1
|
Sengupta S, Pabbaraja S, Mehta G. Natural products from the human microbiome: an emergent frontier in organic synthesis and drug discovery. Org Biomol Chem 2024; 22:4006-4030. [PMID: 38669195 DOI: 10.1039/d4ob00236a] [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: 04/28/2024]
Abstract
Often referred to as the "second genome", the human microbiome is at the epicenter of complex inter-habitat biochemical networks like the "gut-brain axis", which has emerged as a significant determinant of cognition, overall health and well-being, as well as resistance to antibiotics and susceptibility to diseases. As part of a broader understanding of the nexus between the human microbiome, diseases and microbial interactions, whether encoded secondary metabolites (natural products) play crucial signalling roles has been the subject of intense scrutiny in the recent past. A major focus of these activities involves harvesting the genomic potential of the human microbiome via bioinformatics guided genome mining and culturomics. Through these efforts, an impressive number of structurally intriguing antibiotics, with enhanced chemical diversity vis-à-vis conventional antibiotics have been isolated from human commensal bacteria, thereby generating considerable interest in their total synthesis and expanding their therapeutic space for drug discovery. These developments augur well for the discovery of new drugs and antibiotics, particularly in the context of challenges posed by mycobacterial resistance and emerging new diseases. The current landscape of various synthetic campaigns and drug discovery initiatives on antibacterial natural products from the human microbiome is captured in this review with an intent to stimulate further activities in this interdisciplinary arena among the new generation.
Collapse
Affiliation(s)
- Saumitra Sengupta
- School of Chemistry, University of Hyderabad, Hyderabad-500046, India.
- Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad-500007, India
| | - Srihari Pabbaraja
- Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad-500007, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Goverdhan Mehta
- School of Chemistry, University of Hyderabad, Hyderabad-500046, India.
| |
Collapse
|
2
|
Kim HR, Kim J, Yu JS, Lee BS, Kim KH, Kim CS. Isolation, structure elucidation, total synthesis, and biosynthesis of dermazolium A, an antibacterial imidazolium metabolite of a vaginal bacterium Dermabacter vaginalis. Arch Pharm Res 2023; 46:35-43. [PMID: 36642761 DOI: 10.1007/s12272-022-01424-z] [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: 11/14/2022] [Accepted: 12/27/2022] [Indexed: 01/17/2023]
Abstract
Dermabacter vaginalis is a human-derived bacterium isolated from vaginal fluid of a Korean female in 2016. Although several human-related species in Dermabacter genus have been reported there are few studies on their bioactive metabolites. Dermazolium A (1), a rare imidazolium metabolite, was isolated from D. vaginalis along with five known metabolites (2-6) and their chemical structures were determined by NMR, HRMS, and MS/MS data analysis. Feeding experiments using predicted precursors and biomimetic total synthesis of 1 corroborated its structure and led to suggestion of biosynthetic pathway of 1. Antibacterial tests on the isolated compounds showed that 1 is a mild antibacterial agent with MIC values of 41 µg/mL against methicillin-resistant Staphylococcus aureus (MRSA) USA300, Lacticaseibacillus paracasei subsp. paracasei KCTC 3510 and Brevibacterium epidermidis KCTC 3090.
Collapse
Affiliation(s)
- Hye Ryeong Kim
- Department of Biopharmaceutical Convergence, Sungkyunkwan University, 16419, Suwon, Republic of Korea
| | - Jonghwan Kim
- Department of Biopharmaceutical Convergence, Sungkyunkwan University, 16419, Suwon, Republic of Korea
| | - Jae Sik Yu
- School of Pharmacy, Sungkyunkwan University, 16419, Suwon, Republic of Korea.,Department of Integrative Biological Sciences and Industry, Sejong University, 05006, Seoul, Republic of Korea
| | - Bum Soo Lee
- School of Pharmacy, Sungkyunkwan University, 16419, Suwon, Republic of Korea
| | - Ki Hyun Kim
- School of Pharmacy, Sungkyunkwan University, 16419, Suwon, Republic of Korea
| | - Chung Sub Kim
- Department of Biopharmaceutical Convergence, Sungkyunkwan University, 16419, Suwon, Republic of Korea. .,School of Pharmacy, Sungkyunkwan University, 16419, Suwon, Republic of Korea.
| |
Collapse
|
3
|
Kawashima A, Kiriya M, En J, Tanigawa K, Nakamura Y, Fujiwara Y, Luo Y, Maruyama K, Watanabe S, Goto M, Suzuki K. Genome-wide screening identified SEC61A1 as an essential factor for mycolactone-dependent apoptosis in human premonocytic THP-1 cells. PLoS Negl Trop Dis 2022; 16:e0010672. [PMID: 35939511 PMCID: PMC9387930 DOI: 10.1371/journal.pntd.0010672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 08/18/2022] [Accepted: 07/18/2022] [Indexed: 11/21/2022] Open
Abstract
Buruli ulcer is a chronic skin disease caused by a toxic lipid mycolactone produced by Mycobacterium ulcerans, which induces local skin tissue destruction and analgesia. However, the cytotoxicity pathway induced by mycolactone remains largely unknown. Here we investigated the mycolactone-induced cell death pathway by screening host factors using a genome-scale lenti-CRISPR mutagenesis assay in human premonocytic THP-1 cells. As a result, 884 genes were identified as candidates causing mycolactone-induced cell death, among which SEC61A1, the α-subunit of the Sec61 translocon complex, was the highest scoring. CRISPR/Cas9 genome editing of SEC61A1 in THP-1 cells suppressed mycolactone-induced endoplasmic reticulum stress, especially eIF2α phosphorylation, and caspase-dependent apoptosis. Although previous studies have reported that mycolactone targets SEC61A1 based on mutation screening and structural analysis in several cell lines, we have reconfirmed that SEC61A1 is a mycolactone target by genome-wide screening in THP-1 cells. These results shed light on the cytotoxicity of mycolactone and suggest that the inhibition of mycolactone activity or SEC61A1 downstream cascades will be a novel therapeutic modality to eliminate the harmful effects of mycolactone in addition to the 8-week antibiotic regimen of rifampicin and clarithromycin. Buruli ulcer is a chronic skin disease caused by the bacterium Mycobacterium ulcerans. The disease mainly affects children in West Africa, and the skin ulcers are induced by mycolactone, a toxin produced by the bacteria. The mycolactone diffuses through the skin, killing cells, creating irreversible ulceration, and weakening host immune defenses. However, the cytotoxic pathway induced by mycolactone remains largely unknown. We evaluated the mycolactone-induced cell death pathway by screening host factors using a genome-scale knockout assay in human premonocytic THP-1 cells. We identified 884 genes that are potentially involved in mycolactone-induced cell death, of which SEC61A1, the α-subunit of the Sec61 translocon complex, was the highest ranking. Knockout of SEC61A1 in THP-1 cells resulted in suppression of endoplasmic reticulum stress and caspase-dependent apoptosis induced by mycolactone. These results suggest that SEC61A1 is an essential mediator of mycolactone-induced cell death.
Collapse
Affiliation(s)
- Akira Kawashima
- Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Tokyo, Japan
| | - Mitsuo Kiriya
- Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Tokyo, Japan
| | - Junichiro En
- Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Tokyo, Japan
- Department of Occupational Therapy, School of Health Science, International University of Health and Welfare, Narita, Japan
| | - Kazunari Tanigawa
- Department of Molecular Pharmaceutics, Faculty of Pharma-Science, Teikyo University, Tokyo, Japan
| | - Yasuhiro Nakamura
- Center for Promotion of Pharmaceutical Education & Research, Faculty of Pharma-Science, Teikyo University, Tokyo, Japan
| | - Yoko Fujiwara
- Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Tokyo, Japan
| | - Yuqian Luo
- Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Tokyo, Japan
- Department of Laboratory Medicine, Nanjing Drum Tower Hospital and Jiangsu Key Laboratory for Molecular Medicine, Nanjing University Medical School, Nanjing, China
| | - Keiji Maruyama
- Center for Promotion of Pharmaceutical Education & Research, Faculty of Pharma-Science, Teikyo University, Tokyo, Japan
| | - Shigekazu Watanabe
- Center for Promotion of Pharmaceutical Education & Research, Faculty of Pharma-Science, Teikyo University, Tokyo, Japan
| | - Masamichi Goto
- Department of Pathology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Koichi Suzuki
- Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Tokyo, Japan
- * E-mail:
| |
Collapse
|
4
|
Density Functional Theory-Based Studies Predict Carbon Nanotubes as Effective Mycolactone Inhibitors. Molecules 2022; 27:molecules27144440. [PMID: 35889312 PMCID: PMC9316911 DOI: 10.3390/molecules27144440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 04/19/2022] [Accepted: 05/03/2022] [Indexed: 02/04/2023] Open
Abstract
Fullerenes, boron nitride nanotubes (BNNTs), and carbon nanotubes (CNTs) have all been extensively explored for biomedical purposes. This work describes the use of BNNTs and CNTs as mycolactone inhibitors. Density functional theory (DFT) has been used to investigate the chemical properties and interaction mechanisms of mycolactone with armchair BNNTs (5,5) and armchair CNTs (5,5). By examining the optimized structure and interaction energy, the intermolecular interactions between mycolactone and nanotubes were investigated. The findings indicate that mycolactone can be physically adsorbed on armchair CNTs in a stable condition, implying that armchair CNTs can be potential inhibitors of mycolactone. According to DOS plots and HOMO–LUMO orbital studies, the electronic characteristics of pure CNTs are not modified following mycolactone adsorption on the nanotubes. Because of mycolactone’s large π-π interactions with CNTs, the estimated interaction energies indicate that mycolactone adsorption on CNTs is preferable to that on BNNTs. CNTs can be explored as potentially excellent inhibitors of mycolactone toxins in biological systems.
