Gelatin decomposition products

Collagens are quantitatively the most abundant of animal proteins, representing 25% of the total. They form insoluble tensile fibers that occur as structural elements of the extracellular matrix and connective tissue throughout the body. Their name (which literally means glue-producers ) is derived from the gelatins that appear as a decomposition product when collagen is boiled. 

Serine is, as yet, the only member of the oxyaraino acids of the aliphatic series which has been isolated with certainty from the mixture of decomposition products of the proteins. It was first obtained in 1865 by Cramer from silk-gelatin, and was not again obtained until E. Fischer isolated it from the various proteins which he emd his pupils have examined. 

In a rare autosomal recessive condition (discovered in 1954) the urine and perspiration has a maple syrup odor/ High concentrations of the branched-chain 2-oxoacids formed by transamination of valine, leucine, and isoleucine are present, and the odor arises from decomposition products of these acids. The branched-chain amino acids as well as the related alcohols also accumulate in the blood and are found in the urine. The biochemical defect lies in the enzyme catalyzing oxidative decarboxylation of the oxoacids, as is indicated in Fig. 24-18. Insertions, deletions, and substitutions may be present in any of the subunits (Figs. 15-14,15-15). The disease which may affect one person in 200,000, is usually fatal in early childhood if untreated. Children suffer seizures, mental retardation, and coma. They may survive on a low-protein (gelatin) diet supplemented with essential amino acids, but treatment is difficult and a sudden relapse is apt to prove fatal. Some patients respond to administration of thiamin at 20 times the normal daily requirement. The branched-chain oxoacid dehydrogenase from some of these children shows a reduced affinity for the essential coenzyme thiamin diphosphate.d... 

The soluble uranium species produced was stable at 200°C for at least three hours, at which time the temperature was gradually increased from 200°C to 300°C over a period of one hour. Suspended solids were first noted at 300°C. The temperature was increased to 350°C for one hour, then to 400°C for 0.5 hour. The solids produced through the thermal decomposition of the soluble uranium species were accompanied by gas evolution. We did not determine if this gas evolution was simply removal of excess nitric acid from the melt or a decomposition product. The solids were formed uniformly throughout the melt and had a gelatinous appearance. These solids settled very slowly to the bottom of the reaction tube. The final product of this second test was also recovered by aqueous dissolution of... 

Hydrolysis of phosphites can be discussed from several points of view. Thus, besides their applications as flame retardants and stabilizers for polymers discussed earlier, [130] related phosphoric acid esters are constituents of important biomolecules (nucleotides). The reaction of the latter with water is a central aspect of their transformation, for example, activation and generation of energy. In hydroformylation, knowledge about the pathways and the nature of decomposition products is necessary to maintain a stable catalytic regime. Moreover, the formation of such acidic compounds over time can lead to the precipitation of insoluble gelatinous byproducts, which may block the recycle lines of a continuous technical reactor. 

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