GNPS - Mass Spectrometry-Based Metabolomics for Siderophore Discovery
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Q Exactive HF
ORGANISM(S): Lab Standard
SUBMITTER: 
Allegra Aron
PROVIDER: MSV000094749 | GNPS | Mon May 13 12:44:00 BST 2024
REPOSITORIES: GNPS
Similar Datasets
Project description:Serratia marcescens is a bacterium frequently found in the environment, but over the last several decades it has evolved into a concerning clinical pathogen, causing fatal bacteremia. To establish such infections, pathogens require specific nutrients; one very limited but essential nutrient is iron. We sought to characterize the iron acquisition systems in S. marcescens isolate UMH9, which was recovered from a clinical bloodstream infection. Using RNA sequencing (RNA-seq), we identified two predicted siderophore gene clusters (cbs and sch) that were regulated by iron. Mutants were constructed to delete each iron acquisition locus individually and in conjunction, generating both single and double mutants for the putative siderophore systems. Mutants lacking the sch gene cluster lost their iron-chelating ability as quantified by the chrome azurol S (CAS) assay, whereas the cbs mutant retained wild-type activity. Mass spectrometry-based analysis identified the chelating siderophore to be serratiochelin, a siderophore previously identified in Serratia plymuthica. Serratiochelin-producing mutants also displayed a decreased growth rate under iron-limited conditions created by dipyridyl added to LB medium. Additionally, mutants lacking serratiochelin were significantly outcompeted during cochallenge with wild-type UMH9 in the kidneys and spleen after inoculation via the tail vein in a bacteremia mouse model. This result was further confirmed by an independent challenge, suggesting that serratiochelin is required for full S. marcescens pathogenesis in the bloodstream. Nine other clinical isolates have at least 90% protein identity to the UMH9 serratiochelin system; therefore, our results are broadly applicable to emerging clinical isolates of S. marcescens causing bacteremia.
2020-05-24 | GSE145587 | GEO
Project description:Competition for limited iron resources is a key driver of microbial community structure in many regions of the surface ocean. The bacterial siderophores ferrioxamine and amphibactin have been identified in marine surface waters, suggesting that they may represent an important bacterial strategy for obtaining iron from a scarcely populated pool. We screened several strains of marine Vibrio for the presence of putative amphibactin biosynthesis gene homologues and amphibactin production. Whole cell proteomics, siderophore isolation, and isotopically labeled iron uptake experiments were performed. Here, we show that an amphibactin-producing marine bacterium, Vibrio cyclitrophicus str. 1F-53, harbors an independently regulated uptake pathway for ferrioxamines. Proteomic analyses identified upregulation of the amphibactin NRPS system and a putative amphibactin siderophore transporter in response to low iron concentrations. In addition, multiple other transporters were upregulated, however when desferrioxamine was present, amphibactin production decreased and the ferrioxamine receptor increased in abundance. Such cheating phenotypes, which appear widespread among marine amphibactin producers, highlight the strategies that contribute to the fitness of marine bacteria in the face of iron stress. These results demonstrate siderophore producer and cheater phenotypes and highlight the cellular restructuring which is involved due to competition for iron, that shapes the community structure of marine ecosystems.
2021-04-19 | PXD011427 | Pride
Project description:Iron is an essential nutrient for bacterial growth but poorly bioavailable. To scavenge ferric iron present in their environment, bacteria synthesize and secrete siderophores, small compounds with a high affinity for iron. Pyochelin (PCH) is one of the two siderophores produced by the opportunistic pathogen Pseudomonas aeruginosa. Once having captured a ferric iron, PCH-Fe is imported back into bacteria first by the outer membrane transporter FptA and afterwards by the inner membrane permease FptX. Here using molecular biology, 55Fe uptake assays and LC-MS/MS quantification of PCH in the different bacterial cell fractions, we show that (i) PCH (probably under its PCH-Fe form) is able to rich bacterial periplasm and cytoplasm when both FptA and FptX are expressed, and (ii) that PchHI (a heterodimeric ABC transporter) plays a role in the translocation of siderophore-free iron siderophore-free iron across the inner membrane into the cytoplasm. Consequently, probably the first fraction of PCH-Fe internalized by FptA may be transported further by FptX in the bacterial cytoplasm to activate the transcriptional regulator PchR, regulating the transcription of all genes of the PCH pathway. The further fractions of PCH-Fe transported by FptA may dissociate in the bacterial periplasm by an unknown mechanism, with the siderophore-free iron being transported into the cytoplasm by PchHI.