Collapse
|
5
|
Mycolactone enhances the Ca2+ leak from endoplasmic reticulum by trapping Sec61 translocons in a Ca2+ permeable state. Biochem J 2021; 478:4005-4024. [PMID: 34726690 PMCID: PMC8650850 DOI: 10.1042/bcj20210345] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 10/19/2021] [Accepted: 11/02/2021] [Indexed: 01/17/2023]
Abstract
The Mycobacterium ulcerans exotoxin, mycolactone, is an inhibitor of co-translational translocation via the Sec61 complex. Mycolactone has previously been shown to bind to, and alter the structure of the major translocon subunit Sec61α, and change its interaction with ribosome nascent chain complexes. In addition to its function in protein translocation into the ER, Sec61 also plays a key role in cellular Ca2+ homeostasis, acting as a leak channel between the endoplasmic reticulum (ER) and cytosol. Here, we have analysed the effect of mycolactone on cytosolic and ER Ca2+ levels using compartment-specific sensors. We also used molecular docking analysis to explore potential interaction sites for mycolactone on translocons in various states. These results show that mycolactone enhances the leak of Ca2+ ions via the Sec61 translocon, resulting in a slow but substantial depletion of ER Ca2+. This leak was dependent on mycolactone binding to Sec61α because resistance mutations in this protein completely ablated the increase. Molecular docking supports the existence of a mycolactone-binding transient inhibited state preceding translocation and suggests mycolactone may also bind Sec61α in its idle state. We propose that delayed ribosomal release after translation termination and/or translocon ‘breathing' during rapid transitions between the idle and intermediate-inhibited states allow for transient Ca2+ leak, and mycolactone's stabilisation of the latter underpins the phenotype observed.
Collapse
|
6
|
Warryn L, Dangy JP, Gersbach P, Gehringer M, Altmann KH, Pluschke G. An Antigen Capture Assay for the Detection of Mycolactone, the Polyketide Toxin of Mycobacterium ulcerans. THE JOURNAL OF IMMUNOLOGY 2021; 206:2753-2762. [PMID: 34031146 DOI: 10.4049/jimmunol.2001232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/29/2021] [Indexed: 11/19/2022]
Abstract
Mycolactone is a cytotoxin responsible for most of the chronic necrotizing pathology of Mycobacterium ulcerans disease (Buruli ulcer). The polyketide toxin consists of a 12-membered lactone ring with a lower O-linked polyunsaturated acyl side chain and an upper C-linked side chain. Mycolactone is unique to M. ulcerans and an immunological Ag capture assay would represent an important tool for the study of Buruli ulcer pathogenesis and for laboratory diagnosis. When testing sets of mycolactone-specific mouse mAbs, we found that Abs against the hydrophobic lower side chain only bind mycolactone immobilized on a solid support but not when present in solution. This observation supports previous findings that mycolactone forms micellar structures in aqueous solution with the hydrophobic region sequestered into the inner core of the aggregates. Although an Ag capture assay typically requires two Abs that recognize nonoverlapping epitopes, our search for matching pairs of mAbs showed that the same mAb could be used both as capture and as detecting reagent for the detection of the mycolactone aggregates. However, the combination of a core-specific and a core/upper side chain-specific mAb constituted the most sensitive ELISA with a sensitivity in the low nanogram range. The results of a pilot experiment showed that the sensitivity of the assay is sufficient to detect mycolactone in swab samples from Buruli ulcer lesions. Although the described capture ELISA can serve as a tool for research on the biology of mycolactone, the assay system will have to be adapted for use as a diagnostic tool.
Collapse
Affiliation(s)
- Louisa Warryn
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland; and
| | - Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland; and
| | - Philipp Gersbach
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zürich, Zürich, Switzerland
| | - Matthias Gehringer
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zürich, Zürich, Switzerland
| | - Karl-Heinz Altmann
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zürich, Zürich, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland; .,University of Basel, Basel, Switzerland; and
| |
Collapse
|
7
|
Demangel C. Immunity against Mycobacterium ulcerans: The subversive role of mycolactone. Immunol Rev 2021; 301:209-221. [PMID: 33607704 DOI: 10.1111/imr.12956] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/19/2021] [Accepted: 01/19/2021] [Indexed: 12/11/2022]
Abstract
Mycobacterium ulcerans causes Buruli ulcer, a neglected tropical skin disease manifesting as chronic wounds that can leave victims with major, life-long deformity and disability. Differently from other mycobacterial pathogens, M ulcerans produces mycolactone, a diffusible lipid factor with unique cytotoxic and immunomodulatory properties. Both traits result from mycolactone targeting Sec61, the entry point of the secretory pathway in eukaryotic cells. By inhibiting Sec61, mycolactone prevents the host cell's production of secreted proteins, and most of its transmembrane proteins. This molecular blockade dramatically alters the functions of immune cells, thereby the generation of protective immunity. Moreover, sustained inhibition of Sec61 triggers proteotoxic stress responses leading to apoptotic cell death, which can stimulate vigorous immune responses. The dynamics of bacterial production of mycolactone and elimination by infected hosts thus critically determine the balance between its immunostimulatory and immunosuppressive effects. Following an introduction summarizing the essential information on Buruli ulcer disease, this review focuses on the current state of knowledge regarding mycolactone's regulation and biodistribution. We then detail the consequences of mycolactone-mediated Sec61 blockade on initiation and maintenance of innate and adaptive immune responses. Finally, we discuss the key questions to address in order to improve immunity to M ulcerans, and how increased knowledge of mycolactone biology may pave the way to innovative therapeutics.
Collapse
Affiliation(s)
- Caroline Demangel
- Immunobiology of Infection Unit, INSERM U1221, Institut Pasteur, Paris, France
| |
Collapse
|
8
|
Van Der Werf TS, Barogui YT, Converse PJ, Phillips RO, Stienstra Y. Pharmacologic management of Mycobacterium ulcerans infection. Expert Rev Clin Pharmacol 2020; 13:391-401. [PMID: 32310683 DOI: 10.1080/17512433.2020.1752663] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Pharmacological treatment of Buruli ulcer (Mycobacterium ulcerans infection; BU) is highly effective, as shown in two randomized trials in Africa. AREAS COVERED We review BU drug treatment - in vitro, in vivo and clinical trials (PubMed: '(Buruli OR (Mycobacterium AND ulcerans)) AND (treatment OR therapy).' We also highlight the pathogenesis of M. ulcerans infection that is dominated by mycolactone, a secreted exotoxin, that causes skin and soft tissue necrosis, and impaired immune response and tissue repair. Healing is slow, due to the delayed wash-out of mycolactone. An array of repurposed tuberculosis and leprosy drugs appears effective in vitro and in animal models. In clinical trials and observational studies, only rifamycins (notably, rifampicin), macrolides (notably, clarithromycin), aminoglycosides (notably, streptomycin) and fluoroquinolones (notably, moxifloxacin, and ciprofloxacin) have been tested. EXPERT OPINION A combination of rifampicin and clarithromycin is highly effective but lesions still take a long time to heal. Novel drugs like telacebec have the potential to reduce treatment duration but this drug may remain unaffordable in low-resourced settings. Research should address ulcer treatment in general; essays to measure mycolactone over time hold promise to use as a readout for studies to compare drug treatment schedules for larger lesions of Buruli ulcer.
Collapse
Affiliation(s)
- Tjip S Van Der Werf
- Departments of Internal Medicine/Infectious Diseases, University Medical Centre Groningen, University of Groningen , Groningen, Netherlands.,Pulmonary Diseases & Tuberculosis, University Medical Centre Groningen, University of Groningen , Groningen, Netherlands
| | - Yves T Barogui
- Ministère De La Sante ́, Programme National Lutte Contre La Lèpre Et l'Ulcère De Buruli , Cotonou, Benin
| | - Paul J Converse
- Department of Medicine, Johns Hopkins University Center for Tuberculosis Research , Baltimore, Maryland, USA
| | - Richard O Phillips
- Kumasi, Ghana And Kwame Nkrumah University of Science and Technology, Komfo Anokye Teaching Hospital , Kumasi, Ghana
| | - Ymkje Stienstra
- Departments of Internal Medicine/Infectious Diseases, University Medical Centre Groningen, University of Groningen , Groningen, Netherlands
| |
Collapse
|
9
|
Avumegah MS, Waidyatillake NT, Michalski WP, O’Brien DP, Nelson TM, Athan E. Cell-mediated and serology-based tests for Mycobacterium ulcerans disease: A systematic review and meta-analysis. PLoS Negl Trop Dis 2020; 14:e0008172. [PMID: 32251470 PMCID: PMC7162525 DOI: 10.1371/journal.pntd.0008172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 04/16/2020] [Accepted: 02/26/2020] [Indexed: 11/24/2022] Open
Abstract
Buruli ulcer (BU) is a subcutaneous necrotic infection of the skin caused by Mycobacterium ulcerans. It is the third most common human mycobacterial disease after tuberculosis (TB) and leprosy. The available methods for detection of the bacilli in lesions are microscopic detection, isolation and cultivation of the bacterium, histopathology, and polymerase chain reaction (PCR). These methods, although approved by the World Health Organization (WHO), have infrastructural and resource challenges in medical centres and cell-mediated immunity (CMI) and/or serology-based tests have been suggested as easier and more appropriate for accurate assessment of the disease, especially in remote or underdeveloped areas. This study systematically reviewed and conducted a meta-analysis for all research aimed at developing cell-mediated immunity (CMI) and/or serology-based tests for M. ulcerans disease. Information for this review was searched through PubMed and Web of Science databases and identified up to June 2019. References from relevant articles and reports from the WHO Annual Meeting of the Global Buruli Ulcer Initiative were also used. Twelve studies beginning in 1952, that attempted to develop CMI and/or serology-based tests for the disease were identified. These studies addressed issues of specificity and sensitivity in context of antigen composition as well as study heterogeneity and bias. The two main types of antigenic preparations considered were pathogen-derived and recombinant protein preparations. There was slight difference in test performance when M. ulcerans recombinant proteins [positivity: 67.5%; 32.5%] or pathogen-derived [positivity: 76.0%; 24.0%] preparations were used as test antigens among BU patients. However, pathogen-derived preparations were better at differentiating between patients and control groups [odds ratio (OR) of 27.92, 95%CI: 5.05-154.28]. This was followed by tests with the recombinant proteins [OR = 1.23, 95%CI: 0.27-5.62]. Overall, study heterogeneity index, I2 was 92.4% (p = 0.000). It is apparent from this review that standardisation is needed in any future CMI and/or serology-based tests used for M. ulcerans disease.
