Iron is an essential nutrient that facilitates cell proliferation and growth, which plays a pivotal role in modulating the battle for survival between mammalian hosts and their pathogens. Pathogenic bacteria secrete siderophores to acquire iron from the host. However, lipocalin 2 (Lcn2), a siderophore-binding antimicrobial protein, binds to siderophores to prevent bacterial uptake of iron, whic...

Most bacterial pathogens require iron to grow and colonize host tissues. The Gram-negative bacterium Salmonella enterica serovar Typhimurium causes a natural systemic infection of mice that models acute and chronic human typhoid fever. S. Typhimurium resides in tissues within cells of the monocyte lineage, which limit pathogen access to iron, a mechanism of nutritional immunity. The primary fer...

The molecular mechanisms that define asymptomatic bacteriuria (ABU) Escherichia coli colonization of the human urinary tract remain to be properly elucidated. Here, we utilize ABU E. coli strain 83972 as a model to dissect the contribution of siderophores to iron acquisition, growth, fitness, and colonization of the urinary tract. We show that E. coli 83972 produces enterobactin, salmochelin, a...

The uptake of iron into Pseudomonas aeruginosa is mediated by two major siderophores produced by the bacterium, pyoverdine and pyochelin. The bacterium is also able of utilize several heterologous siderophores of bacterial or fungal origin. In this work, we have investigated the iron uptake in P. aeruginosa PAO1 by the heterologous ferrichrome siderophore. (55)Fe uptake assays showed that ferri...

The highly active extracellular siderophores previously detected in young cultures of Aspergillus nidulans and Penicillium chrysogenum have been identified as the cyclic ester fusigen (fusarinine C), and its open-chain form, fusigen B (fusarinine B).

Novel citrate-hydroxamate siderophores, named nannochelins A, B and C, were isolated from the culture broth of the myxobacterium Nannocystis exedens strain Na e485. The new substances showed weak growth-inhibitory activity against some bacteria and fungi.