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Sun Y, Liu M, Sun W, Tang X, Zhou Y, Zhang J, Yang B. A Hemoglobin Bionics-Based System for Combating Antibiotic Resistance in Chronic Diabetic Wounds via Iron Homeostasis Regulation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2405002. [PMID: 38738270 DOI: 10.1002/adma.202405002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Revised: 05/09/2024] [Indexed: 05/14/2024]
Abstract
Owing to the increased tissue iron accumulation in patients with diabetes, microorganisms may activate high expression of iron-involved metabolic pathways, leading to the exacerbation of bacterial infections and disruption of systemic glucose metabolism. Therefore, an on-demand transdermal dosing approach that utilizes iron homeostasis regulation to combat antimicrobial resistance is a promising strategy to address the challenges associated with low administration bioavailability and high antibiotic resistance in treating infected diabetic wounds. Here, it is aimed to propose an effective therapy based on hemoglobin bionics to induce disturbances in bacterial iron homeostasis. The preferred "iron cargo" is synthesized by protoporphyrin IX chelated with dopamine and gallium (PDGa), and is delivered via a glucose/pH-responsive microneedle bandage (PDGa@GMB). The PDGa@GMB downregulates the expression levels of the iron uptake regulator (Fur) and the peroxide response regulator (perR) in Staphylococcus aureus, leading to iron nutrient starvation and oxidative stress, ultimately suppressing iron-dependent bacterial activities. Consequently, PDGa@GMB demonstrates insusceptibility to genetic resistance while maintaining sustainable antimicrobial effects (>90%) against resistant strains of both S. aureus and E. coli, and accelerates tissue recovery (<20 d). Overall, PDGa@GMB not only counteracts antibiotic resistance but also holds tremendous potential in mediating microbial-host crosstalk, synergistically attenuating pathogen virulence and pathogenicity.
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Affiliation(s)
- Yihan Sun
- Joint Laboratory of Opto, Functional Theranostics in Medicine and Chemistry, The First Hospital of Jilin University, Changchun, 130021, P. R. China
- State Key Laboratory of Supramolecular Structure and Material, Center for Supramolecular Chemical Biology, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Manxuan Liu
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Hospital of Stomatology, Jilin University, Changchun, 130021, P. R. China
| | - Weihong Sun
- Joint Laboratory of Opto, Functional Theranostics in Medicine and Chemistry, The First Hospital of Jilin University, Changchun, 130021, P. R. China
- State Key Laboratory of Supramolecular Structure and Material, Center for Supramolecular Chemical Biology, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Xiaoduo Tang
- Joint Laboratory of Opto, Functional Theranostics in Medicine and Chemistry, The First Hospital of Jilin University, Changchun, 130021, P. R. China
- State Key Laboratory of Supramolecular Structure and Material, Center for Supramolecular Chemical Biology, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Hospital of Stomatology, Jilin University, Changchun, 130021, P. R. China
| | - Yanmin Zhou
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Hospital of Stomatology, Jilin University, Changchun, 130021, P. R. China
| | - Junhu Zhang
- Joint Laboratory of Opto, Functional Theranostics in Medicine and Chemistry, The First Hospital of Jilin University, Changchun, 130021, P. R. China
- State Key Laboratory of Supramolecular Structure and Material, Center for Supramolecular Chemical Biology, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Bai Yang
- Joint Laboratory of Opto, Functional Theranostics in Medicine and Chemistry, The First Hospital of Jilin University, Changchun, 130021, P. R. China
- State Key Laboratory of Supramolecular Structure and Material, Center for Supramolecular Chemical Biology, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
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2
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Liu F, Kou Q, Li H, Cao Y, Chen M, Meng X, Zhang Y, Wang T, Wang H, Zhang D, Yang Y. Discovery of YFJ-36: Design, Synthesis, and Antibacterial Activities of Catechol-Conjugated β-Lactams against Gram-Negative Bacteria. J Med Chem 2024; 67:6705-6725. [PMID: 38596897 DOI: 10.1021/acs.jmedchem.4c00265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Cefiderocol is the first approved catechol-conjugated cephalosporin against multidrug-resistant Gram-negative bacteria, while its application was limited by poor chemical stability associated with the pyrrolidinium linker, moderate potency against Klebsiella pneumoniae and Acinetobacter baumannii, intricate procedures for salt preparation, and potential hypersensitivity. To address these issues, a series of novel catechol-conjugated derivatives were designed, synthesized, and evaluated. Extensive structure-activity relationships and structure-metabolism relationships (SMR) were conducted, leading to the discovery of a promising compound 86b (Code no. YFJ-36) with a new thioether linker. 86b exhibited superior and broad-spectrum in vitro antibacterial activity, especially against A. baumannii and K. pneumoniae, compared with cefiderocol. Potent in vivo efficacy was observed in a murine systemic infection model. Furthermore, the physicochemical stability of 86b in fluid medium at pH 6-8 was enhanced. 86b also reduced potential the risk of allergy owing to the quaternary ammonium linker. The improved properties of 86b supported its further research and development.
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Affiliation(s)
- Fangjun Liu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China
| | - Qunhuan Kou
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China
| | - Hongyuan Li
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China
| | - Yangzhi Cao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China
| | - Meng Chen
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China
| | - Xin Meng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Yinyong Zhang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China
| | - Ting Wang
- Department of Microbiology, Sichuan Primed Bio-Tech Group Co., Ltd., Chengdu, Sichuan Province 610041, P. R. China
| | - Hui Wang
- China Pharmaceutical University, Jiangsu 211198, China
| | - Dan Zhang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Yushe Yang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China
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3
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Will V, Gasser V, Kuhn L, Fritsch S, Heinrichs DE, Schalk IJ. Siderophore specificities of the Pseudomonas aeruginosa TonB-dependent transporters ChtA and ActA. FEBS Lett 2023; 597:2963-2974. [PMID: 37758521 DOI: 10.1002/1873-3468.14740] [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: 07/27/2023] [Revised: 09/12/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023]
Abstract
Iron is an essential nutrient for the survival and virulence of Pseudomonas aeruginosa. The pathogen expresses at least 15 different iron-uptake pathways, the majority involving small iron chelators called siderophores. P. aeruginosa produces two siderophores, 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. Here, we show that the two α-carboxylate-type siderophores rhizoferrin-Fe and staphyloferrin A-Fe are transported into P. aeruginosa cells by the TBDT ActA. Among the mixed α-carboxylate/hydroxamate-type siderophores, we found aerobactin-Fe to be transported by ChtA and schizokinen-Fe and arthrobactin-Fe by ChtA and another unidentified TBDT. Our findings enhance the understanding of the adaptability of P. aeruginosa and hold significant implications for developing novel strategies to combat antibiotic resistance.
