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Sun Q, Yu D, Zhang X, Xiao F, Li W. The Discovery of Cyclic Lipopeptide Olenamidonins in a Deepsea-Derived Streptomyces Strain by Knocking Out a DtxR Family Regulator. Mar Drugs 2024; 22:262. [PMID: 38921573 PMCID: PMC11204786 DOI: 10.3390/md22060262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 06/03/2024] [Accepted: 06/03/2024] [Indexed: 06/27/2024] Open
Abstract
Three new cyclic lipopeptides, olenamidonins A-C (1-3), in addition to two previously reported metabolites (4 and 5), were accumulated in the ΔdtxRso deletion mutant of deepsea-derived Streptomyces olivaceus SCSIO 1071. The structures of these cyclic lipopeptides were determined by a combination of spectroscopic methods and circular dichroism (CD) measurement. The antibacterial assay results showed that compounds 1-5 displayed different degrees of growth inhibition against multidrug-resistant (MDR) bacterial strains Enterococcus faecalis CCARM 5172 and Enterococcus faecium CCARM 5203 with minimum inhibitory concentrations (MICs) of 1.56-6.25 μg/mL.
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Affiliation(s)
- Qiannan Sun
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266071, China; (Q.S.); (D.Y.); (X.Z.)
| | - Dongqi Yu
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266071, China; (Q.S.); (D.Y.); (X.Z.)
| | - Xueqing Zhang
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266071, China; (Q.S.); (D.Y.); (X.Z.)
| | - Fei Xiao
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266071, China; (Q.S.); (D.Y.); (X.Z.)
| | - Wenli Li
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266071, China; (Q.S.); (D.Y.); (X.Z.)
- Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266000, China
- College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, China
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2
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Wang S, Fang R, Wang H, Li X, Xing J, Li Z, Song N. The role of transcriptional regulators in metal ion homeostasis of Mycobacterium tuberculosis. Front Cell Infect Microbiol 2024; 14:1360880. [PMID: 38529472 PMCID: PMC10961391 DOI: 10.3389/fcimb.2024.1360880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Accepted: 02/27/2024] [Indexed: 03/27/2024] Open
Abstract
Metal ions are essential trace elements for all living organisms and play critical catalytic, structural, and allosteric roles in many enzymes and transcription factors. Mycobacterium tuberculosis (MTB), as an intracellular pathogen, is usually found in host macrophages, where the bacterium can survive and replicate. One of the reasons why Tuberculosis (TB) is so difficult to eradicate is the continuous adaptation of its pathogen. It is capable of adapting to a wide range of harsh environmental stresses, including metal ion toxicity in the host macrophages. Altering the concentration of metal ions is the common host strategy to limit MTB replication and persistence. This review mainly focuses on transcriptional regulatory proteins in MTB that are involved in the regulation of metal ions such as iron, copper and zinc. The aim is to offer novel insights and strategies for screening targets for TB treatment, as well as for the development and design of new therapeutic interventions.
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Affiliation(s)
- Shuxian Wang
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
| | - Ren Fang
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
| | - Hui Wang
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
| | - Xiaotian Li
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
| | - Jiayin Xing
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
| | - Zhaoli Li
- Drug Innovation Research Center, SAFE Pharmaceutical Technology Co. Ltd., Beijing, China
| | - Ningning Song
- Key Laboratory of Respiratory Tract Pathogens and Drug Therapy, School of Life Science and Technology, Shandong Second Medical University, Weifang, China
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Marcos-Torres FJ, Juniar L, Griese JJ. The molecular mechanisms of the bacterial iron sensor IdeR. Biochem Soc Trans 2023:233013. [PMID: 37140254 DOI: 10.1042/bst20221539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/12/2023] [Accepted: 04/18/2023] [Indexed: 05/05/2023]
Abstract
Life came to depend on iron as a cofactor for many essential enzymatic reactions. However, once the atmosphere was oxygenated, iron became both scarce and toxic. Therefore, complex mechanisms have evolved to scavenge iron from an environment in which it is poorly bioavailable, and to tightly regulate intracellular iron contents. In bacteria, this is typically accomplished with the help of one key regulator, an iron-sensing transcription factor. While Gram-negative bacteria and Gram-positive species with low guanine-cytosine (GC) content generally use Fur (ferric uptake regulator) proteins to regulate iron homeostasis, Gram-positive species with high GC content use the functional homolog IdeR (iron-dependent regulator). IdeR controls the expression of iron acquisition and storage genes, repressing the former, and activating the latter in an iron-dependent manner. In bacterial pathogens such as Corynebacterium diphtheriae and Mycobacterium tuberculosis, IdeR is also involved in virulence, whereas in non-pathogenic species such as Streptomyces, it regulates secondary metabolism as well. Although in recent years the focus of research on IdeR has shifted towards drug development, there is much left to learn about the molecular mechanisms of IdeR. Here, we summarize our current understanding of how this important bacterial transcriptional regulator represses and activates transcription, how it is allosterically activated by iron binding, and how it recognizes its DNA target sites, highlighting the open questions that remain to be addressed.
