Reducing the concentration of polyamines (spermine, spermidine, and putrescine) in the body pool may slow the cancer process. Because dietary spermine, spermidine, and putrescine contribute to the body pool of polyamines, quantifying them in the diet is important. Limited information about polyamine content of food is available, especially for diets in the United States. This brief report descr...

The crystal structure of the title compound, [Ni(C8H20N4)(C12H8N2)](ClO4)2, has been determined by X-ray diffraction. The Ni(II) ion is six coordinated with four nitrogen atoms of the tetradentate macrocyclic ligand and two nitrogen atoms of the bidentate ligand in a distorted octahedron geometry. The folded tetradentate macrocyclic ligand adopts a configuration having four five-membered chelat...

Two thread-shaped cations, pyridinium nicotinamide and imidazolium, as their chloride and hexafluorophosphate salts, were studied with regards to complexation with hydrogen-bond-donating acyclic and macrocyclic ligands. In the latter case, the cations form pseudorotaxanes templated by the chloride anion but not hexafluorophosphate. This formation is a function of the coupling of ion-pairing bet...

IRK1 (Kir2.1) inward-rectifier K+ channels exhibit exceedingly steep rectification, which reflects strong voltage dependence of channel block by intracellular cations such as the polyamine spermine. On the basis of studies of IRK1 block by various amine blockers, it was proposed that the observed voltage dependence (valence approximately 5) of IRK1 block by spermine results primarily from K+ io...

Acetylpolyamine and spermine oxidases are involved in the catabolism of polyamines. The discovery of selective inhibitors of these enzymes represents an important tool for the development of novel anti-neoplastic drugs. Here, a comparative study on acetylpolyamine and spermine oxidases inhibition by the polyamine analogue chlorhexidine is reported. Chlorhexidine is an antiseptic diamide, common...

Polyamines play a regulatory role in eukaryotic cell growth and morphogenesis. Despite many molecular advances, the underlying mechanism of action remains unclear. Here, we investigate a mechanism by which spermine affects the morphogenesis of a dimorphic fungal model of emerging relevance in plant interactions, Yarrowia lipolytica, through the recruitment of a phytohormone-like pathway involvi...

Steeply voltage-dependent block by intracellular polyamines underlies the strong inward rectification properties of Kir2.1 and other Kir channels. Mutagenesis studies have identified several negatively charged pore-lining residues (D172, E224, and E299, in Kir2.1) in the inner cavity and cytoplasmic domain as determinants of the properties of spermine block. Recent crystallographic determinatio...