Spermidine synthesis

Arginine is the formamidine donor for creatine synthesis (Figure 31-6) and via ornithine to putrescine, spermine, and spermidine (Figure 31-3) Arginine is also the precursor of the intercellular signaling molecule ni-... 

After 2 h incubation of the prepared antibody beads with UV-crosslinked extract in a cold room, the beads are washed 4 x with 100 /A RIPA buffer (50 mMTris-HCl pH 7.5, 150 rnMNaCl, 1% NP-40, 0.5% sodium deoxycholate, and 0.1% SDS) and lx with genomic DNA lysis buffer (50 mM Tris, pH 7.4, 10 mM EDTA, 500 mM NaCl, 2.5 mM DTT, 0.5 mM spermidine, 1% Triton X-100). Approximately 300 /(I of PK solution (1 mg/ml proteinase K in genomic DNA lysis buffer and 0.2 U//A RNase inhibitor) is added to the total lysate previously kept on ice and the beads are then incubated at 37° for 30 min. Gently flick the tubes to resuspend the beads every 10 min during the incubation. After removal of the proteinase K solution, 300 /A of RNA extraction solution (4 M guanidine thiocyanate, 0.5% sarkosyl, and 25 mM sodium citrate, pH7) is added to the beads, incubated for 10 min and the supernatant is mixed with 30 fig yeast tRNA (as a carrier) and 30 fil of 3 M sodium acetate. The RNA solution is phenol-chloroform extracted, ethanol-precipitated, and the pellet washed once with 70% ethanol. The dry pellet is used for 1st strand cDNA synthesis, followed by PCR analysis. The removal of proteins... 

Pistillarin was first isolated from Clavariadelphus pistillaris and from several Ramaria spp. (Basidiomycetes) 334). Recently, it was found to be produced also by the marine fungus Penicillium bilaii 56). Like siderochrome II below it is a spermidine derivative substimted only at the terminal NHa-groups (A, iV °-di-(3,4-dihydroxy)benzoyl-spermidine). Its synthesis and that of siderochrome II was reported, their siderophore activity and their complexation with Fe (1 1 complexes) was investigated 102, 299). A derivative of pistillarin substituted at aU three amino functions has not been reported yet. 

Nagao Y, Miyasaka T, Hagiwara Y, Fujita E 1984 Total Synthesis of Parabactin, a Spermidine Siderophore. J Chem Soc Perkin Trans I 183... 

Figure 11.9 Schematic view of the experimental strategy for carrying out poly(Phe) synthesis in POPC liposomes, (i) Freeze-thaw (x 7) solution containing t-RNAP , poly(U), Phe, ATP, GTP, Mg(OAc)2, NH4CI, spermine, spermidine, phos-phoenolpyruvate. (ii) Soution containing pyruvate kinase, 100 000 g supernatant enzymes, 308 and SOS ribosomal subunits, (iii) 1. Free-thaw (x3) 2. Brief extrusion 3. Addition of EDTA (final concentration = 35 mM. (iv) Withdrawl of aliquots at indicated time and cold TCA precipitation. Analysis of the radioactivity remaining on the glass filter by p-scintillation counting. (Modified from Oberholzer et al, 1999.)...

Fillingame, R. H., Jorstad, C. M., and Morris, D. R. (1975). Increased cellular levels of spermidine or spermine are required for optimal DNA synthesis in lymphocytes activated by concanavalin A. Proc. Natl. Acad. Sci. U.S.A. 72, 4042-4045. 

Many studies on the cationic trypanocides have failed to identify their site(s) of action. A recent proposal is that their activity is due to interaction with biologically active polyamines, e.g. spermine and spermidine (80MI10809). These and other polyamines have significant roles in cell division and macromolecular synthesis. 

Ornithine decarboxylase is specifically inhibited by the enzyme-activated inhibitor a-difluoromethyl-ornithine, which can cure human infection with Trypanosoma brucei (African sleeping sickness) by interfering with polyamine synthesis.243-2443 In combination with inhibitors of spermidine synthase or S-adenosylmethionine decarboxylase,245 it can reduce polyamine levels and growth rates of cells. Another powerful inhibitor that acts on both ornithine and adenosylmethionine decarboxylases is the hydroxy-lamine derivative l-aminooxy-3-aminopropane 246... 

Hypusine (Ne-(4-amino-2-hydroxybutyl)lysine)242 occurs in mammalian initiation factor 4D, which is utilized in protein synthesis (Chapter 29) and is formed by transfer of the 4-carbon butylamine group from spermidine to a lysine side chain followed by hydroxylation 280 2823 The lupine alkaloid lupinine283 is formed from two C5 units of cadaverine which arises by decarboxylation of lysine. Silaffins (pp. 178, 1381) also contain modified lysines. 

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... 

Polyamines like spermidine and spermine, which bind tightly to nucleic acids and are abundant in rapidly proliferating cells, are present in parasitic helminths in amounts comparable to those in vertebrate cells. As the enzymes necessary for their synthesis are lacking in adult parasitic flatworms, it is assumed that these compounds are obtained from the host (Bacchi and Yarlett, 1 995). In F. hepatica a polyamine N-acetyltransferase has been characterized, that is thought to play a major role in the polyamine metabolism of this parasite by inactivating excess amines (Aisien and Walter, 1993). 

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). 

This cyclization has been used for synthesis of four spermidine alkaloids, such as celacinnine (4). 

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