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Affiliation(s)
- Virginie Will
- CNRS, University of Strasbourg, UMR7242, ESBS, Strasbourg, France
- University of Strasbourg, UMR7242, ESBS, Strasbourg, France
| | - Véronique Gasser
- CNRS, University of Strasbourg, UMR7242, ESBS, Strasbourg, France
- University of Strasbourg, UMR7242, ESBS, Strasbourg, France
| | - Lauriane Kuhn
- Plateforme Proteomique Strasbourg - Esplanade, Institut de Biologie Moléculaire et Cellulaire, CNRS FR1589, Strasbourg Cedex, France
| | - Sarah Fritsch
- CNRS, University of Strasbourg, UMR7242, ESBS, Strasbourg, France
- University of Strasbourg, UMR7242, ESBS, Strasbourg, France
| | - David E Heinrichs
- Department of Microbiology and Immunology, University of Western Ontario, London, Canada
| | - Isabelle J Schalk
- CNRS, University of Strasbourg, UMR7242, ESBS, Strasbourg, France
- University of Strasbourg, UMR7242, ESBS, Strasbourg, France
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4
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Kim N, Sengupta S, Lee J, Dash U, Kim S, Kim HJ, Song C, Sim T. Synthesis and antibacterial activities of baulamycin A inspired derivatives. Eur J Med Chem 2023; 259:115592. [PMID: 37478559 DOI: 10.1016/j.ejmech.2023.115592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 06/20/2023] [Accepted: 06/23/2023] [Indexed: 07/23/2023]
Abstract
SbnE is an essential enzyme for staphyloferrin B biosynthesis in Staphylococcus aureus. An earlier study showed that natural product baulamycin A has in vitro inhibitory activity against SbnE and antibacterial potency. A SAR study with analogues of baulamycin A was conducted to identify potent inhibitors of SbnE and/or effective antibiotics against MRSA. The results show that selected analogues, including 11, 18, 21, 24a, 24c, 24m and 24n, exhibit single-digit micromolar inhibitory potencies against SbnE (IC50s = 1.81-8.94 μM) and 11, 24m, 24n possess significant activities against both SbnE (IC50s = 4.12-6.12 μM) and bacteria (MICs = 4-32 μg/mL). Biological investigations revealed that these substances possess potent cell wall disruptive activities and that they inhibit siderophore production in MRSA. Among the selected analogues, 7 has excellent antibiotic activities both gram-positive and -negative bacteria (0.5-4 μg/mL). Moreover, these analogues significantly impede biofilm formation in a concentration-dependent manner. Taken together, the results of the investigation provide valuable insight into the nature of novel baulamycin A analogues that have potential efficacy against MRSA owing to their membrane damaging activity and/or inhibitory efficacy against siderophore production.
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Affiliation(s)
- Namkyoung Kim
- KU-KIST Graduate School of Converging Science and Technology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea; Chemical Kinomics Research Center, Korea Institute of Science and Technology (KIST), 5 Hwarangro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea; Severance Biomedical Science Institute, Graduate School of Medicinal Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50, Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Sandip Sengupta
- Chemical Kinomics Research Center, Korea Institute of Science and Technology (KIST), 5 Hwarangro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea; Severance Biomedical Science Institute, Graduate School of Medicinal Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50, Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Jiwon Lee
- Severance Biomedical Science Institute, Graduate School of Medicinal Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50, Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Uttam Dash
- Chemical Kinomics Research Center, Korea Institute of Science and Technology (KIST), 5 Hwarangro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Soojeung Kim
- Department of Chemistry, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Hak Joong Kim
- Department of Chemistry, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Chiman Song
- Chemical Kinomics Research Center, Korea Institute of Science and Technology (KIST), 5 Hwarangro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Taebo Sim
- KU-KIST Graduate School of Converging Science and Technology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea; Chemical Kinomics Research Center, Korea Institute of Science and Technology (KIST), 5 Hwarangro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea; Severance Biomedical Science Institute, Graduate School of Medicinal Science, Brain Korea 21 Project, Yonsei University College of Medicine, 50, Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
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5
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Schalk IJ, Perraud Q. Pseudomonas aeruginosa and its multiple strategies to access iron. Environ Microbiol 2022; 25:811-831. [PMID: 36571575 DOI: 10.1111/1462-2920.16328] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 12/21/2022] [Indexed: 12/27/2022]
Abstract
Pseudomonas aeruginosa is a ubiquitous bacterium found in many natural and man-made environments. It is also a pathogen for plants, animals, and humans. As for almost all living organisms, iron is an essential nutrient for the growth of P. aeruginosa. The bacterium has evolved complex systems to access iron and maintain its homeostasis to survive in diverse natural and dynamic host environments. To access ferric iron, P. aeruginosa is able to produce two siderophores (pyoverdine and pyochelin), as well as use a variety of siderophores produced by other bacteria (mycobactins, enterobactin, ferrioxamine, ferrichrome, vibriobactin, aerobactin, rhizobactin and schizokinen). Furthermore, it can also use citrate, in addition to catecholamine neuromediators and plant-derived mono catechols, as siderophores. The P. aeruginosa genome also encodes three heme-uptake pathways (heme being an iron source) and one ferrous iron acquisition pathway. This review aims to summarize current knowledge concerning the molecular mechanisms involved in all the iron and heme acquisition strategies used by P. aeruginosa.
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Affiliation(s)
- Isabelle J Schalk
- CNRS, UMR7242, ESBS, Strasbourg, France.,University of Strasbourg, UMR7242, ESBS, Strasbourg, France
| | - Quentin Perraud
- CNRS, UMR7242, ESBS, Strasbourg, France.,University of Strasbourg, UMR7242, ESBS, Strasbourg, France
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6
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Oliveira F, Lima T, Correia A, Silva AM, Soares C, Morais S, Weißelberg S, Vilanova M, Rohde H, Cerca N. Involvement of the Iron-Regulated Loci hts and fhuC in Biofilm Formation and Survival of Staphylococcus epidermidis within the Host. Microbiol Spectr 2022; 10:e0216821. [PMID: 35019768 PMCID: PMC8754135 DOI: 10.1128/spectrum.02168-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 12/05/2021] [Indexed: 12/19/2022] Open
Abstract
Staphylococcus epidermidis is a major nosocomial pathogen with a remarkable ability to persist on indwelling medical devices through biofilm formation. Nevertheless, it remains intriguing how this process is efficiently achieved under the host's harsh conditions, where the availability of nutrients, such as essential metals, is scarce. Following our previous identification of two iron-regulated loci putatively involved in iron transport, hts and fhuC, we assessed here their individual contribution to both bacterial physiology and interaction with host immune cells. Single deletions of the hts and fhuC loci led to marked changes in the cell iron content, which were partly detrimental for planktonic growth and strongly affected biofilm formation under iron-restricted conditions. Deletion of each of these two loci did not lead to major changes in S. epidermidis survival within human macrophages or in an ex vivo human blood model of bloodstream infection. However, the lack of either hts or fhuC loci significantly impaired bacterial survival in vivo in a murine model of bacteremia. Collectively, this study establishes, for the first time, the pivotal role of the iron-regulated loci hts and fhuC in S. epidermidis biofilm formation and survival within the host, providing relevant information for the development of new targeted therapeutics against this pathogen. IMPORTANCE Staphylococcus epidermidis is one of the most important nosocomial pathogens and a major cause of central line-associated bloodstream infections. Once in the bloodstream, this bacterium must surpass severe iron restriction in order to survive and establish infection. Surprisingly, very little is known about the iron acquisition mechanisms in this species. This study represents the first report on the involvement of the S. epidermidis iron-regulated loci hts and fhuC in biofilm formation under host relevant conditions and, most importantly, in survival within the host. Ultimately, these findings highlight iron acquisition and these loci in particular, as potential targets for future therapeutic strategies against biofilm-associated S. epidermidis infections.
