Bacterial siderophores: diversity, uptake pathways and applications.

Iron is an essential nutrient for the growth, survival and virulence of almost all bacteria. To access iron, many bacteria produce siderophores, molecules with a high affinity for iron. Research has highlighted substantial diversity in the chemical structure of siderophores produced by bacteria, as well as remarkable variety in the molecular mechanisms involved in strategies for acquiring iron through these molecules.

The role of FoxA, FiuA, and FpvB in iron acquisition via hydroxamate-type siderophores in Pseudomonas aeruginosa.

Siderophores are specialized molecules produced by bacteria and fungi to scavenge iron, a crucial nutrient for growth and metabolism. Catecholate-type siderophores are mainly produced by bacteria, while hydroxamates are mostly from fungi. This study investigates the capacity of nine hydroxamate-type siderophores from fungi and Streptomyces to facilitate iron acquisition by the human pathogen Pseudomonas aeruginosa.

PvdL Orchestrates the Assembly of the Nonribosomal Peptide Synthetases Involved in Pyoverdine Biosynthesis in .

The pyoverdine siderophore is produced by to access iron. Its synthesis involves the complex coordination of four nonribosomal peptide synthetases (NRPSs), which are responsible for assembling the pyoverdine peptide backbone. The precise cellular organization of these NRPSs and their mechanisms of interaction remain unclear.

Experimental and computational methods to highlight behavioural variations in TonB-dependent transporter expression in Pseudomonas aeruginosa versus siderophore concentration.

Iron is a key nutrient for bacterial growth. The source can be either heme or siderophore-Fe complexes. Siderophores are small molecules synthesized by bacteria to scavenge iron from the bacterial environment.

Siderophore specificities of the Pseudomonas aeruginosa TonB-dependent transporters ChtA and ActA.

Iron is an essential nutrient for the survival and virulence of Pseudomonas aeruginosa. The pathogen expresses at least 15 different iron-uptake pathways, the majority involving small iron chelators called siderophores. P.

Vectorization via Siderophores Increases Antibacterial Activity of K(RW) Peptides against Pseudomonas aeruginosa.

A series of new conjugates comprised from a small synthetic antimicrobial peptide (AMP) and a siderophore-type vector component was designed and tested for activity on P. aeruginosa PAO1 and several genetically modified strains. As AMP, the well-established arginine-tryptophane combination K(RW) (P1) was chosen with an added lysine for siderophore attachment.

Improved engineering of Pseudomonas aeruginosa to study the adaptation of pyoverdine production under intra- or inter- specific bacterial competition.

Pseudomonas aeruginosa (PA) is a common cause of chronic infections, particularly feared by cystic fibrosis patients. PA colonizes the lung where it adapts to the local environment, and/or to treatments by drugs. This genotypic and phenotypic adaptation, in turns, influences its interaction with its environment, like bacteria from the microbiota.

Pseudomonas aeruginosa and its multiple strategies to access iron.

Pseudomonas aeruginosa is a ubiquitous bacterium found in many natural and man-made environments. It is also a pathogen for plants, animals, and humans. As for almost all living organisms, iron is an essential nutrient for the growth of P.

Hijacking of the Enterobactin Pathway by a Synthetic Catechol Vector Designed for Oxazolidinone Antibiotic Delivery in .

Enterobactin (ENT) is a tris-catechol siderophore used to acquire iron by multiple bacterial species. These ENT-dependent iron uptake systems have often been considered as potential gates in the bacterial envelope through which one can shuttle antibiotics (Trojan horse strategy). In practice, siderophore analogues containing catechol moieties have shown promise as vectors to which antibiotics may be attached.

Plant-Derived Catechols Are Substrates of TonB-Dependent Transporters and Sensitize Pseudomonas aeruginosa to Siderophore-Drug Conjugates.

Pseudomonas aeruginosa is an opportunistic pathogen responsible for acute and chronic infections in immunocompromised hosts. This organism is known to compete efficiently against coinfecting microorganisms, due in part to the secretion of antimicrobial molecules and the synthesis of siderophore molecules with high affinity for iron. P.

Uptake Mechanisms and Regulatory Responses to MECAM- and DOTAM-Based Artificial Siderophores and Their Antibiotic Conjugates in .

The development of new antibiotics against Gram-negative bacteria has to deal with the low permeability of the outer membrane. This obstacle can be overcome by utilizing siderophore-dependent iron uptake pathways as entrance routes for antibiotic uptake. Iron-chelating siderophores are actively imported by bacteria, and their conjugation to antibiotics allows smuggling the latter into bacterial cells.

Past mastering of metal transformation enabled physicians to increase their therapeutic potential.