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Affiliation(s)
- Francisco Javier Marcos-Torres
- Department of Cell and Molecular Biology, Uppsala University, 751 24 Uppsala, Sweden
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín-CSIC, 18011 Granada, Spain
| | - Linda Juniar
- Department of Cell and Molecular Biology, Uppsala University, 751 24 Uppsala, Sweden
| | - Julia J Griese
- Department of Cell and Molecular Biology, Uppsala University, 751 24 Uppsala, Sweden
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4
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Enuh BM, Aytar Çelik P. Insight into the biotechnology potential of Alicyclobacillus tolerans from whole genome sequence analysis and genome-scale metabolic network modeling. J Microbiol Methods 2022; 197:106459. [PMID: 35395336 DOI: 10.1016/j.mimet.2022.106459] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 03/31/2022] [Accepted: 03/31/2022] [Indexed: 12/27/2022]
Abstract
Extremophilic bacteria have numerous uncovered biotechnological potentials. Acidophilic bacteria are important iron oxidizers that are valuable in bioleaching and in studying extreme environments on earth and in space. Despite their obvious potential, little is known about the genetic traits that underpin their metabolic functions, which are equally poorly understood from a mechanistic perspective. Novel bioinformatics and computational biology pipelines can be used to analyze whole genomes to obtain insights into the phenotypic potential of organisms as well as develop a mathematical model representation of metabolism. Whole-genome sequence analysis and a genome-scale metabolic network model was curated for an iron-oxidizing bacterium initially isolated from an acid mine drainage in Turkey, previously identified as Alicyclobacillus tolerans. The genome contained a high proportion of genes for energy generation from carbohydrates, amino acids synthesis and conversion, nucleic acid metabolism and repair which contribute to robust adaption to their extreme environments. Several candidate genes for pyrite metabolism, iron uptake, regulation and storage, as well as genes for resistance to important heavy metals were annotated. A curated genome-scale metabolic network analysis accurately predicted facultative anaerobic growth, heterotrophic characteristics, and growth on a wide variety of carbon sources. This is the first in-depth in silico analysis of A. tolerans to the best of our knowledge which is expected to lay the groundwork for future research and drive innovations in environmental microbiology and biotechnological applications. The genomic data and mechanistic framework will have applications in biomining, synthetic geomicrobiology on earth, as well as for space exploration and settlement.
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Affiliation(s)
- Blaise Manga Enuh
- Department of Biotechnology and Biosafety, Graduate School of Natural and Applied Science, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey
| | - Pınar Aytar Çelik
- Department of Biotechnology and Biosafety, Graduate School of Natural and Applied Science, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey; Environmental Protection and Control Program, Eskişehir Osmangazi University, Eskişehir 26110, Turkey.