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Affiliation(s)
- Fernando Oliveira
- Centre of Biological Engineering, LIBRO – Laboratory of Research in Biofilms Rosário Oliveira, University of Minho, Braga, Portugal
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Tânia Lima
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Alexandra Correia
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Ana Margarida Silva
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Cristina Soares
- REQUIMTE-LAQV, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Porto, Portugal
| | - Simone Morais
- REQUIMTE-LAQV, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Porto, Portugal
| | - Samira Weißelberg
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Manuel Vilanova
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC, Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- ICBAS-UP, Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Holger Rohde
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Nuno Cerca
- Centre of Biological Engineering, LIBRO – Laboratory of Research in Biofilms Rosário Oliveira, University of Minho, Braga, Portugal
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7
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Iskandar K, Murugaiyan J, Hammoudi Halat D, Hage SE, Chibabhai V, Adukkadukkam S, Roques C, Molinier L, Salameh P, Van Dongen M. Antibiotic Discovery and Resistance: The Chase and the Race. Antibiotics (Basel) 2022; 11:antibiotics11020182. [PMID: 35203785 PMCID: PMC8868473 DOI: 10.3390/antibiotics11020182] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 01/23/2022] [Accepted: 01/26/2022] [Indexed: 12/14/2022] Open
Abstract
The history of antimicrobial resistance (AMR) evolution and the diversity of the environmental resistome indicate that AMR is an ancient natural phenomenon. Acquired resistance is a public health concern influenced by the anthropogenic use of antibiotics, leading to the selection of resistant genes. Data show that AMR is spreading globally at different rates, outpacing all efforts to mitigate this crisis. The search for new antibiotic classes is one of the key strategies in the fight against AMR. Since the 1980s, newly marketed antibiotics were either modifications or improvements of known molecules. The World Health Organization (WHO) describes the current pipeline as bleak, and warns about the scarcity of new leads. A quantitative and qualitative analysis of the pre-clinical and clinical pipeline indicates that few antibiotics may reach the market in a few years, predominantly not those that fit the innovative requirements to tackle the challenging spread of AMR. Diversity and innovation are the mainstays to cope with the rapid evolution of AMR. The discovery and development of antibiotics must address resistance to old and novel antibiotics. Here, we review the history and challenges of antibiotics discovery and describe different innovative new leads mechanisms expected to replenish the pipeline, while maintaining a promising possibility to shift the chase and the race between the spread of AMR, preserving antibiotic effectiveness, and meeting innovative leads requirements.
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Affiliation(s)
- Katia Iskandar
- Department of Mathématiques Informatique et Télécommunications, Université Toulouse III, Paul Sabatier, INSERM, UMR 1295, 31000 Toulouse, France
- INSPECT-LB: Institut National de Santé Publique, d’Épidémiologie Clinique et de Toxicologie-Liban, Beirut 6573, Lebanon;
- Faculty of Pharmacy, Lebanese University, Beirut 6573, Lebanon
- Correspondence: (K.I.); (D.H.H.)
| | - Jayaseelan Murugaiyan
- Department of Biological Sciences, SRM University–AP, Amaravati 522502, India; (J.M.); (S.A.)
| | - Dalal Hammoudi Halat
- Department of Pharmaceutical Sciences, School of Pharmacy, Lebanese International University, Bekaa Campus, Beirut 1103, Lebanon
- Correspondence: (K.I.); (D.H.H.)
| | - Said El Hage
- Faculty of Medicine, Lebanese University, Beirut 6573, Lebanon;
| | - Vindana Chibabhai
- Division of Clinical Microbiology and Infectious Diseases, School of Pathology, University of the Witwatersrand, Johannesburg 2193, South Africa;
- Microbiology Laboratory, National Health Laboratory Service, Charlotte Maxeke Johannesburg Academic Hospital, Johannesburg 2193, South Africa
| | - Saranya Adukkadukkam
- Department of Biological Sciences, SRM University–AP, Amaravati 522502, India; (J.M.); (S.A.)
| | - Christine Roques
- Laboratoire de Génie Chimique, Department of Bioprocédés et Systèmes Microbiens, Université Paul Sabtier, Toulouse III, UMR 5503, 31330 Toulouse, France;
| | - Laurent Molinier
- Department of Medical Information, Centre Hospitalier Universitaire, INSERM, UMR 1295, Université Paul Sabatier Toulouse III, 31000 Toulouse, France;
| | - Pascale Salameh
- INSPECT-LB: Institut National de Santé Publique, d’Épidémiologie Clinique et de Toxicologie-Liban, Beirut 6573, Lebanon;
- Faculty of Medicine, Lebanese University, Beirut 6573, Lebanon;
- Department of Primary Care and Population Health, University of Nicosia Medical School, Nicosia 2408, Cyprus
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8
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Abstract
Iron (Fe) plays important roles in both essential cellular processes and virulence pathways for many bacteria. Consequently, Fe withholding by the human innate immune system is an effective form of defense against bacterial infection. In this Perspective, we review recent studies that have established a foundation for our understanding of the impact of the metal-sequestering host defense protein calprotectin (CP) on bacterial Fe homeostasis. We also discuss two recently uncovered strategies for bacterial adaptation to Fe withholding by CP. Together, these studies provide insight into how Fe sequestration by CP affects bacterial pathogens that include Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus aureus. Overall, recent studies suggest that Fe withholding by CP may have implications for bacterial survival and virulence in the host, and further explorations that directly address this possibility present an important area for discovery.
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Affiliation(s)
- Adunoluwa O. Obisesan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Emily M. Zygiel
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Elizabeth M. Nolan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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9
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Wang TSA, Chen PL, Chen YCS, Hung HM, Huang JY. Selectively Targeting and Differentiating Vancomycin-Resistant Staphylococcus aureus via Dual Synthetic Fluorescent Probes. ACS Infect Dis 2021; 7:2584-2590. [PMID: 34410687 DOI: 10.1021/acsinfecdis.1c00235] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Many Staphylococcus bacteria are pathogenic and harmful to humans. Noticeably, some Staphylococcus, including vancomycin-resistant S. aureus (VRSA), have become notoriously resistant to antibiotics and have spread rapidly, becoming threats to public health. Here, we designed a dual fluorescent probe scheme combining siderophores and antibiotics as the guiding units to selectively target VRSA and vancomycin-sensitive S. aureus (VSSA) in complex bacterial samples. Siderophore-mediated iron uptake is the key pathway by which S. aureus acquires iron in limited environments. Therefore, the siderophore-derivative probe could differentiate between S. aureus and other bacteria. Moreover, by fine-tuning the vancomycin-derivative probes, we could selectively target only VSSA, further differentiating VRSA and VSSA. Finally, by combining the siderophore-derivative probe and the vancomycin-derivative probe, we successfully targeted and differentiated between VRSA and VSSA in complicated bacterial mixtures.