Collapse
Affiliation(s)
- Michael S. Avumegah
- The University of Queensland, School of Chemistry and Molecular Bioscience, Brisbane, Australia
- Deakin University, School of Medicine, Geelong Australia
- Geelong Centre for Emerging Infectious Diseases (GCEID), Geelong, Australia
| | - Nilakshi T. Waidyatillake
- Department of Infectious Diseases, Barwon Health, Geelong, Australia
- Allergy and Lung Health Unit, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Wojtek P. Michalski
- Commonwealth Scientific and Industrial Research Organisation, Australian Animal Health Laboratory (CSIRO AAHL), Geelong, Australia
| | - Daniel P. O’Brien
- Department of Infectious Diseases, Barwon Health, Geelong, Australia
- Department of Medicine and Infectious Diseases, Royal Melbourne Hospital, The University of Melbourne, Melbourne, Australia
| | - Tiffanie M. Nelson
- Deakin University, School of Medicine, Geelong Australia
- Geelong Centre for Emerging Infectious Diseases (GCEID), Geelong, Australia
| | - Eugene Athan
- Deakin University, School of Medicine, Geelong Australia
- Geelong Centre for Emerging Infectious Diseases (GCEID), Geelong, Australia
- Department of Infectious Diseases, Barwon Health, Geelong, Australia
| |
Collapse
|
10
|
Reynaert ML, Dupoiron D, Yeramian E, Marsollier L, Brodin P. Could Mycolactone Inspire New Potent Analgesics? Perspectives and Pitfalls. Toxins (Basel) 2019; 11:toxins11090516. [PMID: 31487908 PMCID: PMC6783859 DOI: 10.3390/toxins11090516] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 08/26/2019] [Accepted: 09/03/2019] [Indexed: 12/20/2022] Open
Abstract
Pain currently represents the most common symptom for which medical attention is sought by patients. The available treatments have limited effectiveness and significant side-effects. In addition, most often, the duration of analgesia is short. Today, the handling of pain remains a major challenge. One promising alternative for the discovery of novel potent analgesics is to take inspiration from Mother Nature; in this context, the detailed investigation of the intriguing analgesia implemented in Buruli ulcer, an infectious disease caused by the bacterium Mycobacterium ulcerans and characterized by painless ulcerative lesions, seems particularly promising. More precisely, in this disease, the painless skin ulcers are caused by mycolactone, a polyketide lactone exotoxin. In fact, mycolactone exerts a wide range of effects on the host, besides being responsible for analgesia, as it has been shown notably to modulate the immune response or to provoke apoptosis. Several cellular mechanisms and different targets have been proposed to account for the analgesic effect of the toxin, such as nerve degeneration, the inhibition of inflammatory mediators and the activation of angiotensin II receptor 2. In this review, we discuss the current knowledge in the field, highlighting possible controversies. We first discuss the different pain-mimicking experimental models that were used to study the effect of mycolactone. We then detail the different variants of mycolactone that were used in such models. Overall, based on the results and the discussions, we conclude that the development of mycolactone-derived molecules can represent very promising perspectives for new analgesic drugs, which could be effective for specific pain indications.
Collapse
Affiliation(s)
- Marie-Line Reynaert
- France Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR8204-CIIL-Center for Infection and Immunity of Lille, F-59000 Lille, France
| | - Denis Dupoiron
- Institut de Cancérologie de l'Ouest Paul Papin, 15 rue André Boquel-49055 Angers, France
| | - Edouard Yeramian
- Unité de Microbiologie Structurale, Institut Pasteur, CNRS, Univ. Paris, F-75015 Paris, France
| | - Laurent Marsollier
- Equipe ATIP AVENIR, CRCINA, INSERM, Univ. Nantes, Univ. Angers, 4 rue Larrey, F-49933 Angers, France.
| | - Priscille Brodin
- France Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR8204-CIIL-Center for Infection and Immunity of Lille, F-59000 Lille, France.
| |
Collapse
|
11
|
Kubicek-Sutherland JZ, Vu DM, Anderson AS, Sanchez TC, Converse PJ, Martí-Arbona R, Nuermberger EL, Swanson BI, Mukundan H. Understanding the Significance of Biochemistry in the Storage, Handling, Purification, and Sampling of Amphiphilic Mycolactone. Toxins (Basel) 2019; 11:toxins11040202. [PMID: 30987300 PMCID: PMC6520765 DOI: 10.3390/toxins11040202] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/26/2019] [Accepted: 04/01/2019] [Indexed: 12/29/2022] Open
Abstract
Mycolactone, the amphiphilic macrolide toxin secreted by Mycobacterium ulcerans, plays a significant role in the pathology and manifestations of Buruli ulcer (BU). Consequently, it follows that the toxin is a suitable target for the development of diagnostics and therapeutics for this disease. Yet, several challenges have deterred such development. For one, the lipophilic nature of the toxin makes it difficult to handle and store and contributes to variability associated with laboratory experimentation and purification yields. In this manuscript, we have attempted to incorporate our understanding of the lipophilicity of mycolactone in order to define the optimal methods for the storage, handling, and purification of this toxin. We present a systematic correlation of variability associated with measurement techniques (thin-layer chromatography (TLC), mass spectrometry (MS), and UV-Vis spectrometry), storage conditions, choice of solvents, as well as the impact of each of these on toxin function as assessed by cellular cytotoxicity. We also compared natural mycolactone extracted from bacterial culture with synthesized toxins in laboratory (solvents, buffers) and physiologically relevant (serum) matrices. Our results point to the greater stability of mycolactone in organic, as well as detergent-containing, solvents, regardless of the container material (plastic, glass, or silanized tubes). They also highlight the presence of toxin in samples that may be undetectable by any one technique, suggesting that each detection approach captures different configurations of the molecule with varying specificity and sensitivity. Most importantly, our results demonstrate for the very first time that amphiphilic mycolactone associates with host lipoproteins in serum, and that this association will likely impact our ability to study, diagnose, and treat Buruli ulcers in patients.
Collapse
Affiliation(s)
| | - Dung M Vu
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Aaron S Anderson
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Timothy C Sanchez
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Paul J Converse
- Department of Medicine, Johns Hopkins University Center for Tuberculosis Research, Baltimore, MD 21218, USA.
| | | | - Eric L Nuermberger
- Department of Medicine, Johns Hopkins University Center for Tuberculosis Research, Baltimore, MD 21218, USA.
| | - Basil I Swanson
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Harshini Mukundan
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| |
Collapse
|
12
|
Demangel C, High S. Sec61 blockade by mycolactone: A central mechanism in Buruli ulcer disease. Biol Cell 2018; 110:237-248. [PMID: 30055020 DOI: 10.1111/boc.201800030] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 07/19/2018] [Indexed: 12/14/2022]
Abstract
Infection with Mycobacterium ulcerans results in a necrotising skin disease known as a Buruli ulcer, the pathology of which is directly linked to the bacterial production of the toxin mycolactone. Recent studies have identified the protein translocation machinery of the endoplasmic reticulum (ER) membrane as the primary cellular target of mycolactone, and shown that the toxin binds to the core subunit of the Sec61 complex. Mycolactone binding strongly inhibits the capacity of the Sec61 translocon to transport newly synthesised membrane and secretory proteins into and across the ER membrane. Since the ER acts as the entry point for the mammalian secretory pathway, and hence regulates initial access to the entire endomembrane system, mycolactone-treated cells have a reduced ability to produce a range of proteins including secretory cytokines and plasma membrane receptors. The global effect of this molecular blockade of protein translocation at the ER is that the host is unable to mount an effective immune response to the underlying mycobacterial infection. Prolonged exposure to mycolactone is normally cytotoxic, since it triggers stress responses activating the transcription factor ATF4 and ultimately inducing apoptosis.
Collapse
Affiliation(s)
- Caroline Demangel
- Immunobiology of Infection Unit, Institut Pasteur, Paris, France.,INSERM, U1221, Paris, France
| | - Stephen High
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| |
Collapse
|
13
|
Nakanaga K, Ogura Y, Toyoda A, Yoshida M, Fukano H, Fujiwara N, Miyamoto Y, Nakata N, Kazumi Y, Maeda S, Ooka T, Goto M, Tanigawa K, Mitarai S, Suzuki K, Ishii N, Ato M, Hayashi T, Hoshino Y. Naturally occurring a loss of a giant plasmid from Mycobacterium ulcerans subsp. shinshuense makes it non-pathogenic. Sci Rep 2018; 8:8218. [PMID: 29844323 PMCID: PMC5974349 DOI: 10.1038/s41598-018-26425-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 04/30/2018] [Indexed: 12/30/2022] Open
Abstract
Mycobacterium ulcerans is the causative agent of Buruli ulcer (BU), a WHO-defined neglected tropical disease. All Japanese BU causative isolates have shown distinct differences from the prototype and are categorized as M. ulcerans subspecies shinshuense. During repeated sub-culture, we found that some M. shinshuense colonies were non-pigmented whereas others were pigmented. Whole genome sequence analysis revealed that non-pigmented colonies did not harbor a giant plasmid, which encodes elements needed for mycolactone toxin biosynthesis. Moreover, mycolactone was not detected in sterile filtrates of non-pigmented colonies. Mice inoculated with suspensions of pigmented colonies died within 5 weeks whereas those infected with suspensions of non-pigmented colonies had significantly prolonged survival (>8 weeks). This study suggests that mycolactone is a critical M. shinshuense virulence factor and that the lack of a mycolactone-producing giant plasmid makes the strain non-pathogenic. We made an avirulent mycolactone-deletion mutant strain directly from the virulent original.
