Degradation, of glutathione

Figure 12. Degradation of glutathione conjugates of 2,2, 5,5 -tetrachloroblphenyl In water and methanol as suggested by Preston et al. (180).

The degradation of glutathione in animals and microorganisms probably takes place mainly by transpeptidation ... 

Cysteine [52-90 ] is a thiol-bearing amino acid which is readily isolated from the hydrolysis of protein. There ate only small amounts of cysteine and its disulfide, cystine, in living tissue (7). Glutathione [70-18-8] contains a mercaptomethyl group, HSCH2, and is a commonly found tripeptide in plants and animals. Coenzyme A [85-61-0] is another naturally occurring thiol that plays a central role in the synthesis and degradation of fatty acids. 

An exopeptidase that can only degrade a dipeptide. Examples are carnosine dipeptidase I (MEROPS M20.006), which degrades carnosine (beta-Ala-His), and membrane dipeptidase (MEROPS Ml9.001), which is important in the catabolism of glutathione, degrading the dipeptides Cys-Gly. Dipeptidases are included in Enzyme Nomenclature sub-subclass 3.4.13. 

The degradation of isoprene by Rhodococcus sp. strain AD45 involves a glutathione-mediated reaction (van Hylckama Vlieg et al. 2000) and is noted again in Chapter 7, Part 1. 

The degradation of vinyl chloride and ethene has been examined in Mycobacterium sp. strain JS 60 (Coleman and Spain 2003) and in Nocardioides sp. strain JS614 (Mattes et al. 2005). For both substrates, the initially formed epoxides underwent reaction with reduced coenzyme M and, after dehydrogenation and formation of the coenzyme A esters, reductive loss of coenzyme M acetate resulted in the production of 5-acetyl-coenzyme A. The reductive fission is formally analogous to that in the glutathione-mediated reaction. 

D-Arginine and D-ornithine metabolism D-Alanine metabolism Glutathione metabolism Alkaloid biosynthesis I Alkaloid biosynthesis II Metabolism of Complex Carbohydrates Starch and sucrose metabolism Biosynthesis and degradation of glycoprotein... 

It was recently discovered that 5. cerevisiae Ubrlp and Ufd4p, the E3 components of two distinct Ub-dependent proteolytic pathways, directly interact with specific proteins of the 26S proteasome (1). These results stemmed from the initial finding that overexpression of some subunits of the 19S particle inhibited ubiquitin-dependent degradation of engineered N-end rule substrates. To determine whether this effect could be caused by interaction of these subunits with a component(s) of the N-end rule pathway, glutathione transferase (GST)-pulldown assays with Ubrlp (also called... 

Insulin is removed from the circulation by the liver and the kidney. The disulfide connections between the A and B chains are hydrolyzed through the action of glutathione insulin trans-hydrogenase. After this cleavage further degradation occurs by proteolysis. In patients treated with subcutaneous insulin injections the clearance by the liver is 40% and by the kidney 60%. The half-life of circulating insulin is 3-5 min. 

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