Peptide siderophores

Abstract

Siderophores are low molecular weight iron chelators, produced by virtually all bacteria, fungi and some plants. They serve to deliver the essential element iron, barely soluble under aerobic conditions, into microbial cells. Siderophores are therefore important secondary metabolites which are very often based on amino acids and their derivatives. Biosynthesis, transport, regulation and chemical synthesis of natural siderophores and their analogues is of considerable interest for the protein and peptide chemist. This review gives an overview of the structural classes of peptidic siderophores, along with data on their biosynthesis. On a number of representative examples, strategies and schemes of their chemical synthesis are described.

Rapid identification of siderophores by combined thin‐layer chromatography/matrix‐assisted laser desorption/ionization mass spectrometry

“…1(a)). It is found in many enterobacteriaceae ,6 after being first isolated from Escherichia coli 31. Ferrioxamine B is a trihydroxamate‐containing siderophore produced by Streptomyces and Nocardia spp.…”

“…The members of the ferrichrome family, ferrichrome and ferrirhodin, are fungal trihydroxamate siderophores (Figs. 1(c) and 1(d)) 6. Coprogens are a group of fungal trihydroxamate siderophores containing diketopiperazine rings (Fig.…”

“…Coprogens are a group of fungal trihydroxamate siderophores containing diketopiperazine rings (Fig. 1(e)) 6. The diketopiperazine ring is also present in the structurally related rhodotorulic acid (Fig.…”

Both metal-chelating and free radical-scavenging synthetic pentapeptides as efficient inhibitors of reactive oxygen species generation

“…4a). 55 With increasing pH, the CD spectra indicated considerable changes compared to the free peptide, the intensity of the charge transfer band diminished with the deprotonation of coordinated water molecules (Fig. S2, right, ESI †).…”

Iron behaving badly: inappropriate iron chelation as a major contributor to the aetiology of vascular and other progressive inflammatory and degenerative diseases

“…Generally, the harder ligands that favour Fe(III) involve O whereas softer ligands that bind Fe(II) involve N and S. The type of ligand also influences the absorption spectrum of the ferric form of the chelator, such that conclusions can be drawn about the types of group involved in the complex. These charge transfer bands that appear on ligand binding are at around 340 nm for carboxylates, around 425 nm for trishydroxamates, 470 nm for bis-hydroxamates, 515 nm for monohydroxamates, around 480 nm for tris-catecholates, 560 nm for bis-catecholates and 680 nm for mono-catecholates [ 173 ]. In addition, for tris-bidentate complexes the complex can, on an octahedral arrangement, have two different configurations, a left-handed propeller, termed the Λ-configuration, and a righthanded propeller, the Δ-configuration [ 173 ].…”