Collapse
Affiliation(s)
- Kazue Nakanaga
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yoshitoshi Ogura
- Department of Bacteriology, Faculty of Medicine, Kyushu University, Fukuoka, Japan
| | - Atsushi Toyoda
- Center for Information Biology, National Institute of Genetics, Shizuoka, Japan
| | - Mitsunori Yoshida
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Hanako Fukano
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Nagatoshi Fujiwara
- Department of Food and Nutrition, Faculty of Contemporary Human Life Science, Tezukayama University, Nara, Japan
| | - Yuji Miyamoto
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Noboru Nakata
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yuko Kazumi
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan
- The Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Shinji Maeda
- The Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan
- School of Pharmacy, Hokkaido Pharmaceutical University, Sapporo, Japan
| | - Tadasuke Ooka
- Department of Microbiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | | | - Kazunari Tanigawa
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
- Faculty of Pharma-Sciences, Teikyo University, Tokyo, Japan
| | - Satoshi Mitarai
- The Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Koichi Suzuki
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
- Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Tokyo, Japan
| | - Norihisa Ishii
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Manabu Ato
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tetsuya Hayashi
- Department of Bacteriology, Faculty of Medicine, Kyushu University, Fukuoka, Japan
| | - Yoshihiko Hoshino
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan.
| |
Collapse
|
14
|
Saint-Auret S, Abdelkafi H, Le Nouen D, Guenin-Macé L, Demangel C, Bisseret P, Blanchard N. Modular total syntheses of mycolactone A/B and its [ 2H]-isotopologue. Org Biomol Chem 2018; 15:7518-7522. [PMID: 28871293 DOI: 10.1039/c7ob01943b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A modular total synthesis of mycolactone A/B, the exotoxin produced by Mycobacterium ulcerans, has been achieved through the orchestration of several Pd-catalyzed key steps. While this route leads to a mixture of the natural product and its C12 epimer (4 : 1 ratio), this was inconsequential from the biological activity standpoint. Compared to the previously reported routes, this synthetic blueprint allows the late-stage modification of the toxin, as exemplified by the preparation of [22,22,22-2H3]-mycolactone A/B.
Collapse
Affiliation(s)
- Sarah Saint-Auret
- Université de Strasbourg, CNRS, Laboratoire de Chimie Moléculaire UMR 7509, 67000 Strasbourg, France.
| | | | | | | | | | | | | |
Collapse
|
15
|
Membrane perturbing properties of toxin mycolactone from Mycobacterium ulcerans. PLoS Comput Biol 2018; 14:e1005972. [PMID: 29401455 PMCID: PMC5814095 DOI: 10.1371/journal.pcbi.1005972] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 02/15/2018] [Accepted: 01/15/2018] [Indexed: 12/16/2022] Open
Abstract
Mycolactone is the exotoxin produced by Mycobacterium ulcerans and is the virulence factor behind the neglected tropical disease Buruli ulcer. The toxin has a broad spectrum of biological effects within the host organism, stemming from its interaction with at least two molecular targets and the inhibition of protein uptake into the endoplasmic reticulum. Although it has been shown that the toxin can passively permeate into host cells, it is clearly lipophilic. Association with lipid carriers would have substantial implications for the toxin’s distribution within a host organism, delivery to cellular targets, diagnostic susceptibility, and mechanisms of pathogenicity. Yet the toxin’s interactions with, and distribution in, lipids are unknown. Herein we have used coarse-grained molecular dynamics simulations, guided by all-atom simulations, to study the interaction of mycolactone with pure and mixed lipid membranes. Using established techniques, we calculated the toxin’s preferential localization, membrane translocation, and impact on membrane physical and dynamical properties. The computed water-octanol partition coefficient indicates that mycolactone prefers to be in an organic phase rather than in an aqueous environment. Our results show that in a solvated membrane environment the exotoxin mainly localizes in the water-membrane interface, with a preference for the glycerol moiety of lipids, consistent with the reported studies that found it in lipid extracts of the cell. The calculated association constant to the model membrane is similar to the reported association constant for Wiskott-Aldrich syndrome protein. Mycolactone is shown to modify the physical properties of membranes, lowering the transition temperature, compressibility modulus, and critical line tension at which pores can be stabilized. It also shows a tendency to behave as a linactant, a molecule that localizes at the boundary between different fluid lipid domains in membranes and promotes inter-mixing of domains. This property has implications for the toxin’s cellular access, T-cell immunosuppression, and therapeutic potential. Mycolactone is a macrolide exotoxin secreted by Mycobacterium ulcerans, which causes a skin disease called Buruli ulcer, a neglected emerging disease. It is the third most common mycobacterial disease after tuberculosis and leprosy. Studies have shown how mycolactone plays a pivotal role in Buruli ulcer pathogenesis, and identified it as an attractive therapeutic target. This multifunctional cytotoxin exerts multiple local and global responses, including ulcerative, analgesic, and anti-inflammatory effects. Prompted by its lipid-like structure, we used extensive multi-resolution simulations to probe mycolactone’s interactions with model membranes. Our results suggest that mycolactone is sequestered in membranes where it alters several dynamical, physical, and mechanical properties. It also behaves as a linactant, localizing at the interface between lipid domains and decreasing the inter-domain line tension. Our results shed light on how mycolactone permeates host cell membranes and is distributed between lipid and aqueous environments. These findings have significant implications for the toxin’s distribution in the host environment and mechanisms of pathogenicity. Understanding the toxin’s distribution and mechanism of trafficking will have ramifications for targeted diagnostics, therapeutic approaches, and our understanding of Buruli ulcer pathogenesis.
Collapse
|
16
|
Gehringer M, Altmann KH. The chemistry and biology of mycolactones. Beilstein J Org Chem 2017; 13:1596-1660. [PMID: 28904608 PMCID: PMC5564285 DOI: 10.3762/bjoc.13.159] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 07/21/2017] [Indexed: 12/21/2022] Open
Abstract
Mycolactones are a group of macrolides excreted by the human pathogen Mycobacterium ulcerans, which exhibit cytotoxic, immunosuppressive and analgesic properties. As the virulence factor of M. ulcerans, mycolactones are central to the pathogenesis of the neglected disease Buruli ulcer, a chronic and debilitating medical condition characterized by necrotic skin ulcers. Due to their complex structure and fascinating biology, mycolactones have inspired various total synthesis endeavors and structure-activity relationship studies. Although this review intends to cover all synthesis efforts in the field, special emphasis is given to the comparison of conceptually different approaches and to the discussion of more recent contributions. Furthermore, a detailed discussion of molecular targets and structure-activity relationships is provided.
Collapse
Affiliation(s)
- Matthias Gehringer
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
| | - Karl-Heinz Altmann
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland
| |
Collapse
|
17
|
En J, Kitamoto S, Kawashima A, Yonezawa S, Kishi Y, Ishii N, Goto M. Mycolactone cytotoxicity in Schwann cells could explain nerve damage in Buruli ulcer. PLoS Negl Trop Dis 2017; 11:e0005834. [PMID: 28783752 PMCID: PMC5559071 DOI: 10.1371/journal.pntd.0005834] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 08/16/2017] [Accepted: 07/25/2017] [Indexed: 01/11/2023] Open
Abstract
Buruli ulcer is a chronic painless skin disease caused by Mycobacterium ulcerans. The local nerve damage induced by M. ulcerans invasion is similar to the nerve damage evoked by the injection of mycolactone in a Buruli ulcer mouse model. In order to elucidate the mechanism of this nerve damage, we tested and compared the cytotoxic effect of synthetic mycolactone A/B on cultured Schwann cells, fibroblasts and macrophages. Mycolactone induced much higher cell death and apoptosis in Schwann cell line SW10 than in fibroblast line L929. These results suggest that mycolactone is a key substance in the production of nerve damage of Buruli ulcer. Buruli ulcer is a chronic skin disease caused by Mycobacterium ulcerans, and the disease is characterized by the painless nature of its lesion. Similar to leprosy, loss of pain often hinders the patients from taking proper medical care, resulting in gross deformities. A toxic lipid mycolactone produced from Mycobacterium ulcerans was thought to block the sensory system of the lesion, either by direct cellular damage (cytotoxicity) to the regional nerve tissue, or by a more sophisticated, non-toxic paralyzing mechanism. In the peripheral nerve, Schwann cells nourish axons and accelerate nerve conduction. In this study, we have compared the cytotoxic potential of mycolactone on cultured Schwann cells and that on fibroblasts, and found that mycolactone A/B induced much higher cell death and apoptosis in Schwann cell line SW10 than in fibroblast line L929. These results support the cytotoxic theory and suggest that mycolactone is a key substance in the production of nerve damage of Buruli ulcer.
Collapse
Affiliation(s)
- Junichiro En
- Department of Pathology, Kagoshima University, Kagoshima, Japan
- National Sanatorium Hoshizuka-Keiaien, Kanoya, Kagoshima, Japan
- International University of Health and Welfare, Narita, Chiba, Japan
- * E-mail:
| | - Sho Kitamoto
- Department of Pathology, Kagoshima University, Kagoshima, Japan
- Division of Gastroenterology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Akira Kawashima
- Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Itabashi, Tokyo, Japan
| | - Suguru Yonezawa
- Department of Pathology, Kagoshima University, Kagoshima, Japan
| | - Yoshito Kishi
- Department of Chemistry and Chemical Biology, Harvard University, Boston, Massachusetts, United States of America
| | - Norihisa Ishii
- Leprosy Research Center, National Institute of Infectious Diseases, Higashimurayama, Tokyo, Japan
| | - Masamichi Goto
- Department of Pathology, Kagoshima University, Kagoshima, Japan
- National Sanatorium Hoshizuka-Keiaien, Kanoya, Kagoshima, Japan
| |
Collapse
|
18
|
Babu VS, Zhou Y, Kishi Y. Design, synthesis, and cytotoxicity of stabilized mycolactone analogs. Bioorg Med Chem Lett 2017; 27:1274-1277. [PMID: 28159417 DOI: 10.1016/j.bmcl.2017.01.036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 01/11/2017] [Accepted: 01/12/2017] [Indexed: 11/16/2022]
Abstract
On exposure to visible light, mycolactone A/B, the causative toxin of Buruli ulcer, rearranges to a mixture of four photo-mycolactones apparently via a rare photochemically-induced [4πs+2πa] cycloaddition. In order to prevent the rearrangement, two C6'-C7' dihydromycolactone analogs 6'α-15 and 6'β-15 were designed and synthesized. 6'α-15 and 6'β-15 were shown to be stable under not only photochemical, but also acidic and basic conditions. Cytotoxicity was tested against arbitrarily chosen four cell lines (human Hek-293, human lung carcinoma A-549, human melanoma LOX-IMVI, and mouse L-929), thereby revealing that: (1) both analogs maintain potent cytotoxicity; (2) 6'β-15 exhibits significantly higher potency against human cell lines than 6'α-15; (3) in comparison with parent mycolactone A/B, 6'β-15 exhibits equal potency against human Hek-293, whereas significantly lower potency against human lung carcinoma A-549 and human melanoma LOX-IMVI.
