Physiology of Moss-Bacterial Associations
R. N. Chopra, Satish C. Bhatla in Bryophyte Development: Physiology and Biochemistry, 2019
The possibility that the growth-promoting effects of some bacteria depend on production of iron-chelating siderophores has been investigated. The Pseudomonas fluorescens-putida group is often used as an inoculant on crop plants because it increases yields by antagonizing deleterious fungi and bacteria. The production of siderophores which reduce the available iron for growth of the harmful organisms appears necessary for this response.28,29 The increase in plant growth by root-colonizing fluorescent pseudomonads in the rhizosphere is also thought to be due to siderophore production under iron-limiting conditions.30 Evidence that supports this hypothesis includes the observation that addition of iron abolishes the effect, siderophore-negative mutants do not promote growth, and addition of siderophores promotes growth. The promotion of growth and suppression of inhibition also may be due to competition for carbon compounds or the production of hormones, antibiotics, or bacteriocins.29
Inflammation and Infection
Karl H. Pang, Nadir I. Osman, James W.F. Catto, Christopher R. Chapple in Basic Urological Sciences, 2021
P. mirabilis urease is expressed during growth in urine:Hydrolysis of urea to carbon dioxide and ammonia.Creates alkaline urine → calcium crystal (apatite) formation and magnesium ammonium phosphate precipitates (struvite)Crystals become trapped within polysaccharides produced by attached bacterial cells → crystalline biofilms on tissues/cathetersAmmonia is toxic to urothelial cells.The urinary tract is limited in iron (an essential element for bacterial growth).Uropathogens synthesise siderophores to scavenge, chelate, and transport iron (Fe3+).Siderophores synthesised include the proteins aerobactin, yersiniabactin, and enterobactin.
Role of Bacteria in Dermatological Infections
K. Balamurugan, U. Prithika in Pocket Guide to Bacterial Infections, 2019
However, C. jeikeium is capable of developing papular eruptions in patients who are immunocompromised and individuals with skin abrasions or traumas. C. jeikeium harbors numerous virulence traits such as siderophores, invasins, adhesins, biofilm formation, and superoxide dismutase (Joh et al., 1999; Ton-That and Schneewind, 2004; Blaise et al., 2008). The siderophores mediates iron and manganese sequestration and helps to evade host attack by surviving superoxide radicals. Adhesins and invasins promote the virulence by aiding adhesion to host epithelium and host invasion. Also, the cell envelope of C. jeikeium contains corynomycolic acid, which helps it to resist multiple antibiotic treatments (Cogen et al., 2008).
Potential of Application of Iron Chelating Agents in Ophthalmic Diseases
Published in Seminars in Ophthalmology, 2021
Alireza Ghaffarieh, Joseph B. Ciolino
Siderophores are essential biomolecules for the growth and proliferation of both pathogenic and non-pathogenic microbes, and their synthesis is a target for the production of new antimicrobial pharmaceuticals. The major classes of siderophores are the hydroxamate siderophores (e.g. Desferrioxamine), which are found in fungi, and the catechol siderophores (e.g. enterobactin), which are found in bacteria.30 The iron chelating proteins transferrin and lactoferrin have been involved in the uptake and transfer of iron in mammalian cells via specific pathways, preventing microbial pathogens from accessing iron. As a result, they prevent or inhibit the growth and proliferation of pathogenic organisms in mammals.31 Many chelators, especially chelating drugs, were designed based on siderophore prototypes. All the iron chelating drugs, dietary molecules and other drugs with chelating properties, such as the tetracyclines, anthracyclines, salicylates, hydroxyurea, etc., can affect iron uptake by microbial pathogens and can accordingly inhibit or promote microbial growth and proliferation.32,33 This interaction is particularly important for iron-loaded patients who are using chelating medicines and other similar drugs almost daily for their entire lives.22
Molecular insights into probiotic mechanisms of action employed against intestinal pathogenic bacteria
Published in Gut Microbes, 2020
Winschau F. van Zyl, Shelly M. Deane, Leon M.T. Dicks
Iron is an essential micronutrient that plays a central role in the metabolism and proliferation of most gut microbes, including commensal bacteria and gut pathogens.184 Siderophores are LMW, organic, high-affinity iron-chelating compounds produced by microorganisms such as bacteria and fungi.185 These compounds inhibit the growth, proliferation and persistence of competing microbes by depriving them of iron. In doing so, siderophore-producing bacteria sequester free iron available in their environment that is essential to other microorganisms. For example, the growth of Lc. lactis, C. difficile and Clostridium perfringens was inhibited in the GIT by iron-binding Bifidobacterium strains that produce siderophores.186 Growth and adhesion of enteropathogenic S. typhimurium N15 and EHEC to IECs were inhibited by B. pseudolongum PV8-2 and Bifidobacterium kashiwanohense PV20-2 with high iron sequestration properties.187
Drug discovery through the isolation of natural products from Burkholderia
Published in Expert Opinion on Drug Discovery, 2021
Adam Foxfire, Andrew Riley Buhrow, Ravi S. Orugunty, Leif Smith
Siderophores are a class of well-studied, low molecular weight chelators that have a high affinity for iron (in the biologically available form of Fe3+) and are produced by a broad array of microbes. Biomedical therapies have already been developed for their use in the treatment of iron-overload-related diseases, and there is some interest in utilizing them to create targeted antimicrobials by conjugation of siderophores to antimicrobials [18]. Many of the siderophores produced by Burkholderia are non-ribosomally synthesized peptides [19]. Of 25 members of Burkholderia to be examined for production of siderophores, 23 were confirmed to produce at least one of the compounds discussed herein [20]. Comprehensive studies on siderophores, including the siderophores in Burkholderia, can be found in the following papers [19,21–23].
Related Knowledge Centers
- Chelation
- Ferritin
- Iron
- Lactoferrin
- Active Transport
- Hemoglobin
- Homeostasis
- Coordination Complex
- NONribosomal Peptide
- Transferrin