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Affiliation(s)
| | - Pin-Lung Chen
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan (R.O.C.)
| | - Yi-Chen Sarah Chen
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan (R.O.C.)
| | - Hsuan-Min Hung
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan (R.O.C.)
| | - Jhih-Yi Huang
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan (R.O.C.)
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10
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Butler A, Harder T, Ostrowski AD, Carrano CJ. Photoactive siderophores: Structure, function and biology. J Inorg Biochem 2021; 221:111457. [PMID: 34010741 DOI: 10.1016/j.jinorgbio.2021.111457] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/30/2021] [Accepted: 04/03/2021] [Indexed: 12/17/2022]
Abstract
It is well known that bacteria and fungi have evolved sophisticated systems for acquiring the abundant but biologically inaccessible trace element iron. These systems are based on high affinity Fe(III)-specific binding compounds called siderophores which function to acquire, transport, and process this essential metal ion. Many hundreds of siderophores are now known and their numbers continue to grow. Extensive studies of their isolation, structure, transport, and molecular genetics have been undertaken in the last three decades and have been comprehensively reviewed many times. In this review we focus on a unique subset of siderophores that has only been recognized in the last 20 years, namely those whose iron complexes display photoactivity. This photoactivity, which typically results in the photooxidation of the siderophore ligand with concomitant reduction of Fe(III) to Fe(II), seemingly upsets the siderophore paradigm of forming and transporting only extremely stable Fe(III) complexes into microbial cells. Here we review their structure, synthesis, photochemistry, photoproduct coordination chemistry and explore the potential biological and ecological consequences of this photoactivity.
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Affiliation(s)
- Alison Butler
- Department of Chemistry and Biochemistry University of California, Santa Barbara, CA 93106 United States
| | - Tilmann Harder
- Department of Biology and Chemistry, University of Bremen, and Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Germany
| | | | - Carl J Carrano
- Department of Chemistry and Biochemistry, San Diego State University, United States.
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11
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Southwell JW, Black CM, Duhme-Klair AK. Experimental Methods for Evaluating the Bacterial Uptake of Trojan Horse Antibacterials. ChemMedChem 2020; 16:1063-1076. [PMID: 33238066 DOI: 10.1002/cmdc.202000806] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Indexed: 01/10/2023]
Abstract
The field of antibacterial siderophore conjugates, referred to as Trojan Horse antibacterials, has received increasing attention in recent years, driven by the rise of antimicrobial resistance. Trojan Horse antibacterials offer an opportunity to exploit the specific pathways present in bacteria for active iron uptake, potentially allowing the drugs to bypass membrane-associated resistance mechanisms. Hence, the Trojan Horse approach might enable the redesigning of old antibiotics and the development of antibacterials that target specific pathogens. Critical parts of evaluating such Trojan Horse antibacterials and improving their design are the quantification of their bacterial uptake and the identification of the pathways by which this occurs. In this minireview, we highlight a selection of the biological and chemical methods used to study the uptake of Trojan Horse antibacterials, exemplified with case studies, some of which have led to drug candidates in clinical development or approved antibiotics.
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Affiliation(s)
- James W Southwell
- Department of Chemistry, University of York, Heslington, North Yorkshire, YO10 5DD, UK
| | - Conor M Black
- Department of Chemistry, University of York, Heslington, North Yorkshire, YO10 5DD, UK
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12
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Zhang Y, Sen S, Giedroc DP. Iron Acquisition by Bacterial Pathogens: Beyond Tris-Catecholate Complexes. Chembiochem 2020; 21:1955-1967. [PMID: 32180318 PMCID: PMC7367709 DOI: 10.1002/cbic.201900778] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 03/06/2020] [Indexed: 12/11/2022]
Abstract
Sequestration of the essential nutrient iron from bacterial invaders that colonize the vertebrate host is a central feature of nutritional immunity and the "fight over transition metals" at the host-pathogen interface. The iron quota for many bacterial pathogens is large, as iron enzymes often make up a significant share of the metalloproteome. Iron enzymes play critical roles in respiration, energy metabolism, and other cellular processes by catalyzing a wide range of oxidation-reduction, electron transfer, and oxygen activation reactions. In this Concept article, we discuss recent insights into the diverse ways that bacterial pathogens acquire this essential nutrient, beyond the well-characterized tris-catecholate FeIII complexes, in competition and cooperation with significant host efforts to cripple these processes. We also discuss pathogen strategies to adapt their metabolism to less-than-optimal iron concentrations, and briefly speculate on what might be an integrated adaptive response to the concurrent limitation of both iron and zinc in the infected host.
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Affiliation(s)
- Yifan Zhang
- Department of Chemistry, Indiana University, Bloomington, IN 47405-7102, USA
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405-7102, USA
| | - Sambuddha Sen
- Department of Chemistry, Indiana University, Bloomington, IN 47405-7102, USA
| | - David P Giedroc
- Department of Chemistry, Indiana University, Bloomington, IN 47405-7102, USA
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405-7102, USA
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13
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Endicott N, Rivera GSM, Yang J, Wencewicz TA. Emergence of Ferrichelatase Activity in a Siderophore-Binding Protein Supports an Iron Shuttle in Bacteria. ACS CENTRAL SCIENCE 2020; 6:493-506. [PMID: 32341999 PMCID: PMC7181320 DOI: 10.1021/acscentsci.9b01257] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Indexed: 05/08/2023]
Abstract
Siderophores are small-molecule high-affinity multidentate chelators selective for ferric iron that are produced by pathogenic microbes to aid in nutrient sequestration and enhance virulence. In Gram-positive bacteria, the currently accepted paradigm in siderophore-mediated iron acquisition is that effluxed metal-free siderophores extract ferric iron from biological sources and the resulting ferric siderophore complex undergoes diffusion-controlled association with a surface-displayed siderophore-binding protein (SBP) followed by ABC permease-mediated translocation across the cell envelope powered by ATP hydrolysis. Here we show that a more efficient paradigm is possible in Gram-positive bacteria where extracellular metal-free siderophores associate directly with apo-SBPs on the cell surface and serve as non-covalent cofactors that enable the holo-SBPs to non-reductively extract ferric iron directly from host metalloproteins with so-called "ferrichelatase" activity. The resulting SBP-bound ferric siderophore complex is ready for import through an associated membrane permease and enzymatic turnover is achieved through cofactor replacement from the readily available pool of extracellular siderophores. This new "iron shuttle" model closes a major knowledge gap in microbial iron acquisition and defines new roles of the siderophore and SBP as cofactor and enzyme, respectively, in addition to the classically accepted roles as a transport substrate and receptor pair. We propose the formal name "siderophore-dependent ferrichelatases" for this new class of catalytic SBPs.