Collapse
Affiliation(s)
- Vaddela Sudheer Babu
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA
| | - Ya Zhou
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA
| | - Yoshito Kishi
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA.
| |
Collapse
|
19
|
Garg N, Luzzatto-Knaan T, Melnik AV, Caraballo-Rodríguez AM, Floros DJ, Petras D, Gregor R, Dorrestein PC, Phelan VV. Natural products as mediators of disease. Nat Prod Rep 2017; 34:194-219. [PMID: 27874907 PMCID: PMC5299058 DOI: 10.1039/c6np00063k] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Covering: up to 2016Humans are walking microbial ecosystems, each harboring a complex microbiome with the genetic potential to produce a vast array of natural products. Recent sequencing data suggest that our microbial inhabitants are critical for maintaining overall health. Shifts in microbial communities have been correlated to a number of diseases including infections, inflammation, cancer, and neurological disorders. Some of these clinically and diagnostically relevant phenotypes are a result of the presence of small molecules, yet we know remarkably little about their contributions to the health of individuals. Here, we review microbe-derived natural products as mediators of human disease.
Collapse
Affiliation(s)
- Neha Garg
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Tal Luzzatto-Knaan
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Alexey V. Melnik
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | | | - Dimitrios J. Floros
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093
| | - Daniel Petras
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Rachel Gregor
- Department of Chemistry and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Be’er Sheva 84105, Israel
| | - Pieter C. Dorrestein
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Vanessa V. Phelan
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045
| |
Collapse
|
20
|
Saint-Auret S, Abdelkafi H, Le Nouen D, Bisseret P, Blanchard N. Synthetic strategies towards mycolactone A/B, an exotoxin secreted by Mycobacterium ulcerans. Org Chem Front 2017. [DOI: 10.1039/c7qo00608j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Pitfalls and dead-ends pave the way to mycolactone A/B. This full account reports synthetic efforts towards this natural product that eventually culminated in a de novo total synthesis.
Collapse
Affiliation(s)
- Sarah Saint-Auret
- Université de Strasbourg
- CNRS
- Laboratoire de Chimie Moléculaire UMR 7509
- 67000 Strasbourg
- France
| | - Hajer Abdelkafi
- Université de Strasbourg
- CNRS
- Laboratoire de Chimie Moléculaire UMR 7509
- 67000 Strasbourg
- France
| | - Didier Le Nouen
- Université de Haute-Alsace
- Laboratoire de Chimie Organique et Bioorganique EA 4566
- 68093 Mulhouse Cedex
- France
| | - Philippe Bisseret
- Université de Strasbourg
- CNRS
- Laboratoire de Chimie Moléculaire UMR 7509
- 67000 Strasbourg
- France
| | - Nicolas Blanchard
- Université de Strasbourg
- CNRS
- Laboratoire de Chimie Moléculaire UMR 7509
- 67000 Strasbourg
- France
| |
Collapse
|
21
|
Mousa WK, Athar B, Merwin NJ, Magarvey NA. Antibiotics and specialized metabolites from the human microbiota. Nat Prod Rep 2017; 34:1302-1331. [DOI: 10.1039/c7np00021a] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Human microbiota associated with each body site produce specialized molecules to kill human pathogens. Advanced bioinformatics tools will help to discover unique microbiome chemistry.
Collapse
Affiliation(s)
- Walaa K. Mousa
- Departments of Biochemistry and Biomedical Sciences & Chemistry and Chemical Biology
- M. G. DeGroote Institute for Infectious Disease Research
- McMaster University
- Hamilton
- Canada L8S 4K1
| | - Bilal Athar
- Departments of Biochemistry and Biomedical Sciences & Chemistry and Chemical Biology
- M. G. DeGroote Institute for Infectious Disease Research
- McMaster University
- Hamilton
- Canada L8S 4K1
| | - Nishanth J. Merwin
- Departments of Biochemistry and Biomedical Sciences & Chemistry and Chemical Biology
- M. G. DeGroote Institute for Infectious Disease Research
- McMaster University
- Hamilton
- Canada L8S 4K1
| | - Nathan A. Magarvey
- Departments of Biochemistry and Biomedical Sciences & Chemistry and Chemical Biology
- M. G. DeGroote Institute for Infectious Disease Research
- McMaster University
- Hamilton
- Canada L8S 4K1
| |
Collapse
|
22
|
Anyim MC, Meka AO, Chukwu JN, Nwafor CC, Oshi DC, Madichie NO, Ekeke N, Alphonsus C, Mbah O, Nwaekpe C, Njoku M, Fakiyesi D, Ulodiaku V, Ejiofor I, Bisiriyu AH, Ukwaja KN. Secondary bacterial isolates from previously untreated Buruli ulcer lesions and their antibiotic susceptibility patterns in Southern Nigeria. Rev Soc Bras Med Trop 2016; 49:746-751. [PMID: 28001222 DOI: 10.1590/0037-8682-0404-2016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Accepted: 11/22/2016] [Indexed: 11/21/2022] Open
Affiliation(s)
| | | | | | | | | | | | - Ngozi Ekeke
- German Leprosy and Tuberculosis Relief Association, Nigeria
| | | | - Obinna Mbah
- German Leprosy and Tuberculosis Relief Association, Nigeria
| | | | - Martin Njoku
- St Benedict's Tuberculosis & Leprosy Rehabilitation Hospital, Nigeria
| | - Dare Fakiyesi
- St Benedict's Tuberculosis & Leprosy Rehabilitation Hospital, Nigeria
| | | | | | | | | |
Collapse
|
23
|
Gomes C, Martínez-Puchol S, Palma N, Horna G, Ruiz-Roldán L, Pons MJ, Ruiz J. Macrolide resistance mechanisms in Enterobacteriaceae: Focus on azithromycin. Crit Rev Microbiol 2016; 43:1-30. [DOI: 10.3109/1040841x.2015.1136261] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Cláudia Gomes
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic ? Universitat de Barcelona, Spain
| | - Sandra Martínez-Puchol
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic ? Universitat de Barcelona, Spain
| | - Noemí Palma
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic ? Universitat de Barcelona, Spain
| | - Gertrudis Horna
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic ? Universitat de Barcelona, Spain
- Universidad Peruana Cayetano Heredia, Lima, Peru
| | | | - Maria J Pons
- Universidad Peruana de Ciencias Aplicadas, Lima, Peru
| | - Joaquim Ruiz
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic ? Universitat de Barcelona, Spain
| |
Collapse
|
24
|
Dangy JP, Scherr N, Gersbach P, Hug MN, Bieri R, Bomio C, Li J, Huber S, Altmann KH, Pluschke G. Antibody-Mediated Neutralization of the Exotoxin Mycolactone, the Main Virulence Factor Produced by Mycobacterium ulcerans. PLoS Negl Trop Dis 2016; 10:e0004808. [PMID: 27351976 PMCID: PMC4924874 DOI: 10.1371/journal.pntd.0004808] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 06/06/2016] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Mycolactone, the macrolide exotoxin produced by Mycobacterium ulcerans, causes extensive tissue destruction by inducing apoptosis of host cells. In this study, we aimed at the production of antibodies that could neutralize the cytotoxic activities of mycolactone. METHODOLOGY/PRINCIPAL FINDINGS Using the B cell hybridoma technology, we generated a series of monoclonal antibodies with specificity for mycolactone from spleen cells of mice immunized with the protein conjugate of a truncated synthetic mycolactone derivative. L929 fibroblasts were used as a model system to investigate whether these antibodies can inhibit the biological effects of mycolactone. By measuring the metabolic activity of the fibroblasts, we found that anti-mycolactone mAbs can completely neutralize the cytotoxic activity of mycolactone. CONCLUSIONS/SIGNIFICANCE The toxin neutralizing capacity of anti-mycolactone mAbs supports the concept of evaluating the macrolide toxin as vaccine target.
