biostudies-literatureFukushima TNIAID NIH HHSNational Institutes of Health2092-100https://www.ebi.ac.uk/biostudies/studies/S-EPMC4168784biostudies-literatureUnknown9(9)Iron is an essential element for all organisms, and microorganisms produce small molecule iron-chelators, siderophores, to efficiently acquire Fe(III). Gram-positive bacteria possess lipoprotein siderophore-binding proteins (SBPs) on the membrane. Some of the SBPs bind both apo-siderophores (iron-free) and Fe-siderophore (iron-chelated) and only import Fe-siderophores. When the SBP initially binds an apo-siderophore, the SBP uses the Gram-positive siderophore-shuttle mechanism (the SBPs exchange Fe(III) from a Fe-siderophore to the apo-siderophore bound to the protein) and/or displacement mechanism (the apo-siderophore bound to the SBP is released and a Fe-siderophore is then bound to the protein) to import the Fe-siderophore. Previously, we reported that the Bacillus cereus SBP, YxeB, excACS chemical biologyDirect evidence of iron uptake by the Gram-positive siderophore-shuttle mechanism without iron reduction.PMC4168784R01 AI011744AI11744Allred BERaymond KNFukushima TfalseDirect evidence of iron uptake by the Gram-positive siderophore-shuttle mechanism without iron reduction.Iron is an essential element for all organisms, and microorganisms produce small molecule iron-chelators, siderophores, to efficiently acquire Fe(III). Gram-positive bacteria possess lipoprotein siderophore-binding proteins (SBPs) on the membrane. Some of the SBPs bind both apo-siderophores (iron-free) and Fe-siderophore (iron-chelated) and only import Fe-siderophores. When the SBP initially binds an apo-siderophore, the SBP uses the Gram-positive siderophore-shuttle mechanism (the SBPs exchange Fe(III) from a Fe-siderophore to the apo-siderophore bound to the protein) and/or displacement mechanism (the apo-siderophore bound to the SBP is released and a Fe-siderophore is then bound to the protein) to import the Fe-siderophore. Previously, we reported that the Bacillus cereus SBP, YxeB, exc2014-01-01T00:00:00Z2014 Sep2025-04-22T21:08:52.041Z2019-03-27T01:35:56ZS-EPMC41687842500717410.1021/cb500319n