Background: Metals are trace elements, vital in some instances or toxic in others. Due to this toxicity, they have been used since ancient time as antimicrobials, and prescribed when plant-only remedies were not efficient enough. These remedies could still contain secrets that may lead to the discovery of new therapeutically interesting combinations.

How the Presence of Hemin Affects the Expression of the Different Iron Uptake Pathways in Cells.

Iron is an essential nutriment for almost all organisms, but this metal is poorly bioavailable. During infection, bacteria access iron from the host by importing either iron or heme. , a gram-negative pathogen, secretes two siderophores, pyoverdine (PVD) and pyochelin (PCH), to access iron and is also able to use many siderophores produced by other microorganisms (called xenosiderophores).

A role for PchHI as the ABC transporter in iron acquisition by the siderophore pyochelin in Pseudomonas aeruginosa.

Iron is an essential nutrient for bacterial growth but poorly bioavailable. Bacteria scavenge ferric iron by synthesizing and secreting siderophores, small compounds with a high affinity for iron. Pyochelin (PCH) is one of the two siderophores produced by the opportunistic pathogen Pseudomonas aeruginosa.

Structural insights into a novel family of integral membrane siderophore reductases.

Gram-negative bacteria take up the essential ion Fe as ferric-siderophore complexes through their outer membrane using TonB-dependent transporters. However, the subsequent route through the inner membrane differs across many bacterial species and siderophore chemistries and is not understood in detail. Here, we report the crystal structure of the inner membrane protein FoxB (from ) that is involved in Fe-siderophore uptake.

The Esterase PfeE, the Achilles' Heel in the Battle for Iron between and .

Bacteria access iron, a key nutrient, by producing siderophores or using siderophores produced by other microorganisms. The pathogen produces two siderophores but is also able to pirate enterobactin (ENT), the siderophore produced by . ENT-Fe complexes are imported across the outer membrane of by the two outer membrane transporters PfeA and PirA.

1,2,3-Triazole-gold(I)-triethylposphine derivatives active against resistant Gram-positive pathogens.

Innovative organogold(I) antibacterial compounds were synthesized by click chemistry with triethylphosphine-gold(I) azides and an alkyne derivative. The resulting organo-gold(I) compounds exhibit high levels of antibacterial activity against Gram-positive pathogens, with particularly low MICs against Clostridium difficile.

The pathogen optimizes the production of the siderophore pyochelin upon environmental challenges.

Siderophores are iron chelators produced by bacteria to access iron, an essential nutrient. The pathogen Pseudomonas aeruginosa produces two siderophores, pyoverdine and pyochelin, the former with a high affinity for iron and the latter with a lower affinity. Furthermore, the production of both siderophores involves a positive auto-regulatory loop: the presence of the ferri-siderophore complex is essential for their large production.

Opportunistic use of catecholamine neurotransmitters as siderophores to access iron by Pseudomonas aeruginosa.

Iron is an essential nutrient for bacterial growth and the cause of a fierce battle between the pathogen and host during infection. Bacteria have developed several strategies to access iron from the host, the most common being the production of siderophores, small iron-chelating molecules secreted into the bacterial environment. The opportunist pathogen Pseudomonas aeruginosa produces two siderophores, pyoverdine and pyochelin, and is also able to use a wide panoply of xenosiderophores, siderophores produced by other microorganisms.

Identification of the fatty acid coenzyme-A ligase FadD1 as an interacting partner of FptX in the Pseudomonas aeruginosa pyochelin pathway.

Pseudomonas aeruginosa is one of the most important nosocomial bacteria emerging as a highly multidrug-resistant pathogen. P. aeruginosa produces two siderophores including pyochelin (PCH) to fulfil its need for iron during infections.

Phenotypic Adaptation of in the Presence of Siderophore-Antibiotic Conjugates during Epithelial Cell Infection.

Iron acquisition pathways have often been considered to be gateways for the uptake of antibiotics into bacteria. Bacteria excrete chelators, called siderophores, to access iron. Antibiotic molecules can be covalently attached to siderophores for their transport into pathogens during the iron-uptake process.

FLIM-FRET Measurements of Protein-Protein Interactions in Live Bacteria.

Protein-protein interactions (PPIs) control various key processes in cells. Fluorescence lifetime imaging microscopy (FLIM) combined with Förster resonance energy transfer (FRET) provide accurate information about PPIs in live cells. FLIM-FRET relies on measuring the fluorescence lifetime decay of a FRET donor at each pixel of the FLIM image, providing quantitative and accurate information about PPIs and their spatial cellular organizations.

Nocardamine-Dependent Iron Uptake in : Exclusive Involvement of the FoxA Outer Membrane Transporter.

Iron is a key nutrient for almost all living organisms. Paradoxically, it is poorly soluble and consequently poorly bioavailable. Bacteria have thus developed multiple strategies to access this metal.