Siderophore-redox active ionophore host-guest assemblies: A prototype for selective metal ion compartmentalization

Chemical and Biological Aspects of Nutritional Immunity—Perspectives for New Anti‐Infectives that Target Iron Uptake Systems

“…Complex 82 was compared with the corresponding host-guest assemblies derived from lasalocid A( 79)a nd ferrioxamine B. [150,151] Carrier-facilitated bulk liquid membrane transport of the Fe 3+ siderophore was indeed achieved. [152,153] On the basis of this precedent, Orcutt and Wells developed liposomes containing 80 in the bilayer membrane, which selectively recognized and extracted FeHDFB + preferably from the surrounding aqueous phase with respect to Ca 2+ ,Na + ,and K + .…”

“…The corresponding Fe 3+ complex ferrioxamine B (FeHDFB + ) forms a ternary second sphere complex 82 with the lariat ether through the terminal ammonium unit, while the carboxylate arm further contributes to the complex stability through electrostatic interactions (Figure ). Complex 82 was compared with the corresponding host–guest assemblies derived from lasalocid A ( 79 ) and ferrioxamine B . Carrier‐facilitated bulk liquid membrane transport of the Fe 3+ siderophore was indeed achieved .…”

Voltammetric Investigation of Iron(III) Interactions with Phytate

“…In the nature microorganisms produce low molecular ligands (siderophores) with high affinity to form soluble chelates with Fe(III) ions, to acquire ferric iron from the environment and to assure transport inside of the living organisms [1,3,4]. Coordination of iron(III) and iron(II) with ligands (L) is directly related to the redox potential of Fe(III)/Fe(II) couple corresponding to the quotient between stability constant K III (Fe(III)L)/K II (Fe(II)L).…”

“…Owing to this, voltammetry 5 is ideally suited for studies of metal to ligand interactions and has been used successfully in the past, e.g. for investigation of iron(III) and iron(II) complexes with biologically important low molecular ligands such as citrate, tartrate, oxalate [29][30][31], and siderophores [3,4,32]. According to our knowledge only Torres et al [24] applied cyclic voltammetry (CV) on the glassy carbon and gold electrode for the evaluation of the Fe(III)/Fe(II) redox response in the presence of phytate.…”

Chemische und biologische Aspekte von “Nutritional Immunity” – Perspektiven für neue Antiinfektiva mit Fokus auf bakterielle Eisenaufnahmesysteme

“…[149] Der entsprechende Fe 3+ -Komplex Ferrioxamin B(FeHDFB + )b ildet den ternären Komplex 82 mit dem Lariatether über die terminale Ammoniumgruppe, während der Carboxylatarm über elektrostatische Wechselwirkungen zur Komplexstabilitätbeiträgt (Abbildung 24). 82 wurde mit der entsprechenden Wirt-Gast-Gruppe aus Lasalocid A( 79)u nd Ferrioxamin B [150,151] verglichen. Ein durch den Träger erleichterter Tr ansport des Fe 3+ -Siderophors durch die Membran wurde erreicht.…”