2022-03-15 | PXD026833 | Pride
Project description:Exploiting the symbiotic interaction between crops and nitrogen-fixing bacteria is a simple and ecological solution to promote plants growth in prospective extraterrestrial human outposts. In this study, we investigated the adaptation of the legume symbiont Paraburkholderia phymatum to simulated microgravity (s0-g) at the transcriptome level by performing an RNA-Seq analysis. The results revealed a drastic effect on gene expression, with roughly 23 % of P. phymatum genes being differentially regulated in s0-g. Among those, 951 genes were upregulated and 858 downregulated in the cells grown in s0-g compared to terrestrial gravity (1g). Genes involved in posttranslational modification, proteins turnover and chaperones production were upregulated in s0-g, while those involved in translation, ribosomal structure and biosynthesis, motility or inorganic ions transport were downregulated. Specifically, the whole phm gene cluster, previously predicted to be involved in the production of a hypothetical siderophore, phymabactin, was approximatively 20-fold downregulated in microgravity. Accordingly, a phm-gfp reporter strain showed less expression in s0-g and iron uptake was reduced in microgravity. By constructing a mutant strain (ΔphmJK) we confirmed that the phm gene cluster codes for the only siderophore secreted by P. phymatum. In fact, in contrast to P. phymatum wild-type, ΔphmJK did not produce any siderophores on chrome azurol S plates. These results not only provide a deeper understanding of the physiology of symbiotic organisms exposed to space-like conditions, but also increase our understanding of iron acquisition in rhizobia.
2024-04-10 | GSE255155 | GEO
Project description:Pseudomonas and other environmental microorganisms have been proven capable of synthesizing siderophores, which are instrumental in the removal of iron and other metal ions from a variety of waste materials. We have elucidated the molecular mechanisms by which the BfmRS two-component system (TCS) mediates environmental stress signals to regulate siderophore production in Pseudomonas aeruginosa. In this study, we further confirm the pivotal role of the BfmRS system in bacterial iron metabolism, demonstrating its regulatory influence on key genes involved in siderophore synthesis. Moreover, overexpression of BfmR led to a marked increase in mRNA levels of siderophore-related genes, with a 2.4- to 6.7-fold elevation, which in turn significantly enhanced siderophore production and consequently improved iron utilization efficiency when compared to the wild type (WT). The heightened efficiency of the genetically modified strain to extract iron from coal fly ash (CFA) suggests the feasibility of engineered bacterial system in bioremediation. This work not only validate the intricate TCSs involved in siderophore regulation within P. aeruginosa, but also provides a compelling strategy in heavy metal recovery and hazardous waste detoxification.
2023-12-25 | PXD048123 | iProX
Project description:We investigated the function of the SNX/H-type regulator of G-protein signaling (RGS) protein RGS4 and found alterations in enzyme regulation, stress response, siderophore production and metabolism of several carbon sources in light and darkness
2022-12-12 | GSE216955 | GEO
Project description:LC-HRMS/MS data for chemical profiling of in vitro micropropagated Melia azedarach. Dataset includes raw and converted LC-HRMS/MS files, feature finding output and batch file with processing modules and parameters, dataset metadata and SIRIUS output.
| MSV000092881 | MassIVE
Project description:Iron is an essential nutrient for the opportunistic pathogen Pseudomonas aeruginosa, as for almost all living organisms. To access this element, the pathogen is able to express at least 15 different iron-uptake pathways, the vast majority involving small iron chelators called siderophores. Indeed, P. aeruginosa produces two siderophores, pyoverdine and pyochelin, but can also use many produced by other microorganisms. This implies that the bacterium expresses appropriate TonB-dependent transporters (TBDTs) at the outer membrane to import the ferric form of each of the siderophores used. These transporters are highly selective for a given ferri-siderophore complex or for siderophores with similar chemical structures. Here, we show that P. aeruginosa can also use rhizoferrin, staphyloferrin A, aerobactin, and schizokinen as siderophores to access iron. Growth assays in iron-restricted conditions and 55Fe uptake assays showed that the two alpha-carboxylate type siderophores rhizoferrin-Fe and staphyloferrin A-Fe are transported into P. aeruginosa cells by the TBDT ActA (PA3268). Among the mixed alpha-carboxylate/hydroxamate type siderophores, we found aerobactin-Fe to be transported by ChtA (as previously described) and schizokinen-Fe by ChtA and another unidentified TBDT.
2023-09-21 | PXD043056 | Pride
Project description:The aim of the experiment was to identify genes differentially expressed between the susceptible wild type strain P. aeruginosa PAO1 (PT5) and a mutant resistant to a drug-siderophore conjugate, in order to obtain information on the resistance mechanism(s). A mutant of PT5 able to grow at 4 mg/l BAL30072, a drug-siderophore conjugate, was selected in vitro . The susceptible wild type strain PT5 and the mutant (BAL6) were grown in LB medium and the mutant also in the presence of 4 mg/l BAL30072 to mid-exponential growth phase (OD600 =2) in triplicate cultures. RNA was extracted using the RNeasy Kit (Qiagen). A total of nine Affymterix P. aeruginosa arrays were hybridized (one for each replicate) under standard conditions.
2013-04-17 | E-MTAB-1381 | biostudies-arrayexpress
Project description:Iron was titrated into 5 commercial siderophore standards to calculate dissociation constants.
2020-03-14 | MSV000085102 | GNPS