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Spermidine reactions

Translation reaction mixture contained 20 % (v/v) wheat germ extract and the followings (final concentrations) 60 mM HEPES/KOH (pH 7.6), 1 mM ATP, 100 pM GTP, 300 pM spermidine, 2 mM magnesium acetate, 40 mM potassium acetate, 160 pM each... [Pg.170]

Qualitatively, the results observed with ferric chloride and lead acetate were highly variable. It was first noted with ferric chloride that gels were forming within the reaction vessel We observed the formation of translucent gels in the reaction vessel with calcium chloride, spermidine and ferric chloride. In the case of lead acetate, a feathery type precipitate formed in the reaction vessel. Macdonald et al. (14) observed formation of a clear gel and flocculated precipitate in high ester pectin treated with lemon endocarp and peel PE isozymes, respectively. They hypothesized that the different gel structures were due to unique mechanism of deesterification by the PE isozymes. Our results with different cations and formation of different gel structure or precipitate seems to be similar to that reported by Macdonald et al. (14). If there is a different mechanism of de-esterification for plant PEs,... [Pg.477]

Figure 9 summarizes the electrode responses toward a variety of DNA-binding substrates [14c]. For intercalators (quinacrine, acridine orange, and safranin) and groove binders (spermine and spermidine), a steep rise followed by a saturation of the concentration response curve is commonly observed. If one compares the specific concentration which gives a 50% response in the increment of the cathodic peak current (A/p ) for each substrate, a selectivity order of quinacrine acridine orange > spermine > spermidine > safranin can be estimated. The binding constants measured in aqueous media for the affinity reaction with ds DNA are as follows quinacrine, 1.5 x 10 (38 mM NaCl)... [Pg.526]

Kamei et al. [45] separated spermine, spermidine, putrescine, and cadav-erine in an ion-pair reversed-phase LC system and detected the hydrogen peroxide formed in the reaction catalyzed by the enzymes putrescine oxidase and polyamine oxidase with POCL. The same analytes were determined in a later study [46], together with the acetyl derivatives. The sensitive determination of uric acid, selectively converted to hydrogen peroxide by uricase, has been investigated by several authors [37, 47],... [Pg.158]

The venoms of many kinds of bees, wasps, and hornets (the genera Vespa, Polistes, Vespula, Ropalidia, etc.) contain biogenic amines such as histamine (136), serotonin (141), and catecholamines in addition to polyamines such as putrescine (111), spermidine (110), and spermine (112) (Table VIII). The biogenic amines in the venoms act as the main pain-producing principles 46). The contents of these amines in the venom may affect the severity of pain production, edematous reaction of the skin, or increase in skin permeability by stings of these insects. Consequently these amines act as toxins for their defense, together with acetylcholine, enzymes, and peptides 47). [Pg.198]

A mixture of 1 (200 mg, 0.45 mmol) and spermidine 4b (380 mg, 1.1 mmol) in THE (10 mL) was reacted with NaBH(OEh)3 (2 equiv) at room temperature under an argon atmosphere. The reaction was monitored by TLC analysis. After the reaction was complete, the solvent was removed, the residue extracted with ethyl acetate, and then the combined organic extracts were dried over anhydrous Na2S04, before being concentrated. [Pg.180]

The yield of in vitro synthesis of RNA from 2 -modified nucleotides is decreased 2-100-fold, compared to the reaction with unmodified nucleotides [32]. Various transcription buffers are reported to enhance the transcription by T7 RNA polymerase using 2 -modified pyrimidine nucleotides [28, 33]. These buffers mostly contain higher spermidine concentrations and additives like PEG or Triton. Additionally, the concentration of T7 RNA polymerase should be increased to improve... [Pg.75]

Macroheterocyclization.1 s Pd(0) can catalyze macrocyclizations which form a C—N bond. This reaction was used in a synthesis of the spermidine alkaloid inandenine-12-one (1). [Pg.260]

A third biosynthetic pathway to /-alanine 3 by oxidation of spermidine 13 and spermine 1 has been recently elucidated in yeast [17]. This reaction starts by transformation of L-methionine 15 to decarboxyadenosylmethionine (dcAdoMet, 16). The latter alkylates putrescine 12 at one or both nitrogens generating spermidine 13 and spermine 1 which are oxidized to 3-aminopropanal 14 and further to /-alanine (Scheme 1.6.4). [Pg.92]