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14
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Marchetti M, De Bei O, Bettati S, Campanini B, Kovachka S, Gianquinto E, Spyrakis F, Ronda L. Iron Metabolism at the Interface between Host and Pathogen: From Nutritional Immunity to Antibacterial Development. Int J Mol Sci 2020; 21:E2145. [PMID: 32245010 PMCID: PMC7139808 DOI: 10.3390/ijms21062145] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 03/16/2020] [Accepted: 03/17/2020] [Indexed: 02/08/2023] Open
Abstract
Nutritional immunity is a form of innate immunity widespread in both vertebrates and invertebrates. The term refers to a rich repertoire of mechanisms set up by the host to inhibit bacterial proliferation by sequestering trace minerals (mainly iron, but also zinc and manganese). This strategy, selected by evolution, represents an effective front-line defense against pathogens and has thus inspired the exploitation of iron restriction in the development of innovative antimicrobials or enhancers of antimicrobial therapy. This review focuses on the mechanisms of nutritional immunity, the strategies adopted by opportunistic human pathogen Staphylococcus aureus to circumvent it, and the impact of deletion mutants on the fitness, infectivity, and persistence inside the host. This information finally converges in an overview of the current development of inhibitors targeting the different stages of iron uptake, an as-yet unexploited target in the field of antistaphylococcal drug discovery.
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Affiliation(s)
- Marialaura Marchetti
- Interdepartmental Center Biopharmanet-TEC, University of Parma, 43124 Parma, Italy; (M.M.); (S.B.)
| | - Omar De Bei
- Department of Food and Drug, University of Parma, 43124 Parma, Italy; (O.D.B.); (B.C.)
| | - Stefano Bettati
- Interdepartmental Center Biopharmanet-TEC, University of Parma, 43124 Parma, Italy; (M.M.); (S.B.)
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy
- Institute of Biophysics, National Research Council, 56124 Pisa, Italy
- National Institute of Biostructures and Biosystems, 00136 Rome, Italy
| | - Barbara Campanini
- Department of Food and Drug, University of Parma, 43124 Parma, Italy; (O.D.B.); (B.C.)
| | - Sandra Kovachka
- Department of Drug Science and Technology, University of Turin, 10125 Turin, Italy; (S.K.); (E.G.); (F.S.)
| | - Eleonora Gianquinto
- Department of Drug Science and Technology, University of Turin, 10125 Turin, Italy; (S.K.); (E.G.); (F.S.)
| | - Francesca Spyrakis
- Department of Drug Science and Technology, University of Turin, 10125 Turin, Italy; (S.K.); (E.G.); (F.S.)
| | - Luca Ronda
- Interdepartmental Center Biopharmanet-TEC, University of Parma, 43124 Parma, Italy; (M.M.); (S.B.)
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy
- Institute of Biophysics, National Research Council, 56124 Pisa, Italy
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15
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Garzón-Posse F, Quevedo-Acosta Y, Mahecha-Mahecha C, Acosta-Guzmán P. Recent Progress in the Synthesis of Naturally Occurring Siderophores. European J Org Chem 2019. [DOI: 10.1002/ejoc.201901257] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Fabián Garzón-Posse
- Laboratory of Organic Synthesis; Bio and Organocatalysis; Universidad de los Andes; Cra 1 No. 18A-12 Q:305 111711 Bogotá Colombia
| | - Yovanny Quevedo-Acosta
- Laboratory of Organic Synthesis; Bio and Organocatalysis Chemistry Department; Universidad de los Andes; Cra 1 No. 18A-12 Q:305 111711 Bogotá Colombia
- Institute of Chemistry; Bio and Organocatalysis Chemistry Department; State University of Campinas; Rua Monteiro Lobato 270 13083-862 Campinas Brazil
| | - Camilo Mahecha-Mahecha
- Laboratory of Organic Synthesis; Bio and Organocatalysis Chemistry Department; Universidad de los Andes; Cra 1 No. 18A-12 Q:305 111711 Bogotá Colombia
| | - Paola Acosta-Guzmán
- Laboratory of Organic Synthesis; Bio and Organocatalysis Chemistry Department; Universidad de los Andes; Cra 1 No. 18A-12 Q:305 111711 Bogotá Colombia
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16
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Zhang J, Zhao T, Yang R, Siridechakorn I, Wang S, Guo Q, Bai Y, Shen HC, Lei X. De novo synthesis, structural assignment and biological evaluation of pseudopaline, a metallophore produced by Pseudomonas aeruginosa. Chem Sci 2019; 10:6635-6641. [PMID: 31367316 PMCID: PMC6625496 DOI: 10.1039/c9sc01405e] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 05/27/2019] [Indexed: 12/15/2022] Open
Abstract
Pseudopaline is an opine carboxylate metallophore produced by Pseudomonas aeruginosa for harvesting divalent metals. However, the structure of pseudopaline is not fully elucidated. Herein, we report the first de novo total synthesis and isolation of pseudopaline, which allows unambiguous determination and confirmation of both the absolute and the relative configuration of the natural product. The synthesis highlights an efficient and stereocontrolled route using the asymmetric Tsuji-Trost reaction as the key step. The preliminary structure-activity relationship study indicated that one pseudopaline derivative shows comparable activity to pseudopaline. Moreover, a pseudopaline-fluorescein conjugate was prepared and evaluated, which confirmed that pseudopaline could be transported in the bacteria. Since the metal acquisition by P. aeruginosa is crucial for its ability to cause diseases, our extensive structural and functional studies of pseudopaline may pave the way for developing new therapeutic strategies such as the "Trojan horse" antibiotic conjugate against P. aeruginosa.
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Affiliation(s)
- Jian Zhang
- Beijing National Laboratory for Molecular Sciences , Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education , Department of Chemical Biology , College of Chemistry and Molecular Engineering , Synthetic and Functional Biomolecules Center , Peking-Tsinghua Center for Life Sciences , Peking University , Beijing 100871 , China .
| | - Tianhu Zhao
- Beijing National Laboratory for Molecular Sciences , Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education , Department of Chemical Biology , College of Chemistry and Molecular Engineering , Synthetic and Functional Biomolecules Center , Peking-Tsinghua Center for Life Sciences , Peking University , Beijing 100871 , China .
| | - Rongwen Yang
- Beijing National Laboratory for Molecular Sciences , Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education , Department of Chemical Biology , College of Chemistry and Molecular Engineering , Synthetic and Functional Biomolecules Center , Peking-Tsinghua Center for Life Sciences , Peking University , Beijing 100871 , China .
| | - Ittipon Siridechakorn
- Beijing National Laboratory for Molecular Sciences , Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education , Department of Chemical Biology , College of Chemistry and Molecular Engineering , Synthetic and Functional Biomolecules Center , Peking-Tsinghua Center for Life Sciences , Peking University , Beijing 100871 , China .
| | - Sanshan Wang
- Beijing National Laboratory for Molecular Sciences , Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education , Department of Chemical Biology , College of Chemistry and Molecular Engineering , Synthetic and Functional Biomolecules Center , Peking-Tsinghua Center for Life Sciences , Peking University , Beijing 100871 , China .
| | - Qianqian Guo
- Beijing National Laboratory for Molecular Sciences , Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education , Department of Chemical Biology , College of Chemistry and Molecular Engineering , Synthetic and Functional Biomolecules Center , Peking-Tsinghua Center for Life Sciences , Peking University , Beijing 100871 , China .
| | - Yingjie Bai
- Beijing National Laboratory for Molecular Sciences , Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education , Department of Chemical Biology , College of Chemistry and Molecular Engineering , Synthetic and Functional Biomolecules Center , Peking-Tsinghua Center for Life Sciences , Peking University , Beijing 100871 , China .
| | - Hong C Shen
- Roche Innovation Center Shanghai , Roche Pharma Research & Early Development , Shanghai 201203 , China
| | - Xiaoguang Lei
- Beijing National Laboratory for Molecular Sciences , Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education , Department of Chemical Biology , College of Chemistry and Molecular Engineering , Synthetic and Functional Biomolecules Center , Peking-Tsinghua Center for Life Sciences , Peking University , Beijing 100871 , China .