Collapse
Affiliation(s)
- Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Nicole Scherr
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Philipp Gersbach
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology (ETH) Zürich, Zürich, Switzerland
| | - Melanie N. Hug
- Roche Innovation Center, Chemical Biology, Basel, Switzerland
| | - Raphael Bieri
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Claudio Bomio
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology (ETH) Zürich, Zürich, Switzerland
| | - Jun Li
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology (ETH) Zürich, Zürich, Switzerland
| | - Sylwia Huber
- Roche Innovation Center, Chemical Biology, Basel, Switzerland
| | - Karl-Heinz Altmann
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology (ETH) Zürich, Zürich, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
| |
Collapse
|
25
|
Anand U, Sinisi M, Fox M, MacQuillan A, Quick T, Korchev Y, Bountra C, McCarthy T, Anand P. Mycolactone-mediated neurite degeneration and functional effects in cultured human and rat DRG neurons: Mechanisms underlying hypoalgesia in Buruli ulcer. Mol Pain 2016; 12:12/0/1744806916654144. [PMID: 27325560 PMCID: PMC4956182 DOI: 10.1177/1744806916654144] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 05/16/2016] [Indexed: 01/08/2023] Open
Abstract
Background Mycolactone is a polyketide toxin secreted by the mycobacterium Mycobacterium ulcerans, responsible for the extensive hypoalgesic skin lesions characteristic of patients with Buruli ulcer. A recent pre-clinical study proposed that mycolactone may produce analgesia via activation of the angiotensin II type 2 receptor (AT2R). In contrast, AT2R antagonist EMA401 has shown analgesic efficacy in animal models and clinical trials for neuropathic pain. We therefore investigated the morphological and functional effects of mycolactone in cultured human and rat dorsal root ganglia (DRG) neurons and the role of AT2R using EMA401. Primary sensory neurons were prepared from avulsed cervical human DRG and rat DRG; 24 h after plating, neurons were incubated for 24 to 96 h with synthetic mycolactone A/B, followed by immunostaining with antibodies to PGP9.5, Gap43, β tubulin, or Mitotracker dye staining. Acute functional effects were examined by measuring capsaicin responses with calcium imaging in DRG neuronal cultures treated with mycolactone. Results Morphological effects: Mycolactone-treated cultures showed dramatically reduced numbers of surviving neurons and non-neuronal cells, reduced Gap43 and β tubulin expression, degenerating neurites and reduced cell body diameter, compared with controls. Dose-related reduction of neurite length was observed in mycolactone-treated cultures. Mitochondria were distributed throughout the length of neurites and soma of control neurons, but clustered in the neurites and soma of mycolactone-treated neurons. Functional effects: Mycolactone-treated human and rat DRG neurons showed dose-related inhibition of capsaicin responses, which were reversed by calcineurin inhibitor cyclosporine and phosphodiesterase inhibitor 3-isobutyl-1-Methylxanthine, indicating involvement of cAMP/ATP reduction. The morphological and functional effects of mycolactone were not altered by Angiotensin II or AT2R antagonist EMA401. Conclusion Mycolactone induces toxic effects in DRG neurons, leading to impaired nociceptor function, neurite degeneration, and cell death, resembling the cutaneous hypoalgesia and nerve damage in individuals with M. Ulcerans infection.
Collapse
Affiliation(s)
- U Anand
- Department of Medicine, Imperial College London, Hammersmith Hospital, London, UK
| | - M Sinisi
- Peripheral Nerve Injury Unit, Royal National Orthopaedic Hospital, Middlesex, UK
| | - M Fox
- Peripheral Nerve Injury Unit, Royal National Orthopaedic Hospital, Middlesex, UK
| | - A MacQuillan
- Peripheral Nerve Injury Unit, Royal National Orthopaedic Hospital, Middlesex, UK
| | - T Quick
- Peripheral Nerve Injury Unit, Royal National Orthopaedic Hospital, Middlesex, UK
| | - Y Korchev
- Department of Medicine, Imperial College London, Hammersmith Hospital, London, UK
| | - C Bountra
- University of Oxford Structural Genomics Consortium, Headington, Oxford, UK
| | - T McCarthy
- Spinifex Pharmaceuticals Pty Ltd, St. Preston, VIC, Australia
| | - P Anand
- Department of Medicine, Imperial College London, Hammersmith Hospital, London, UK
| |
Collapse
|
26
|
Barogui YT, Klis SA, Johnson RC, Phillips RO, van der Veer E, van Diemen C, van der Werf TS, Stienstra Y. Genetic Susceptibility and Predictors of Paradoxical Reactions in Buruli Ulcer. PLoS Negl Trop Dis 2016; 10:e0004594. [PMID: 27097163 PMCID: PMC4838240 DOI: 10.1371/journal.pntd.0004594] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Accepted: 03/09/2016] [Indexed: 01/23/2023] Open
Abstract
Introduction Buruli ulcer (BU) is the third most frequent mycobacterial disease in immunocompetent persons after tuberculosis and leprosy. During the last decade, eight weeks of antimicrobial treatment has become the standard of care. This treatment may be accompanied by transient clinical deterioration, known as paradoxical reaction. We investigate the incidence and the risks factors associated with paradoxical reaction in BU. Methods The lesion size of participants was assessed by careful palpation and recorded by serial acetate sheet tracings. For every time point, surface area was compared with the previous assessment. All patients received antimicrobial treatment for 8 weeks. Serum concentration of 25-hydroxyvitamin D, the primary indicator of vitamin D status, was determined in duplex for blood samples at baseline by a radioimmunoassay. We genotyped four polymorphisms in the SLC11A1 gene, previously associated with susceptibility to BU. For testing the association of genetic variants with paradoxical responses, we used a binary logistic regression analysis with the occurrence of a paradoxical response as the dependent variable. Results Paradoxical reaction occurred in 22% of the patients; the reaction was significantly associated with trunk localization (p = .039 by Χ2), larger lesions (p = .021 by Χ2) and genetic factors. The polymorphisms 3’UTR TGTG ins/ins (OR 7.19, p < .001) had a higher risk for developing paradoxical reaction compared to ins/del or del/del polymorphisms. Conclusions Paradoxical reactions are common in BU. They are associated with trunk localization, larger lesions and polymorphisms in the SLC11A1 gene. Buruli ulcer is an infectious disease of skin, subcutaneous fat and sometimes bone, mainly affecting children in West Africa. It is considered as one of the Neglected Tropical Diseases but the disease occurs also in moderate climates like South East Australia and Japan where it may also affect adults. Once a patient has started antibiotic treatment, lesions may increase in size even if the antimicrobial treatment is effective; this is highly confusing for doctors and patients as they may think that treatment actually fails. The cause of Buruli ulcer is Mycobacterium ulcerans, related to other mycobacteria that cause disease in man, like leprosy and tuberculosis. Using data from two different studies in West Africa, we show that these paradoxical reactions are associated with trunk localization and that they occur more often in larger lesions. The chance to develop these reactions appeared partly inherited: carrying the homozygous ins/ins genotype of 3’UTR TGTG 285 polymorphism in the SLC11A1 gene increased the risk of paradoxical reactions. Vitamin D is important for the immune defense against infections by mycobacteria. Vitamin D blood concentrations were not associated with paradoxical reactions; patients generally did well, and we did not need corticosteroid immune suppression to overcome these reactions.
Collapse
Affiliation(s)
- Yves Thierry Barogui
- Centre de Dépistage et de Traitement de l’Ulcère de Buruli de Lalo, Ministère de la Santé, Cotonou, Bénin
- Department of Internal Medicine, Infectious Diseases Service, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Sandor-Adrian Klis
- Department of Internal Medicine, Infectious Diseases Service, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Roch Christian Johnson
- Centre Interfacultaire de Formation et de Recherche en Environnement pour le Développement Durable, Université d’Abomey-Calavi, Abomey-Calavi, Bénin
| | | | - Eveline van der Veer
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Cleo van Diemen
- Department of Genetics, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Tjip S. van der Werf
- Department of Internal Medicine, Infectious Diseases Service, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
- Department of Pulmonary Diseases & Tuberculosis, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
- * E-mail:
| | - Ymkje Stienstra
- Department of Internal Medicine, Infectious Diseases Service, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| |
Collapse
|
27
|
Guenin-Macé L, Baron L, Chany AC, Tresse C, Saint-Auret S, Jönsson F, Le Chevalier F, Bruhns P, Bismuth G, Hidalgo-Lucas S, Bisson JF, Blanchard N, Demangel C. Shaping mycolactone for therapeutic use against inflammatory disorders. Sci Transl Med 2016; 7:289ra85. [PMID: 26019221 DOI: 10.1126/scitranslmed.aab0458] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Inflammation adversely affects the health of millions of people worldwide, and there is an unmet medical need for better anti-inflammatory drugs. We evaluated the therapeutic interest of mycolactone, a polyketide-derived macrolide produced by Mycobacterium ulcerans. Bacterial production of mycolactone in human skin causes a combination of ulcerative, analgesic, and anti-inflammatory effects. Whereas ulcer formation is mediated by the proapoptotic activity of mycolactone on skin cells via hyperactivation of Wiskott-Aldrich syndrome proteins, analgesia results from neuronal hyperpolarization via signaling through angiotensin II type 2 receptors. Mycolactone also blunts the capacity of immune cells to produce inflammatory mediators by an independent mechanism of protein synthesis blockade. In an attempt to isolate the structural determinants of mycolactone's immunosuppressive activity, we screened a library of synthetic subunits of mycolactone for inhibition of cytokine production by activated T cells. The minimal structure retaining immunosuppressive activity was a truncated version of mycolactone, missing one of the two core-branched polyketide chains. This compound inhibited the inflammatory cytokine responses of human primary cells at noncytotoxic doses and bound to angiotensin II type 2 receptors comparably to mycolactone in vitro. Notably, it was considerably less toxic than mycolactone in human primary dermal fibroblasts modeling ulcerative activity. In mouse models of human diseases, it conferred systemic protection against chronic skin inflammation and inflammatory pain, with no apparent side effects. In addition to establishing the anti-inflammatory potency of mycolactone in vivo, our study therefore highlights the translational potential of mycolactone core-derived structures as prospective immunosuppressants.
