Animals amino acid conjugates

In the past decade, several aspects of xenobiotic conjugation have been studied In aquatic animals. This paper will summarize and review recent findings, with particular emphasis on glycosylation, glutathione conjugation and mercapturlc acid biosynthesis, and amino acid conjugation. 

Xenobiotics that contain a free or potential carboxyl group can be metabolized by amino acid conjugation in both plants and animals. This reaction is illustrated by the conjugation of 2,4-D with aspartic acid (Equation 31). In higher plants, amino acid conjugation is... 

Clearly, more studies are required In this area before one can usefully generalise, although It does appear from the limited data available that amino acid conjugates of small polar molecules may not necessarily be terminal metabolites In animals they may be hydrolyzed, and the exocon excreted without further conjugation. 

The S. A-E are components of the dried, Chinese Saussurea root (Saussurea costus, syn. 5. lappa) which is used in Chinese and Japanese traditional medicine for stomach complaints. S. A, C20H29NO4, Mr 347.45, mp, 115-117°C, [a]i3 +36.7° (CH3OH), corresponds to the Michael adduct from costunolide and proline S. B and C represent the amino acid conjugates of proline and asparagine, respectively, with the corresponding a, 8-unsaturated dehydrocostus lactone. In animal experiments, S. A exhibits a pronounced protective effect against stress-induced stomach ulcers. 

A number of amino acids can be used for conjugation of aromatic acids but the most common is glycine. Others utilized are taurine, glutamine, ornithine, for example. However, the one used may depend on the species of animal. 

Amino acid analysis is widely applied in research, clinical facilities, and industry. It is a fundamental technique in biotechnology, used to determine the concentration of peptide solutions, to confirm protein binding in antibody conjugates, and for end-terminal analysis following enzymatic digestion. Clinical applications include diagnosing metabolic disorders in newborns. In industry, it is used for quality control of products ranging from animal feed to infant formula. 

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