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17
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Abouelhassan Y, Garrison AT, Yang H, Chávez-Riveros A, Burch GM, Huigens RW. Recent Progress in Natural-Product-Inspired Programs Aimed To Address Antibiotic Resistance and Tolerance. J Med Chem 2019; 62:7618-7642. [PMID: 30951303 DOI: 10.1021/acs.jmedchem.9b00370] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Bacteria utilize multiple mechanisms that enable them to gain or acquire resistance to antibiotic therapies during the treatment of infections. In addition, bacteria form biofilms which are surface-attached communities of enriched populations containing persister cells encased within a protective extracellular matrix of biomolecules, leading to chronic and recurring antibiotic-tolerant infections. Antibiotic resistance and tolerance are major global problems that require innovative therapeutic strategies to address the challenges associated with pathogenic bacteria. Historically, natural products have played a critical role in bringing new therapies to the clinic to treat life-threatening bacterial infections. This Perspective provides an overview of antibiotic resistance and tolerance and highlights recent advances (chemistry, biology, drug discovery, and development) from various research programs involved in the discovery of new antibacterial agents inspired by a diverse series of natural product antibiotics.
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Affiliation(s)
- Yasmeen Abouelhassan
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| | - Aaron T Garrison
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| | - Hongfen Yang
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| | - Alejandra Chávez-Riveros
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| | - Gena M Burch
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| | - Robert W Huigens
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
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18
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Conroy BS, Grigg JC, Kolesnikov M, Morales LD, Murphy MEP. Staphylococcus aureus heme and siderophore-iron acquisition pathways. Biometals 2019; 32:409-424. [PMID: 30911924 DOI: 10.1007/s10534-019-00188-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 03/18/2019] [Indexed: 11/24/2022]
Abstract
Staphylococcus aureus is a versatile opportunistic human pathogen. Infection by this bacterium requires uptake of iron from the human host, but iron is highly restricted in this environment. Staphylococcus aureus iron sufficiency is achieved primarily through uptake of heme and high-affinity iron chelators, known as siderophores. Two siderophores (staphyloferrins) are produced and secreted by S. aureus into the extracellular environment to capture iron. Staphylococcus aureus expresses specific uptake systems for staphyloferrins and more general uptake systems for siderophores produced by other microorganisms. The S. aureus heme uptake system uses highly-specific cell surface receptors to extract heme from hemoglobin and hemoglobin-haptoglobin complexes for transport into the cytoplasm where it is degraded to liberate iron. Initially thought to be independent systems, recent findings indicate that these iron uptake pathways intersect. IruO is a reductase that releases iron from heme and some ferric-siderophores. Moreover, multifunctional SbnI produces a precursor for staphyloferrin B biosynthesis, and also binds heme to regulate expression of the staphyloferrin B biosynthesis pathway. Intersection of the S. aureus iron uptake pathways is hypothesized to be important for rapid adaptation to available iron sources. Components of the heme and siderophore uptake systems are currently being targeted in the development of therapeutics against S. aureus.
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Affiliation(s)
- Brigid S Conroy
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, V6T 1Z3, Canada
| | - Jason C Grigg
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, V6T 1Z3, Canada
| | - Maxim Kolesnikov
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, V6T 1Z3, Canada
| | - L Daniela Morales
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, V6T 1Z3, Canada
| | - Michael E P Murphy
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, V6T 1Z3, Canada.
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19
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Bailey DC, Alexander E, Rice MR, Drake EJ, Mydy LS, Aldrich CC, Gulick AM. Structural and functional delineation of aerobactin biosynthesis in hypervirulent Klebsiella pneumoniae. J Biol Chem 2018; 293:7841-7852. [PMID: 29618511 DOI: 10.1074/jbc.ra118.002798] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 03/30/2018] [Indexed: 12/17/2022] Open
Abstract
Aerobactin, a citryl-hydroxamate siderophore, is produced by a number of pathogenic Gram-negative bacteria to aid in iron assimilation. Interest in this well-known siderophore was reignited by recent investigations suggesting that it plays a key role in mediating the enhanced virulence of a hypervirulent pathotype of Klebsiella pneumoniae (hvKP). In contrast to classical opportunistic strains of K. pneumoniae, hvKP causes serious life-threatening infections in previously healthy individuals in the community. Multiple contemporary reports have confirmed fears that the convergence of multidrug-resistant and hvKP pathotypes has led to the evolution of a highly transmissible, drug-resistant, and virulent "super bug." Despite hvKP harboring four distinct siderophore operons, knocking out production of only aerobactin led to a significant attenuation of virulence. Herein, we continue our structural and functional studies on the biosynthesis of this crucial virulence factor. In vivo heterologous production and in vitro reconstitution of aerobactin biosynthesis from hvKP was carried out, demonstrating the specificity, stereoselectivity, and kinetic throughput of the complete pathway. Additionally, we present a steady-state kinetic analysis and the X-ray crystal structure of the second aerobactin synthetase IucC, as well as describe a surface entropy reduction strategy that was employed for structure determination. Finally, we show solution X-ray scattering data that support a unique dimeric quaternary structure for IucC. These new insights into aerobactin assembly will help inform potential antivirulence strategies and advance our understanding of siderophore biosynthesis.