Collapse
Affiliation(s)
- Laure Guenin-Macé
- Institut Pasteur, Unité d'Immunobiologie de l'Infection, Paris 75015, France. CNRS URA 1961, Paris 75015, France
| | - Ludivine Baron
- Institut Pasteur, Unité d'Immunobiologie de l'Infection, Paris 75015, France. CNRS URA 1961, Paris 75015, France
| | - Anne-Caroline Chany
- Université de Strasbourg, Laboratoire de Chimie Moléculaire, ECPM-CNRS UMR 7509, Strasbourg 67087, France
| | - Cédric Tresse
- Université de Strasbourg, Laboratoire de Chimie Moléculaire, ECPM-CNRS UMR 7509, Strasbourg 67087, France
| | - Sarah Saint-Auret
- Université de Strasbourg, Laboratoire de Chimie Moléculaire, ECPM-CNRS UMR 7509, Strasbourg 67087, France
| | - Friederike Jönsson
- Institut Pasteur, Unité Anticorps en Thérapie et Pathologie, Paris 75015, France. INSERM U760, Paris 75015, France
| | - Fabien Le Chevalier
- Institut Pasteur, Unité d'Immunobiologie de l'Infection, Paris 75015, France
| | - Pierre Bruhns
- Institut Pasteur, Unité Anticorps en Thérapie et Pathologie, Paris 75015, France. INSERM U760, Paris 75015, France
| | - Georges Bismuth
- INSERM U1016, Institut Cochin, Paris 75014, France. Université Paris Descartes, Paris 75014, France. CNRS UMR 8104, Paris 75014, France
| | - Sophie Hidalgo-Lucas
- ETAP, Inflammation, Dermatologie et Toxicologie, Vandœuvre-lès-Nancy 54500, France
| | - Jean-François Bisson
- ETAP, Inflammation, Dermatologie et Toxicologie, Vandœuvre-lès-Nancy 54500, France
| | - Nicolas Blanchard
- Université de Strasbourg, Laboratoire de Chimie Moléculaire, ECPM-CNRS UMR 7509, Strasbourg 67087, France
| | - Caroline Demangel
- Institut Pasteur, Unité d'Immunobiologie de l'Infection, Paris 75015, France. CNRS URA 1961, Paris 75015, France.
| |
Collapse
|
28
|
Brown CA, Aggarwal VK. Short Convergent Synthesis of the Mycolactone Core Through Lithiation-Borylation Homologations. Chemistry 2015; 21:13900-3. [PMID: 26332797 PMCID: PMC6519258 DOI: 10.1002/chem.201503122] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Indexed: 12/17/2022]
Abstract
Using iterative lithiation-borylation homologations, the mycolactone toxin core has been synthesized in 13 steps and 17% overall yield. The rapid build-up of molecular complexity, high convergence and high stereoselectivity are noteworthy features of this synthesis.
Collapse
Affiliation(s)
- Christopher A Brown
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS (UK)
| | - Varinder K Aggarwal
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS (UK).
| |
Collapse
|
29
|
Abstract
Developments in the use of genomics to guide natural product discovery and a recent emphasis on understanding the molecular mechanisms of microbiota-host interactions have converged on the discovery of small molecules from the human microbiome. Here, we review what is known about small molecules produced by the human microbiota. Numerous molecules representing each of the major metabolite classes have been found that have a variety of biological activities, including immune modulation and antibiosis. We discuss technologies that will affect how microbiota-derived molecules are discovered in the future and consider the challenges inherent in finding specific molecules that are critical for driving microbe-host and microbe-microbe interactions and understanding their biological relevance.
Collapse
Affiliation(s)
- Mohamed S Donia
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
| | - Michael A Fischbach
- Department of Bioengineering and Therapeutic Sciences and the California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, CA 94158, USA.
| |
Collapse
|
30
|
Li X, Babu VS, Kishi Y. Stereoselective total synthesis and stereochemistry confirmation of photo-mycolactones. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2014.12.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
31
|
Li K, Chung-Davidson YW, Bussy U, Li W. Recent advances and applications of experimental technologies in marine natural product research. Mar Drugs 2015; 13:2694-713. [PMID: 25939037 PMCID: PMC4446601 DOI: 10.3390/md13052694] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 04/02/2015] [Accepted: 04/14/2015] [Indexed: 11/16/2022] Open
Abstract
Marine natural products are a rich source of novel and biologically active compounds. The number of identified marine natural compounds has grown 20% over the last five years from 2009 to 2013. Several challenges, including sample collection and structure elucidation, have limited the development of this research field. Nonetheless, new approaches, such as sampling strategies for organisms from extreme ocean environments, nanoscale NMR and computational chemistry for structural determination, are now available to overcome the barriers. In this review, we highlight the experimental technology innovations in the field of marine natural products, which in our view will lead to the development of many new drugs in the future.
Collapse
Affiliation(s)
- Ke Li
- Department of Fisheries and Wildlife, Michigan State University, Room 13 Natural Resources Building, 480 Wilson Road, East Lansing, MI 48824, USA.
| | - Yu-Wen Chung-Davidson
- Department of Fisheries and Wildlife, Michigan State University, Room 13 Natural Resources Building, 480 Wilson Road, East Lansing, MI 48824, USA.
| | - Ugo Bussy
- Department of Fisheries and Wildlife, Michigan State University, Room 13 Natural Resources Building, 480 Wilson Road, East Lansing, MI 48824, USA.
| | - Weiming Li
- Department of Fisheries and Wildlife, Michigan State University, Room 13 Natural Resources Building, 480 Wilson Road, East Lansing, MI 48824, USA.
| |
Collapse
|
32
|
Pleiotropic molecular effects of the Mycobacterium ulcerans virulence factor mycolactone underlying the cell death and immunosuppression seen in Buruli ulcer. Biochem Soc Trans 2014; 42:177-83. [PMID: 24450648 DOI: 10.1042/bst20130133] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Mycolactone is a polyketide macrolide lipid-like secondary metabolite synthesized by Mycobacterium ulcerans, the causative agent of BU (Buruli ulcer), and is the only virulence factor for this pathogen identified to date. Prolonged exposure to high concentrations of mycolactone is cytotoxic to diverse mammalian cells (albeit with varying efficiency), whereas at lower doses it has a spectrum of immunosuppressive activities. Combined, these pleiotropic properties have a powerful influence on local and systemic cellular function that should explain the pathophysiology of BU disease. The last decade has seen significant advances in our understanding of the molecular mechanisms underlying these effects in a range of different cell types. The present review focuses on the current state of our knowledge of mycolactone function, and its molecular and cellular targets, and seeks to identify commonalities between the different functional and cellular systems. Since mycolactone influences fundamental cellular processes (cell division, cell death and inflammation), getting to the root of how mycolactone achieves this could have a profound impact on our understanding of eukaryotic cell biology.
Collapse
|
33
|
Chany AC, Veyron-Churlet R, Tresse C, Mayau V, Casarotto V, Le Chevalier F, Guenin-Macé L, Demangel C, Blanchard N. Synthetic variants of mycolactone bind and activate Wiskott-Aldrich syndrome proteins. J Med Chem 2014; 57:7382-95. [PMID: 25158122 DOI: 10.1021/jm5008819] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Mycolactone is a complex macrolide toxin produced by Mycobacterium ulcerans, the causative agent of skin lesions called Buruli ulcers. Mycolactone-mediated activation of neural (N) Wiskott-Aldrich syndrome proteins (WASP) induces defects in cell adhesion underpinning cytotoxicity and disease pathogenesis. We describe the chemical synthesis of 23 novel mycolactone analogues that differ in structure and modular assembly of the lactone core with its northern and southern polyketide side chains. The lactone core linked to southern chain was the minimal structure binding N-WASP and hematopoietic homolog WASP, where the number and configuration of hydroxyl groups on the acyl side chain impacted the degree of binding. A fluorescent derivative of this compound showed time-dependent accumulation in target cells. Furthermore, a simplified version of mycolactone mimicked the natural toxin for activation of WASP in vitro and induced comparable alterations of epithelial cell adhesion. Therefore, it constitutes a structural and functional surrogate of mycolactone for WASP/N-WASP-dependent effects.
Collapse
Affiliation(s)
- Anne-Caroline Chany
- Laboratoire de Chimie Organique et Bioorganique, Université de Haute-Alsace, ENSCMu , 3 Rue A. Werner, 68093 Mulhouse Cedex, France
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Chany AC, Tresse C, Casarotto V, Blanchard N. History, biology and chemistry of Mycobacterium ulcerans infections (Buruli ulcer disease). Nat Prod Rep 2014; 30:1527-67. [PMID: 24178858 DOI: 10.1039/c3np70068b] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Mycobacterium ulcerans infections (Buruli ulcer disease) have a long history that can be traced back 150 years. The successive discoveries of the mycobacteria in 1948 and of mycolactone A/B in 1999, the toxin responsible for this dramatic necrotic skin disease, resulted in a paradigm shift concerning the disease itself and in a broader sense, delineated an entirely new role for bioactive polyketides as virulence factors. The fascinating history, biology and chemistry of M. ulcerans infections are discussed in this review.
Collapse
Affiliation(s)
- Anne-Caroline Chany
- Université de Haute Alsace, Laboratoire de Chimie Organique et Bioorganique, EA4566, Ecole Nationale Supérieure de Chimie de Mulhouse, 3 rue Alfred Werner, 68093 Mulhouse Cedex, France
| | | | | | | |
Collapse
|
35
|
Converse PJ, Xing Y, Kim KH, Tyagi S, Li SY, Almeida DV, Nuermberger EL, Grosset JH, Kishi Y. Accelerated detection of mycolactone production and response to antibiotic treatment in a mouse model of Mycobacterium ulcerans disease. PLoS Negl Trop Dis 2014; 8:e2618. [PMID: 24392174 PMCID: PMC3879254 DOI: 10.1371/journal.pntd.0002618] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 11/21/2013] [Indexed: 11/19/2022] Open
Abstract
Diagnosis of the neglected tropical disease, Buruli ulcer, can be made by acid-fast smear microscopy, specimen culture on mycobacterial growth media, polymerase chain reaction (PCR), and/or histopathology. All have drawbacks, including non-specificity and requirements for prolonged culture at 32°C, relatively sophisticated laboratory facilities, and expertise, respectively. The causative organism, Mycobacterium ulcerans, produces a unique toxin, mycolactone A/B (ML) that can be detected by thin layer chromatography (TLC) or mass spectrometric analysis. Detection by the latter technique requires sophisticated facilities. TLC is relatively simple but can be complicated by the presence of other lipids in the specimen. A method using a boronate-assisted fluorogenic chemosensor in TLC can overcome this challenge by selectively detecting ML when visualized with UV light. This report describes modifications in the fluorescent TLC (F-TLC) procedure and its application to the mouse footpad model of M. ulcerans disease to determine the kinetics of mycolactone production and its correlation with footpad swelling and the number of colony forming units in the footpad. The response of all three parameters to treatment with the current standard regimen of rifampin (RIF) and streptomycin (STR) or a proposed oral regimen of RIF and clarithromycin (CLR) was also assessed. ML was detectable before the onset of footpad swelling when there were <105 CFU per footpad. Swelling occurred when there were >105 CFU per footpad. Mycolactone concentrations increased as swelling increased whereas CFU levels reached a plateau. Treatment with either RIF+STR or RIF+CLR resulted in comparable reductions of mycolactone, footpad swelling, and CFU burden. Storage in absolute ethanol appears critical to successful detection of ML in footpads and would be practical for storage of clinical samples. F-TLC may offer a new tool for confirmation of suspected clinical lesions and be more specific than smear microscopy, much faster than culture, and simpler than PCR. The diagnosis of Buruli ulcer, caused by infection with Mycobacterium ulcerans, is complicated by its resemblance to other diseases that may also cause ulcers in the skin. Clinical diagnosis can be supported by microscopic detection of acid-fast bacilli in the skin, by prolonged culture of at least 8 weeks, in a dedicated incubator set at 32°C, or by the polymerase chain reaction in a well-equipped laboratory usually far from the clinic where the patient comes for treatment. The treatment involves taking two drugs, one requiring injections, every day for two months, a burden for patients and their families. Since all drugs may have side effects, it is important that the treatment be appropriate for the patient's disease. We describe a new technique to rapidly and inexpensively detect the presence of the unique toxin produced by M. ulcerans in the mouse footpad model of Buruli ulcer. We show that the toxin can be detected in footpads before the development of signs of the disease, that more toxin is produced as the disease progresses, and that toxin levels decline in mice treated with either the current standard regimen of rifampin and streptomycin or a proposed all-oral drug regimen of rifampin and clarithromycin.