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5
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Marcos-Torres FJ, Maurer D, Juniar L, Griese JJ. The bacterial iron sensor IdeR recognizes its DNA targets by indirect readout. Nucleic Acids Res 2021; 49:10120-10135. [PMID: 34417623 PMCID: PMC8464063 DOI: 10.1093/nar/gkab711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/19/2021] [Accepted: 08/02/2021] [Indexed: 01/11/2023] Open
Abstract
The iron-dependent regulator IdeR is the main transcriptional regulator controlling iron homeostasis genes in Actinobacteria, including species from the Corynebacterium, Mycobacterium and Streptomyces genera, as well as the erythromycin-producing bacterium Saccharopolyspora erythraea. Despite being a well-studied transcription factor since the identification of the Diphtheria toxin repressor DtxR three decades ago, the details of how IdeR proteins recognize their highly conserved 19-bp DNA target remain to be elucidated. IdeR makes few direct contacts with DNA bases in its target sequence, and we show here that these contacts are not required for target recognition. The results of our structural and mutational studies support a model wherein IdeR mainly uses an indirect readout mechanism, identifying its targets via the sequence-dependent DNA backbone structure rather than through specific contacts with the DNA bases. Furthermore, we show that IdeR efficiently recognizes a shorter palindromic sequence corresponding to a half binding site as compared to the full 19-bp target previously reported, expanding the number of potential target genes controlled by IdeR proteins.
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Affiliation(s)
| | - Dirk Maurer
- Department of Cell and Molecular Biology, Uppsala University, SE-751 24 Uppsala, Sweden
| | - Linda Juniar
- Department of Cell and Molecular Biology, Uppsala University, SE-751 24 Uppsala, Sweden
| | - Julia J Griese
- Department of Cell and Molecular Biology, Uppsala University, SE-751 24 Uppsala, Sweden
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Ghio AJ, Soukup JM, Dailey LA, Madden MC. Air pollutants disrupt iron homeostasis to impact oxidant generation, biological effects, and tissue injury. Free Radic Biol Med 2020; 151:38-55. [PMID: 32092410 PMCID: PMC8274387 DOI: 10.1016/j.freeradbiomed.2020.02.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 01/27/2020] [Accepted: 02/10/2020] [Indexed: 02/07/2023]
Abstract
Air pollutants cause changes in iron homeostasis through: 1) a capacity of the pollutant, or a metabolite(s), to complex/chelate iron from pivotal sites in the cell or 2) an ability of the pollutant to displace iron from pivotal sites in the cell. Through either pathway of disruption in iron homeostasis, metal previously employed in essential cell processes is sequestered after air pollutant exposure. An absolute or functional cell iron deficiency results. If enough iron is lost or is otherwise not available within the cell, cell death ensues. However, prior to death, exposed cells will attempt to reverse the loss of requisite metal. This response of the cell includes increased expression of metal importers (e.g. divalent metal transporter 1). Oxidant generation after exposure to air pollutants includes superoxide production which functions in ferrireduction necessary for cell iron import. Activation of kinases and phosphatases and transcription factors and increased release of pro-inflammatory mediators also result from a cell iron deficiency, absolute or functional, after exposure to air pollutants. Finally, air pollutant exposure culminates in the development of inflammation and fibrosis which is a tissue response to the iron deficiency challenging cell survival. Following the response of increased expression of importers and ferrireduction, activation of kinases and phosphatases and transcription factors, release of pro-inflammatory mediators, and inflammation and fibrosis, cell iron is altered, and a new metal homeostasis is established. This new metal homeostasis includes increased total iron concentrations in cells with metal now at levels sufficient to meet requirements for continued function.
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Affiliation(s)
- Andrew J Ghio
- From the National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Chapel Hill, NC, USA.
| | - Joleen M Soukup
- From the National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Chapel Hill, NC, USA
| | - Lisa A Dailey
- From the National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Chapel Hill, NC, USA
| | - Michael C Madden
- From the National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Chapel Hill, NC, USA
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7
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Barral TD, Mariutti RB, Arni RK, Santos AJ, Loureiro D, Sokolonski AR, Azevedo V, Borsuk S, Meyer R, Portela RD. A panel of recombinant proteins for the serodiagnosis of caseous lymphadenitis in goats and sheep. Microb Biotechnol 2019; 12:1313-1323. [PMID: 31287241 PMCID: PMC6801148 DOI: 10.1111/1751-7915.13454] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 05/29/2019] [Accepted: 06/03/2019] [Indexed: 12/11/2022] Open
Abstract
Caseous lymphadenitis (CLA) is a small ruminant disease characterized by the development of granulomatous lesions in superficial and internal lymph nodes, as well as in some organs, and causes significant economic losses worldwide. The aetiological agent of CLA is the bacterium Corynebacterium pseudotuberculosis; however, the commercially available diagnostic tools present problems with regard to specificity, which can lead to false-negative results. This study aimed to develop an indirect enzyme-linked immunosorbent assay (ELISA) for the detection of specific immunoglobulins in goats and sheep using recombinant C. pseudotuberculosis PLD, CP40, PknG, DtxR and Grx proteins. For validation of the ELISAs, 130 goat serum samples and 160 sheep serum samples were used. The best ELISA for goats was developed using a combination of PLD and CP40 as antigens at a 1:1 ratio, which presented 96.9% sensitivity and 98.4% specificity. The most effective ELISA for sheep presented 91% sensitivity and 98.7% specificity when recombinant PLD alone was used as the antigen. These ELISAs can be used as highly accurate tools in epidemiological surveys and for the serodiagnosis of C. pseudotuberculosis infection in goats and sheep.
