Deamination glucosamines

Deamination, glucosamines, 16 Dehydro names, aldoketoses, 80 Deoxyalditols, 83... 

Amino-sugars and Related Compounds. Part I. The Deamination of D-Glucosamine Hydrochloride, B. C. Bera, A. B. Foster, andM. Stacey,/. Chem. Soc., (1956) 4531-4535. 

Let us now return to the pioneering work of Fischer and Tiemann.4 Chitonic acid is produced from D-glucosamine by deamination and oxidation, in that order. If the order is reversed, however, i. e., if D-glucos-amine is first oxidized to D-glucosaminic acid (2-amino-D-gIuconic acid) and the latter substance subsequently deaminated, chitonic acid is not the product. Instead an isomeric 2,5-anhydro hexonic acid (chitaric acid) is obtained. These facts may be summarized thus ... 

Further consideration needs to be given to the interesting fact that although D-glucosaminic acid (2-amino-D-gluconic acid) undergoes de-amination. with the establishment of a 2,5-anhydro ring, the deamination... 

In May, 1944, Onodera was promoted to Associate Professor. After 1950, the condition of scientific research in Japan gradually improved, and Onodera and his associates succeeded in publishing the following results deamination of D-glucosamine by barium hypobromite (1952) transgly-... 

This enzyme [EC 5.3.1.10] catalyzes the following isomerization and deamination reaction o-glucosamine 6-phosphate + H2O o-fructose 6-phosphate + NH3. 

Deamination of N-deacetylated glycosamino-glycans followed by sodium borodeuteride reduction led to pseudo-disaccharides of 2,5-anhydro-D-mannitol or -D-talitol (from D-glucosamine and D-galact-osamine residues respectively) with attached glucuronic acid,... 

Take five 15-ml centrifuge tubes. To two add 2 ml of 6n hydrochloric acid to act as blanks and to three others add 2.00 ml of dilute standard from a pipette. Continue the method exactly as described in Section E from paragraph 2 on, heating for the same period of time (between 4 and 8 hr) as used with samples. (Glucosamine is slowly deaminated in acid and the extent depends upon the time of heating.)... 

Leloir and Cardini (1956) first found an enzyme in pig kidney cortex which catalyzed the synthesis of glucosamine-6-phosphate. The equilibrium of the enzyme reaction is strongly in favor of deamination. However, Comb and Roseman (1958a) showed that by coupling to a second enzyme (acetylase) the reaction can be pulled in the direction of synthesis. This enzyme (deaminase) apparently is ubiquitous and is stimulated by the presence of A -acetylglucosamine-6-phosphate. 

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