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Affiliation(s)
- Daniel C Bailey
- From the Department of Structural Biology, The Jacobs School of Medicine & Biomedical Sciences, State University of New York, Buffalo, New York 14203.,the Hauptman-Woodward Medical Research Institute, Buffalo, New York 14203, and
| | - Evan Alexander
- the Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455
| | - Matthew R Rice
- the Hauptman-Woodward Medical Research Institute, Buffalo, New York 14203, and
| | - Eric J Drake
- From the Department of Structural Biology, The Jacobs School of Medicine & Biomedical Sciences, State University of New York, Buffalo, New York 14203.,the Hauptman-Woodward Medical Research Institute, Buffalo, New York 14203, and
| | - Lisa S Mydy
- From the Department of Structural Biology, The Jacobs School of Medicine & Biomedical Sciences, State University of New York, Buffalo, New York 14203.,the Hauptman-Woodward Medical Research Institute, Buffalo, New York 14203, and
| | - Courtney C Aldrich
- the Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455
| | - Andrew M Gulick
- From the Department of Structural Biology, The Jacobs School of Medicine & Biomedical Sciences, State University of New York, Buffalo, New York 14203, .,the Hauptman-Woodward Medical Research Institute, Buffalo, New York 14203, and
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20
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Nakashige TG, Nolan EM. Human calprotectin affects the redox speciation of iron. Metallomics 2017; 9:1086-1095. [PMID: 28561859 DOI: 10.1039/c7mt00044h] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We report that the metal-sequestering human host-defense protein calprotectin (CP, S100A8/S100A9 oligomer) affects the redox speciation of iron (Fe) in bacterial growth media and buffered aqueous solution. Under aerobic conditions and in the absence of an exogenous reducing agent, CP-Ser (S100A8(C42S)/S100A9(C3S) oligomer) depletes Fe from three different bacterial growth media preparations over a 48 h timeframe (T = 30 °C). The presence of the reducing agent β-mercaptoethanol accelerates this process and allows CP-Ser to deplete Fe over a ≈1 h timeframe. Fe-depletion assays performed with metal-binding-site variants of CP-Ser show that the hexahistidine (His6) site, which coordinates Fe(ii) with high affinity, is required for Fe depletion. An analysis of Fe redox speciation in buffer containing Fe(iii) citrate performed under aerobic conditions demonstrates that CP-Ser causes a time-dependent increase in the [Fe(ii)]/[Fe(iii)] ratio. Taken together, these results indicate that the hexahistidine site of CP stabilizes Fe(ii) and thereby shifts the redox equilibrium of Fe to the reduced ferrous state under aerobic conditions. We also report that the presence of bacterial metabolites affects the Fe-depleting activity of CP-Ser. Supplementation of bacterial growth media with an Fe(iii)-scavenging siderophore (enterobactin, staphyloferrin B, or desferrioxamine B) attenuates the Fe-depleting activity of CP-Ser. This result indicates that formation of Fe(iii)-siderophore complexes blocks CP-mediated reduction of Fe(iii) and hence the ability of CP to coordinate Fe(ii). In contrast, the presence of pyocyanin (PYO), a redox-cycling phenazine produced by Pseudomonas aeruginosa that reduces Fe(iii) to Fe(ii), accelerates Fe depletion by CP-Ser under aerobic conditions. These findings indicate that the presence of microbial metabolites that contribute to metal homeostasis at the host/pathogen interface can affect the metal-sequestering function of CP.
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Affiliation(s)
- Toshiki G Nakashige
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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21
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Sengupta S, Bae M, Oh DC, Dash U, Kim HJ, Song WY, Shin I, Sim T. Structural Revision of Baulamycin A and Structure-Activity Relationships of Baulamycin A Derivatives. J Org Chem 2017; 82:12947-12966. [PMID: 28903000 DOI: 10.1021/acs.joc.7b01719] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Total synthesis of the proposed structure of baulamycin A was performed. The spectral properties of the synthetic compound differ from those reported for the natural product. On the basis of comprehensive NMR study, we proposed two other possible structures for natural baulamycin A. Total syntheses of these two substances were performed, which enabled assignment of the correct structure of baulamycin A. Key features of the convergent and fully stereocontrolled route include Evans Aldol and Brown allylation reactions to construct the left fragment, a prolinol amide-derived alkylation/desymmetrization to install the methyl-substituted centers in the right fragment, and finally, a Carreira alkynylation to join both fragments. In addition, we have determined the inhibitory activities of novel baulamycin A derivatives against the enzyme SbnE. This SAR study provides useful insight into the design of novel SbnE inhibitors that overcome the drug resistance of pathogens, which cause life-threatening infections.
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Affiliation(s)
- Sandip Sengupta
- Chemical Kinomics Research Center, Korea Institute of Science and Technology (KIST) , 5 Hwarangro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea
| | - Munhyung Bae
- Natural Products Research Institute, College of Pharmacy, Seoul National University , 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Dong-Chan Oh
- Natural Products Research Institute, College of Pharmacy, Seoul National University , 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Uttam Dash
- Chemical Kinomics Research Center, Korea Institute of Science and Technology (KIST) , 5 Hwarangro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea
| | | | | | | | - Taebo Sim
- Chemical Kinomics Research Center, Korea Institute of Science and Technology (KIST) , 5 Hwarangro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea
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22
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Besserglick J, Olshvang E, Szebesczyk A, Englander J, Levinson D, Hadar Y, Gumienna-Kontecka E, Shanzer A. Ferrichrome Has Found Its Match: Biomimetic Analogues with Diversified Activity Map Discrete Microbial Targets. Chemistry 2017; 23:13181-13191. [DOI: 10.1002/chem.201702647] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Indexed: 12/17/2022]
Affiliation(s)
- Jenny Besserglick
- Department of Organic Chemistry; The Weizmann Institute of Science; Rehovot 7610001 Israel
| | - Evgenia Olshvang
- Department of Organic Chemistry; The Weizmann Institute of Science; Rehovot 7610001 Israel
| | - Agnieszka Szebesczyk
- Faculty of Chemistry; University of Wrocław; F. Joliot-Curie 14 50-383 Wrocław Poland
| | - Joseph Englander
- Department of Organic Chemistry; The Weizmann Institute of Science; Rehovot 7610001 Israel
| | - Dana Levinson
- Department of Plant Pathology and Microbiology; The R.H. Smith Faculty of Agriculture Food and Environment; The Hebrew University of Jerusalem; Rehovot 7610001 Israel
| | - Yitzhak Hadar
- Department of Plant Pathology and Microbiology; The R.H. Smith Faculty of Agriculture Food and Environment; The Hebrew University of Jerusalem; Rehovot 7610001 Israel
| | | | - Abraham Shanzer
- Department of Organic Chemistry; The Weizmann Institute of Science; Rehovot 7610001 Israel
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23
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Endicott NP, Lee E, Wencewicz TA. Structural Basis for Xenosiderophore Utilization by the Human Pathogen Staphylococcus aureus. ACS Infect Dis 2017; 3:542-553. [PMID: 28505405 DOI: 10.1021/acsinfecdis.7b00036] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Staphylococcus aureus produces a cocktail of metallophores (staphylopine, staphyloferrin A, and staphyloferrin B) to scavenge transition metals during infection of a host. In addition, S. aureus displays the extracellular surface lipoproteins FhuD1 and FhuD2 along with the ABC transporter complex FhuCBG to facilitate the use of hydroxamate xenosiderophores such as desferrioxamine B (DFOB) for iron acquisition. DFOB is used as a chelation therapy to treat human iron overload diseases and has been linked to an increased risk of S. aureus infections. We used a panel of synthetic DFOB analogs and a FhuD2-selective trihydroxamate sideromycin to probe xenosiderophore utilization in S. aureus and establish structure-activity relationships for Fe(III) binding, FhuD2 binding, S. aureus growth promotion, and competition for S. aureus cell entry. Fe(III) binding assays and FhuD2 intrinsic fluorescence quenching experiments revealed that diverse chemical modifications of the terminal ends of linear ferrioxamine siderophores influences Fe(III) affinity but not FhuD2 binding. Siderophore-sideromycin competition assays and xenosiderophore growth promotion assays revealed that S. aureus SG511 and ATCC 11632 can distinguish between competing siderophores based exclusively on net charge of the siderophore-Fe(III) complex. Our work provides a roadmap for tuning hydroxamate xenosiderophore scaffolds to suppress (net negative charge) or enhance (net positive or neutral charge) uptake by S. aureus for applications in metal chelation therapy and siderophore-mediated antibiotic delivery, respectively.