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Affiliation(s)
- Thiago Doria Barral
- Laboratório de Imunologia e Biologia MolecularICS‐UFBASalvadorBA40110‐100Brasil
| | | | | | | | - Dan Loureiro
- Laboratório de Imunologia e Biologia MolecularICS‐UFBASalvadorBA40110‐100Brasil
| | - Ana Rita Sokolonski
- Laboratório de Imunologia e Biologia MolecularICS‐UFBASalvadorBA40110‐100Brasil
| | - Vasco Azevedo
- Laboratório de Genética Celular e MolecularICB‐UFMGBelo HorizonteMG31270‐901Brasil
| | - Sibele Borsuk
- Laboratório de Biotecnologia Infecto‐parasitáriaCDT‐UFPelPelotasRS96010‐900Brasil
| | - Roberto Meyer
- Laboratório de Imunologia e Biologia MolecularICS‐UFBASalvadorBA40110‐100Brasil
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Cooper B, Islam N, Xu Y, Beard HS, Garrett WM, Gu G, Nou X. Quantitative Proteomic Analysis of
Staphylococcus aureus
Treated With Punicalagin, a Natural Antibiotic From Pomegranate That Disrupts Iron Homeostasis and Induces SOS. Proteomics 2018. [DOI: 10.1002/pmic.201700461] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Bret Cooper
- Soybean Genomics and Improvement Laboratory USDA‐ARS Beltsville MD USA
| | - Nazrul Islam
- Department of Food Science and Human Nutrition University of Maryland College Park MD USA
| | - Yunfeng Xu
- College of Food Science and Engineering Northwest A&F University Yangling P. R. China
| | - Hunter S. Beard
- Soybean Genomics and Improvement Laboratory USDA‐ARS Beltsville MD USA
| | - Wesley M. Garrett
- Animal Biosciences and Biotechnology Laboratory USDA‐ARS Beltsville MD USA
| | - Ganyu Gu
- Virginia Tech Eastern Shore Agricultural Research and Extension Centers Painter VA USA
| | - Xiangwu Nou
- Environmental Microbial and Food Safety Laboratory USDA‐ARS Beltsville MD USA
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Yin YR, Meng ZH, Hu QW, Jiang Z, Xian WD, Li LH, Hu W, Zhang F, Zhou EM, Zhi XY, Li WJ. The Hybrid Strategy of Thermoactinospora rubra YIM 77501 T for Utilizing Cellulose as a Carbon Source at Different Temperatures. Front Microbiol 2017; 8:942. [PMID: 28611745 PMCID: PMC5447088 DOI: 10.3389/fmicb.2017.00942] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 05/10/2017] [Indexed: 01/02/2023] Open
Abstract
Thermoactinospora rubra YIM 77501T is an aerobic, Gram-positive, spore-forming and cellulose degrading thermophilic actinomycete isolated from a sandy soil sample of a volcano. Its growth temperature range is 28–60°C. The genomic sequence of this strain revealed that there are 27 cellulase genes belonging to six glycoside hydrolase families. To understand the strategy that this strain uses to utilize carbon sources such as cellulose at different temperatures, comparative transcriptomics analysis of T. rubra YIM 77501T was performed by growing it with cellulose (CMC) and without cellulose (replaced with glucose) at 30, 40, and 50°C, respectively. Transcriptomic analyses showed four cellulase genes (TrBG2, TrBG3, TrBG4, and ThrCel6B) were up-regulated at 30, 40, and 50°C. The rate of gene expression of TrBG2, TrBG3, TrBG4, and ThrCel6B were 50°C > 30°C > 40°C. One cellulase gene (TrBG1) and two cellulase genes (TrBG5 and ThrCel6A) were up-regulated only at 30 and 50°C, respectively. These up-regulated cellulase genes were cloned and expressed in Escherichia coli. The enzymatic properties of up-regulated cellulases showed a variety of responses to temperature. Special up-regulated cellulases TrBG1 and ThrCel6A displayed temperature acclimation for each growth condition. These expression patterns revealed that a hybrid strategy was used by T. rubra to utilize carbon sources at different temperatures. This study provides genomic, transcriptomics, and experimental data useful for understanding how microorganisms respond to environmental changes and their application in enhancing cellulose hydrolysis for animal feed and bioenergy production.
