enzyme catalyzed isomerization of glucose to fmctose for use as sweeteners (qv). The enzymatic hydrolysis of cellulose is a biochemical competitor for the acid catalyzed reaction. 

Fructose has a much sweeter taste than glucose, hence the transformation of glucose derived from enzymatic hydrolysis of starch from com, provides an alternative sweetener to sucrose (a disaccharide of glucose and fructose). This replaced the use of sugar cane by the US soft drinks and candy industry (and effectively destroyed the economy of Cuba in the process). 

Glucose reacts non-enzymatically with amino acids and proteins, including hemoglobin, egg-white proteins and serum albumin. For example, if glucose is not removed prior to drying, dried egg whites slowly turn brown and develop off-flavors and odors. What do you propose as the most likely first step in the non-enzymatic glucose-protein chemical reaction How can the first product transform spontaneously into a ketose derivative ... 

Since the invertase enzyme was purchased 2 years ago from the time this experiment is performed, it was necessary to determine its activity. Knowing that an enzymatic unit corresponds to the amount of enzyme causing the transformation of 1.0 pM of substrate per minute. The equivalent of the response of the enzyme has been given in concentration of the substrate from the linear regression equation of the glucose response. For both sucrose and glucose the experiments have been done in the same conditions of pH value and applied potential. After extrapolation of the invertase response we have found that the activity of invertase is equal to 140 U/mg. 

Process (e.g., enzymatic breakdown) whereby an organic compound is transformed to a simpler carbon entity (e.g., glucose to carbon dioxide). Volume 2(1,7). 

Glycation reactions. Glucose or other sugars may react non-enzymatically with proteins to form glycation products. Early glycation products such as fructosamine-protein adducts may later be transformed to the more complex advanced glycation end products (AGE products). 

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