Polyamines degradation

YodaH,YamaguchiY, SanoH (2003) Induction of hypersensitive ceU death by hydrogen peroxide produced through polyamine degradation in tobacco plants. Plant Physiol 132 1973-1981... 

Werner C et ai, Degradation of the polyamine alkaloid aphelandrine by endophytic fungi isolated irom Aphelandra tetragona, FEMS Microbiol Lett 155 147— 153, 1997. 

Genetic factors influence the rate of not only synthesis of proteins but also their breakdown, i.e., the rate of turnover. As we have seen in Chapter 10, some enzymes are synthesized as inactive proenzymes which are later modified to active forms, and active enzymes are destroyed, both by accident and via deliberate hydrolytic pathways. Protein antienzymes may not only inhibit enzymes but may promote their breakdown.35 An example is the antienzyme that controls ornithine decarboxylase, a key enzyme in the synthesis of the polyamines that are essential to growth.36,37 As with all cell constituents, the synthesis of enzymes and other proteins is balanced by degradation. 

Douki T, Bretonniere Y, Cadet J (2000) Protection against radiation-induced degradation of DNA bases by polyamines. Radiat Res 153 29-35... 

Raaphorst GP, Azzam El (1981) Fixation of potentially lethal radiation damage in Chinese hamster cells by anisotonic solutions, polyamines, and DMSO. Radiat Res 86 52-66 Rabow L, Stubbe J, Kozarich JW, Gerlt JA (1986) Identification of the alkaline-labile product accompanying cytosine release during bleomycin-mediated degradation of d(CGCGCG). J Am Chem Soc 108 7130-7131... 

Najm I., el-Skaf G., Massicotte G., Vanderklish P, Lynch G., and Baudry M. (1992). Changes in polyamine levels and spectrin degradation following kainate-induced seizure activity effect of difluoromethylomithine. Exp. Neurol. 116 345-354. 

Fig. 1 Proposed mechanism of gene transfection [117]. (1) Formation of the DNA/polymer complex (polyplex), (2) endocytosis of the polyplex, (3) fusion of endosome and lysosome, (4) release of the polyplex into the cytosol, (5a) incorporation of the polyplex into the nucleus, (5b) release of the siRNA into the cytosol, (6) transcription of the DNA into mRNA followed by release of the polyamine back into the cytosol, (7a) translation of mRNA, and (7b) mRNA degradation. The metabolism of the polyamine is still unclear. Reproduced with permission from [117]. Copyright 2002 Elsevier...

Kloeckner J, Wagner E, Ogris M (2006) Degradable gene carriers based on oligomerized polyamines. Eur J Pharm Sci 29 414-425... 

DNA has been embedded in LbL films by assembling with polycations like PLL, polyethyleneimine (PEI), and poly(dimethyldiallylammonium chloride) (PDAD) [38-42]. Zhang showed that the DNA released from the film with synthetic degradable polyamine is transcriptionally viable [41]. DNA molecules can keep their structure when incorporated in the film with synthetic polymers [39], making films with DNA suitable candidates for gene delivery. 

In summary, NEM-induced nociceptive behavior may be mediated through inhibition of the degradation of endogenous dynorphins, presumably big dynorphin that in turn activates the NMDA receptor ion-channel complex by acting on the polyamine recognition site (Fig. 2). 

Precursors of /1-alanine 3 biosynthesis are uracil 2, L-aspartate 4, and polyamines which are subjected to degradation in distinct ways - whereas uracil is metabolized by hydrogenation followed by hydrolysis, polyamines like spermine 1 are oxidized and L-aspartate is decarboxylated (Scheme 1.6.1). 

In the analysis of H-NMR spectra of compounds elaborated from aliphatic fatty acids and polyamines it is rather difficult to determine the linear or branched nature of the fatty acid. In order to differentiate, well-known oxidative degradation reactions (e.g., HN03) are recommended in addition to spectroscopic methods. 

Some structure elucidation methods often have been used in the past and should also be recommended for future use. The Hofmann degradation is one of these reactions another is the use of a KOH melt to hydrolyze (amide) bonds. This method is well-known for determining the nature of the polyamine. One must keep in mind, however, that in addition to the cleavage of polyamine substituent bonds, the polyamines themselves are degraded, and smaller amino fragments can be detected. Therefore, a careful analysis of the product is necessary. 

Polyamine oxidase is a flavin-dependent peroxisomal enzyme involved in the degradation of polyamines to putrescine. This assay measures the conversion of /V -acetylspermidine to putrescine. 

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