Article ; Online: Gram-positive siderophore-shuttle with iron-exchange from Fe-siderophore to apo-siderophore by Bacillus cereus YxeB.
Proceedings of the National Academy of Sciences of the United States of America
2013 Volume 110, Issue 34, Page(s) 13821–13826
Abstract: Small molecule iron-chelators, siderophores, are very important in facilitating the acquisition of Fe(III), an essential element for pathogenic bacteria. Many Gram-negative outer-membrane transporters and Gram-positive lipoprotein siderophore-binding ... ...
Abstract | Small molecule iron-chelators, siderophores, are very important in facilitating the acquisition of Fe(III), an essential element for pathogenic bacteria. Many Gram-negative outer-membrane transporters and Gram-positive lipoprotein siderophore-binding proteins have been characterized, and the binding ability of outer-membrane transporters and siderophore-binding proteins for Fe-siderophores has been determined. However, there is little information regarding the binding ability of these proteins for apo-siderophores, the iron-free chelators. Here we report that Bacillus cereus YxeB facilitates iron-exchange from Fe-siderophore to apo-siderophore bound to the protein, the first Gram-positive siderophore-shuttle system. YxeB binds ferrioxamine B (FO, Fe-siderophore)/desferrioxamine B (DFO, apo-siderophore) in vitro. Disc-diffusion assays and growth assays using the yxeB mutant reveal that YxeB is responsible for importing the FO. Cr-DFO (a FO analog) is bound by YxeB in vitro and B. cereus imports or binds Cr-DFO in vivo. In vivo uptake assays using Cr-DFO and FO and growth assays using DFO and Cr-DFO show that B. cereus selectively imports and uses FO when DFO is present. Moreover, in vitro competition assays using Cr-DFO and FO clearly demonstrate that YxeB binds only FO, not Cr-DFO, when DFO is bound to the protein. Iron-exchange from FO to DFO bound to YxeB must occur when DFO is initially bound by YxeB. Because the metal exchange rate is generally first order in replacement ligand concentration, protein binding of the apo-siderophore acts to dramatically enhance the iron exchange rate, a key component of the Gram-positive siderophore-shuttle mechanism. |
---|---|
MeSH term(s) | Bacillus cereus/metabolism ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Binding, Competitive ; Biological Transport/physiology ; Chromatography, High Pressure Liquid ; Deferoxamine/metabolism ; Disk Diffusion Antimicrobial Tests ; Ferric Compounds/metabolism ; Fluorescence ; Mass Spectrometry ; Plasmids/genetics ; Protein Binding ; Regression Analysis ; Siderophores/metabolism |
Chemical Substances | Bacterial Proteins ; Ferric Compounds ; Siderophores ; ferrioxamine B (4A0UG9NR9K) ; Deferoxamine (J06Y7MXW4D) |
Language | English |
Publishing date | 2013-08-07 |
Publishing country | United States |
Document type | Journal Article ; Research Support, N.I.H., Extramural |
ZDB-ID | 209104-5 |
ISSN | 1091-6490 ; 0027-8424 |
ISSN (online) | 1091-6490 |
ISSN | 0027-8424 |
DOI | 10.1073/pnas.1304235110 |
Database | MEDical Literature Analysis and Retrieval System OnLINE |
More links
Kategorien
In stock of ZB MED Cologne/Königswinter
Zs.A 1148: Show issues | Location: Je nach Verfügbarkeit (siehe Angabe bei Bestand) bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular Jg. 1995 - 2021: Lesesall (1.OG) ab Jg. 2022: Lesesaal (EG) |
Order via subito
This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.