Glycine degradation

In the third and final pathway of glycine degradation, the achiral glycine molecule is a substrate for the enzyme D-amino acid oxidase. The glycine is converted to glyoxylate, an alternative substrate for hepatic lactate... 

According to Kato et al.,329 nondialysable melanoidins from glucose-glycine degrade nitrite and prevent nitrosamine formation, both maximally at pH 1.2. Treatment with nitrite greatly enhances the antimutagenicity of the melanoidins. 

Glycine degradation by bovine spermatozoa is thought to go through glyoxylate, formate, and CO2 (Flipse and Benson, 1957). A folic coenzyme, if required here, should be extraordinarily interesting Does the spermatozoon retain the folic coenzyme used in the synthesis of its DNA ... 

Most pteridines are degraded to pyrazines and when they do yield pyrimidines, these may well be the ones from which they were made. However, some useful preparations of pyrimidines from pteridines are known. Thus, reduction of pteridin-7(8//)-one (732) and subsequent hydrolysis yields N-(4-aminopyrimidin-5-yl)glycine (733) (52JCS1620) and hydrolysis of 5,8-dimethylpteridine-6,7(5Ff,8Ff)-dione (734) gives dimethyl-... 

The substance represented by formula (IV), viz., 4-hydroxy-3-allyl-3 4-dihydroqviinazoline, m.p. 130°, was synthesised by Reynolds and Robinson, and proved to be different from vasicine. Spath and Kuffner established the identity of the degradation product (V), upon which formula (IV) for vasicine was chiefly based by synthesis from isatoic anhydride, which, on treatment with glycine ester hydrochloride and sodium meth-oxide, gave the substituted Wppuric acid (VI), and this, on heating with... 

Tetanus is a disease caused by the release of neurotoxins from the anaerobic, spore-forming rod Clostridium tetani. The clostridial protein, tetanus toxin, possesses a protease activity which selectively degrades the pre-synaptic vesicle protein synaptobrevin, resulting in a block of glycine and y-aminobutyric acid (GABA) release from presynaptic terminals. Consistent with the loss of neurogenic motor inhibition, symptoms of tetanus include muscular rigidity and hyperreflexia. The clinical course is characterized by increased muscle tone and spasms, which first affect the masseter muscle and the muscles of the throat, neck and shoulders. Death occurs by respiratory failure or heart failure. 

Since biosynthesis of IMP consumes glycine, glutamine, tetrahydrofolate derivatives, aspartate, and ATP, it is advantageous to regulate purine biosynthesis. The major determinant of the rate of de novo purine nucleotide biosynthesis is the concentration of PRPP, whose pool size depends on its rates of synthesis, utilization, and degradation. The rate of PRPP synthesis depends on the availabihty of ribose 5-phosphate and on the activity of PRPP synthase, an enzyme sensitive to feedback inhibition by AMP, ADP, GMP, and GDP. 

Verleysdonk, S, Martin, H, Willker, W, Leibfritz, D and Hamprecht, B (1999) Rapid uptake and degradation of glycine by astroglial cells in culture synthesis and release of serine and lactate. Glia 27 239-248. 

This enzyme catalyzes the conversion of pyruvate to formate and acetyl CoA and is a key enzyme in the anaerobic degradation of carbohydrates in some Enterobacteriaceae. Using an enzyme selectively C-labeled with glycine, it was shown by EPR that the reaction involves production of a free radical at C-2 of glycine (Wagner et al. 1992). This was confirmed by destruction of the radical with O2, and determination of part of the structure of the small protein that contained an oxalyl residue originating from gly-734. 

GLYCINE AS A CENTRAL NEUROTRANSMITTER GLYCINE SYNTHESIS, UPTAKE AND DEGRADATION 298... 

There are also several reports of Li+-induced effects upon the endorphins (see ref. 162). More recently it has been shown that Li+ also enhances the activity of tyrosine aminopeptidase in rat pituitary gland [167]. This could result in changes in the levels of the enkephalins which are primarily degraded by aminopeptidases via cleavage of the tyrosine-glycine amide bond [168]. 

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