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Affiliation(s)
- Yi-Rui Yin
- School of Life Sciences, Yunnan Institute of Microbiology, Yunnan UniversityKunming, China
| | - Zhao-Hui Meng
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical UniversityKunming, China
| | - Qing-Wen Hu
- School of Life Sciences, Yunnan Institute of Microbiology, Yunnan UniversityKunming, China
| | - Zhao Jiang
- School of Life Sciences, Yunnan Institute of Microbiology, Yunnan UniversityKunming, China
| | - Wen-Dong Xian
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-Sen UniversityGuangzhou, China
| | - Lin-Hua Li
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical UniversityKunming, China
| | - Wei Hu
- Department of Cardiology, The First Affiliated Hospital of Kunming Medical UniversityKunming, China
| | - Feng Zhang
- Key Laboratory of Biopesticide and Chemical Biology, School of Life Sciences, Fujian Agriculture and Forestry UniversityFuzhou, China
| | - En-Min Zhou
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-Sen UniversityGuangzhou, China
| | - Xiao-Yang Zhi
- School of Life Sciences, Yunnan Institute of Microbiology, Yunnan UniversityKunming, China
| | - Wen-Jun Li
- School of Life Sciences, Yunnan Institute of Microbiology, Yunnan UniversityKunming, China.,State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-Sen UniversityGuangzhou, China.,Key Laboratory of Biogeography and Bioresource in Arid Land, Xinjiang Institute of Ecology and Geography, Chinese Academy of SciencesÜrümqi, China
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Li K, Chen WH, Bruner SD. Structure and Mechanism of the Siderophore-Interacting Protein from the Fuscachelin Gene Cluster of Thermobifida fusca. Biochemistry 2015; 54:3989-4000. [PMID: 26043104 DOI: 10.1021/acs.biochem.5b00354] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Microbial iron acquisition is a complex process and frequently a key and necessary step for survival. Among the several paths for iron assimilation, small molecule siderophore-mediated transport is a commonly employed strategy of many microorganisms. The chemistry and biology of the extraordinary tight and specific binding of siderophores to metal is also exploited in therapeutic treatments for microbial virulence and metal toxicity. The intracellular fate of iron acquired via the siderophore pathway is one of the least understood steps in the complex process at the molecular level. A common route to cellular incorporation is the single-electron reduction of ferric to ferrous iron catalyzed by specific and/or nonspecific reducing agents. The biosynthetic gene clusters for siderophores often contain representatives of one or two families of redox-active enzymes: the flavin-containing "siderophore-interacting protein" and iron-sulfur ferric siderophore reductases. Here we present the structure and characterization of the siderophore-interacting protein, FscN, from the fuscachelin siderophore gene cluster of Thermobifida fusca. The structure shows a flavoreductase fold with a noncovalently bound FAD cofactor along with an unexpected metal bound adjacent to the flavin site. We demonstrated that FscN is redox-active and measured the binding and reduction of ferric fuscachelin. This work provides a structural basis for the activity of a siderophore-interacting protein and further insight into the complex and important process of iron acquisition and utilization.
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Affiliation(s)
- Kunhua Li
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Wei-Hung Chen
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Steven D Bruner
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
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