In the course of the structure elucidation of the natural occurring spermidine alkaloides such as inandeninone 11/108, (Scheme 11/15) the Schmidt reaction played an important role. The alkaloid is a nearly 1 1 mixture of two isomers, isolated from Oncinotis inandensis Wood et Evans. To make sure that the compounds differed only in the location of the carbonyl group at positions C(12) and C(13), the mixture was treated with sodium azide, sulfuric acid, and chloroform. The product consisted of a mixture of four ring enlarged dilactams (one of them, compound 11/109, is shown) with nearly equal ratios [84],... [Pg.21]

The transamidation reaction has been successfully applied to the syntheses of a number of natural polyamino alkaloids. These alkaloids contain principally spermidine or spermine as the basic skeleton [37],... [Pg.105]

This triamine contains a spermidine backbone, but in contrast to the examples given above for the Zip reaction, the side chain in VI/54is a 1,4-diaminobutane. Ring enlargement via a seven-membered intermediate must be done with a base... [Pg.107]

The structure elucidation of 34 was based, in principle, on two facts color reactions and hydrolysis. Compound 34 does not react with ninhydrin (therefore, no primary amino group is present) but it does react with l-fluoro-2,4-dinitrobenzene. By exact determination of the absorption ratio E35O/E390 after the reaction with the latter reagent, Tait concluded that 34 contains a secondary amino group (50). Hydrolysis (6 N HC1, 110°C, 24 hr) of the so-called compound II afforded 2,3-dihydroxybenzoic acid and spermidine (50). The presence of two 2,3-dihydroxybenzoyl residues in 34 was demonstrated by its enzymatic (50) and chemical synthesis (51-54). [Pg.98]

The presence of spermidine in the inandenines has been proved by KOH fusion The reaction product has been identified as the triacetyl derivative of spermidine. The mass spectrum of the triacetyldeoxo compounds 61 and 62 shows how spermidine is incorporated in the alkaloids. This mixture of compounds was prepared by reduction of 53/54 with LAH followed by acetylation. The base peak at [M+ — 100] in the mass spectrum is formed by a cleavage with respect to N-l, between C-l and C-2. If the alternative incorporation [e.g., as in the case of neooncinotine (41)] had occurred, a cleavage of 86 atomic mass units from the molecular ion could be expected. [Pg.106]

Scheme 15. Protection of the ketone and transformation of the methyl esters to the activated amides in 102 yielded 103. The condensation reaction between the two primary amino groups of spermidine and 103 was achieved by using high-dilution techniques. The incorporation of the unsymmetric spermidine took place in both ways so that a nearly 1 1 mixture of ( )-lun-arine (91) and ( )-lunaridine (96) was formed. Scheme 15. Protection of the ketone and transformation of the methyl esters to the activated amides in 102 yielded 103. The condensation reaction between the two primary amino groups of spermidine and 103 was achieved by using high-dilution techniques. The incorporation of the unsymmetric spermidine took place in both ways so that a nearly 1 1 mixture of ( )-lun-arine (91) and ( )-lunaridine (96) was formed.

See other pages where Spermidine reactions is mentioned: [Pg.532]    [Pg.532]    [Pg.532]    [Pg.532]    [Pg.330]    [Pg.163]    [Pg.125]    [Pg.226]    [Pg.527]    [Pg.266]    [Pg.281]    [Pg.675]    [Pg.1078]    [Pg.1079]    [Pg.1083]    [Pg.28]    [Pg.353]    [Pg.26]    [Pg.172]    [Pg.1097]    [Pg.114]    [Pg.129]    [Pg.408]    [Pg.409]    [Pg.413]    [Pg.570]    [Pg.34]    [Pg.113]    [Pg.17]    [Pg.26]    [Pg.143]    [Pg.547]    [Pg.240]    [Pg.162]    [Pg.101]    [Pg.102]   
See also in sourсe #XX -- [ Pg.819 , Pg.826 ]




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Spermidine

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