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Affiliation(s)
- Nathaniel P. Endicott
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, Missouri 63130, United States
| | - Eries Lee
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, Missouri 63130, United States
| | - Timothy A. Wencewicz
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, Missouri 63130, United States
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24
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Tan L, Tao Y, Wang T, Zou F, Zhang S, Kou Q, Niu A, Chen Q, Chu W, Chen X, Wang H, Yang Y. Discovery of Novel Pyridone-Conjugated Monosulfactams as Potent and Broad-Spectrum Antibiotics for Multidrug-Resistant Gram-Negative Infections. J Med Chem 2017; 60:2669-2684. [DOI: 10.1021/acs.jmedchem.6b01261] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Liang Tan
- State
Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunliang Tao
- College
of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, Zhejiang Province 314001, China
| | - Ting Wang
- Department
of Microbiology, Sichuan Primed Bio-Tech Group Co., Ltd., Chengdu, Sichuan Province 610041, China
| | - Feng Zou
- Department
of Microbiology, Sichuan Primed Bio-Tech Group Co., Ltd., Chengdu, Sichuan Province 610041, China
| | - Shuhua Zhang
- Department
of Microbiology, Sichuan Primed Bio-Tech Group Co., Ltd., Chengdu, Sichuan Province 610041, China
| | - Qunhuan Kou
- State
Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ao Niu
- Department
of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu Province 210009, China
| | - Qian Chen
- State
Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenjing Chu
- State
Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoyan Chen
- State
Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haidong Wang
- College
of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, Zhejiang Province 314001, China
| | - Yushe Yang
- State
Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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25
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Song WY, Jeong D, Kim J, Lee MW, Oh MH, Kim HJ. Key Structural Elements for Cellular Uptake of Acinetobactin, a Major Siderophore of Acinetobacter baumannii. Org Lett 2017; 19:500-503. [PMID: 28102683 DOI: 10.1021/acs.orglett.6b03671] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Acinetobactin is a major siderophore utilized by the human pathogen Acinetobacter baumannii. The rapid acquisition of drug resistance by A. baumannii has garnered concern globally. Herein, acinetobactin and systematically generated analogues were prepared and characterized; the binding and cellular delivery of Fe(III) by the analogues were evaluated. This investigation not only led to the clarification of the physiologically relevant acinetobactin structure but also revealed several key structural elements for its functionality as a siderophore.
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Affiliation(s)
- Woon Young Song
- Department of Chemistry, Korea University , 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Dawa Jeong
- Department of Chemistry, Korea University , 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Jimin Kim
- Department of Chemistry, Korea University , 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Min Wook Lee
- Department of Chemistry, Korea University , 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Man Hwan Oh
- Department of Nanobiomedical Science, Dankook University , Cheonan 31116, Republic of Korea
| | - Hak Joong Kim
- Department of Chemistry, Korea University , 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
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26
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Neumann W, Gulati A, Nolan EM. Metal homeostasis in infectious disease: recent advances in bacterial metallophores and the human metal-withholding response. Curr Opin Chem Biol 2016; 37:10-18. [PMID: 27992799 DOI: 10.1016/j.cbpa.2016.09.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Accepted: 09/14/2016] [Indexed: 10/20/2022]
Abstract
A tug-of-war between the mammalian host and bacterial pathogen for nutrients, including first-row transition metals (e.g. Mn, Fe, Zn), occurs during infection. Here we present recent advances about three metal-chelating metabolites that bacterial pathogens deploy when invading the host: staphylopine, staphyloferrin B, and enterobactin. These highlights provide new insights into the mechanisms of bacterial metal acquisition and regulation, as well as the contributions of host-defense proteins during the human innate immune response. The studies also underscore that the chemical composition of the microenvironment at an infection site can influence bacterial pathogenesis and the innate immune system.
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Affiliation(s)
- Wilma Neumann
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Anmol Gulati
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Elizabeth M Nolan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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27
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New antibiotics from Nature’s chemical inventory. Bioorg Med Chem 2016; 24:6227-6252. [DOI: 10.1016/j.bmc.2016.09.014] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/07/2016] [Indexed: 01/07/2023]
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28
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A facile label-free electrochemiluminescent biosensor for specific detection of Staphylococcus aureus utilizing the binding between immunoglobulin G and protein A. Talanta 2016; 153:401-6. [DOI: 10.1016/j.talanta.2016.03.043] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 03/07/2016] [Accepted: 03/12/2016] [Indexed: 12/22/2022]
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29
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Su Q, Guan T, He Y, Lv H. Siderophore Biosynthesis Governs the Virulence of Uropathogenic Escherichia coli by Coordinately Modulating the Differential Metabolism. J Proteome Res 2016; 15:1323-32. [DOI: 10.1021/acs.jproteome.6b00061] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Qiao Su
- The Laboratory
for Functional
Omics and Innovative Chinese Medicine, Innovative Drug Research Center, Chongqing University, Chongqing 401331, P.R. China
| | - Tianbing Guan
- The Laboratory
for Functional
Omics and Innovative Chinese Medicine, Innovative Drug Research Center, Chongqing University, Chongqing 401331, P.R. China
| | - Yan He
- The Laboratory
for Functional
Omics and Innovative Chinese Medicine, Innovative Drug Research Center, Chongqing University, Chongqing 401331, P.R. China
| | - Haitao Lv
- The Laboratory
for Functional
Omics and Innovative Chinese Medicine, Innovative Drug Research Center, Chongqing University, Chongqing 401331, P.R. China
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30
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Shapiro JA, Wencewicz TA. Acinetobactin Isomerization Enables Adaptive Iron Acquisition in Acinetobacter baumannii through pH-Triggered Siderophore Swapping. ACS Infect Dis 2016; 2:157-68. [PMID: 27624967 DOI: 10.1021/acsinfecdis.5b00145] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Pathogenic strains of Acinetobacter baumannii excrete multiple siderophores that enhance iron scavenging from host sources. The oxazoline siderophore pre-acinetobactin undergoes an unusual non-enzymatic isomerization, producing the isoxazolidinone acinetobactin. In this study, we explored the kinetics, mechanism, and biological consequence of this siderophore swapping. Pre-acinetobactin is excreted to the extracellular space where the isomerization to acinetobactin occurs with a pH-rate profile consistent with 5-exo-tet cyclization at C5' with clean stereochemical inversion. Pre-acinetobactin persists at pH <6, and acinetobactin is rapidly formed at pH >7, matching each siderophore's pH preference for iron(III) chelation and A. baumannii growth promotion. Acinetobactin isomerization provides two siderophores for the price of one, enabling A. baumannii to sequester iron over a broad pH range likely to be encountered during the course of an infection.
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Affiliation(s)
- Justin A. Shapiro
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, Missouri 63130, United States
| | - Timothy A. Wencewicz
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, Missouri 63130, United States
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