Collapse
Affiliation(s)
- Paul J. Converse
- Johns Hopkins University Center for Tuberculosis Research, Baltimore, Maryland, United States of America
- * E-mail:
| | - Yalan Xing
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Ki Hyun Kim
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Sandeep Tyagi
- Johns Hopkins University Center for Tuberculosis Research, Baltimore, Maryland, United States of America
| | - Si-Yang Li
- Johns Hopkins University Center for Tuberculosis Research, Baltimore, Maryland, United States of America
| | - Deepak V. Almeida
- Johns Hopkins University Center for Tuberculosis Research, Baltimore, Maryland, United States of America
| | - Eric L. Nuermberger
- Johns Hopkins University Center for Tuberculosis Research, Baltimore, Maryland, United States of America
| | - Jacques H. Grosset
- Johns Hopkins University Center for Tuberculosis Research, Baltimore, Maryland, United States of America
| | - Yoshito Kishi
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America
| |
Collapse
|
36
|
Synthesis of the Conjugated Tetraene Acid Side Chain of Mycolactone E by Suzuki-Miyaura Cross-Coupling Reaction of Alkenyl Boronates. European J Org Chem 2013. [DOI: 10.1002/ejoc.201301484] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
37
|
Structure-activity relationship studies on the macrolide exotoxin mycolactone of Mycobacterium ulcerans. PLoS Negl Trop Dis 2013; 7:e2143. [PMID: 23556027 PMCID: PMC3610637 DOI: 10.1371/journal.pntd.0002143] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 02/14/2013] [Indexed: 01/28/2023] Open
Abstract
Background Mycolactones are a family of polyketide-derived macrolide exotoxins produced by Mycobacterium ulcerans, the causative agent of the chronic necrotizing skin disease Buruli ulcer. The toxin is synthesized by polyketide synthases encoded by the virulence plasmid pMUM. The apoptotic, necrotic and immunosuppressive properties of mycolactones play a central role in the pathogenesis of M. ulcerans. Methodology/Principal Findings We have synthesized and tested a series of mycolactone derivatives to conduct structure-activity relationship studies. Flow cytometry, fluorescence microscopy and Alamar Blue-based metabolic assays were used to assess activities of mycolactones on the murine L929 fibroblast cell line. Modifications of the C-linked upper side chain (comprising C12–C20) caused less pronounced changes in cytotoxicity than modifications in the lower C5-O-linked polyunsaturated acyl side chain. A derivative with a truncated lower side chain was unique in having strong inhibitory effects on fibroblast metabolism and cell proliferation at non-cytotoxic concentrations. We also tested whether mycolactones have antimicrobial activity and found no activity against representatives of Gram-positive (Streptococcus pneumoniae) or Gram-negative bacteria (Neisseria meningitis and Escherichia coli), the fungus Saccharomyces cerevisae or the amoeba Dictyostelium discoideum. Conclusion Highly defined synthetic compounds allowed to unambiguously compare biological activities of mycolactones expressed by different M. ulcerans lineages and may help identifying target structures and triggering pathways. Buruli ulcer is a chronic necrotizing skin disease caused by Mycobacterium ulcerans. The characteristic histopathological features of Buruli ulcer, severe destruction of subcutaneous tissue with minimal inflammation in the core of the lesion, are primarily attributed to the cytotoxic activity of mycolactone, the macrolide exotoxin of M. ulcerans. Different geographical lineages of M. ulcerans produce different structural variants of mycolactone. By using highly defined synthetic mycolactones, including both naturally occurring molecular species and additional non-natural variants, we have assessed the influence of the structure of the C-linked upper side chain and the lower C5-O-linked polyunsaturated acyl side chain on biological activity. Changes in the lower side chain affected the cytotoxic activity against mammalian cells more profoundly than changes in the upper side chain. Mycolactone A/B had no antimicrobial activity against Gram-positive and Gram-negative bacteria and was also inactive against Saccharomyces and Dictyostelium.
Collapse
|
38
|
Xing Y, Hande SM, Kishi Y. Photochemistry of Mycolactone A/B, the Causative Toxin of Buruli Ulcer. J Am Chem Soc 2012; 134:19234-9. [DOI: 10.1021/ja309215m] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yalan Xing
- Department
of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138,
United States
| | - Sudhir M. Hande
- Department
of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138,
United States
| | - Yoshito Kishi
- Department
of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138,
United States
| |
Collapse
|
39
|
Hande SM, Kazumi Y, Lai WG, Jackson KL, Maeda S, Kishi Y. Synthesis and Structure of Two New Mycolactones Isolated from M. ulcerans subsp. shinshuense. Org Lett 2012; 14:4618-21. [DOI: 10.1021/ol302072b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sudhir M. Hande
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States, Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, 3-1-24 Matsuyama, Kiyose, Tokyo, Japan, and Eisai, Inc., Andover, Massachsetts 01810, United States
| | - Yuko Kazumi
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States, Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, 3-1-24 Matsuyama, Kiyose, Tokyo, Japan, and Eisai, Inc., Andover, Massachsetts 01810, United States
| | - W. George Lai
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States, Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, 3-1-24 Matsuyama, Kiyose, Tokyo, Japan, and Eisai, Inc., Andover, Massachsetts 01810, United States
| | - Katrina L. Jackson
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States, Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, 3-1-24 Matsuyama, Kiyose, Tokyo, Japan, and Eisai, Inc., Andover, Massachsetts 01810, United States
| | - Shinji Maeda
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States, Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, 3-1-24 Matsuyama, Kiyose, Tokyo, Japan, and Eisai, Inc., Andover, Massachsetts 01810, United States
| | - Yoshito Kishi
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States, Department of Mycobacterium Reference and Research, The Research Institute of Tuberculosis, 3-1-24 Matsuyama, Kiyose, Tokyo, Japan, and Eisai, Inc., Andover, Massachsetts 01810, United States
| |
Collapse
|
40
|
Nienhuis WA, Stienstra Y, Abass KM, Tuah W, Thompson WA, Awuah PC, Awuah-Boateng NY, Adjei O, Bretzel G, Schouten JP, van der Werf TS. Paradoxical responses after start of antimicrobial treatment in Mycobacterium ulcerans infection. Clin Infect Dis 2011; 54:519-26. [PMID: 22156855 DOI: 10.1093/cid/cir856] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Antimicrobial killing in mycobacterial infections may be accompanied by (transient) clinical deterioration, known as paradoxical reaction. To search for patterns reflecting such reactions in the treatment of Buruli ulcer (Mycobacterium ulcerans infection), the evolution of lesions of patients treated with antimicrobials was prospectively assessed. METHODS The lesion size of participants of the BURULICO antimicrobial trial (with lesions ≤10 cm cross-sectional diameter) was assessed by careful palpation and recorded by serial acetate sheet tracings. Patients were treated with antimicrobials for 8 weeks. For the size analysis, participants whose treatment had failed, had skin grafting, or were coinfected with human immunodeficiency virus were excluded. For every time point, surface area was compared with the previous assessment. A generalized additive mixed model was used to study lesion evolution. Nonulcerative lesions were studied using digital images recording possible subsequent ulceration. RESULTS Of 151 participants, 134 were included in the lesion size analysis. Peak paradoxical response occurred at week 8; >30% of participants showed an increase in lesion size as compared with the previous (week 6) assessment. Seventy-five of 90 (83%) of nonulcerative lesions ulcerated after start of treatment. Nine participants developed new lesions during or after treatment. All lesions subsequently healed. CONCLUSIONS After start of antimicrobial treatment for Buruli ulcer, new or progressive ulceration is common before healing sets in. This paradoxical response, most prominent at the end of the 8-week antimicrobial treatment, should not be misinterpreted as failure to respond to treatment. Clinical Trials Registration. ClinicalTrials.gov, NCT00321178.
Collapse
Affiliation(s)
- Willemien A Nienhuis
- Department of Internal Medicine, Infectious Diseases Service and Tuberculosis Unit, University Medical Center Groningen, University of Groningen, The Netherlands
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Chany AC, Casarotto V, Schmitt M, Tarnus C, Guenin-Macé L, Demangel C, Mirguet O, Eustache J, Blanchard N. A diverted total synthesis of mycolactone analogues: an insight into Buruli ulcer toxins. Chemistry 2011; 17:14413-9. [PMID: 22127975 DOI: 10.1002/chem.201102542] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Indexed: 12/20/2022]
Abstract
Mycolactones are complex macrolides responsible for a severe necrotizing skin disease called Buruli ulcer. Deciphering their functional interactions is of fundamental importance for the understanding, and ultimately, the control of this devastating mycobacterial infection. We report herein a diverted total synthesis approach of mycolactones analogues and provide the first insights into their structure-activity relationship based on cytopathic assays on L929 fibroblasts. The lowest concentration inducing a cytopathic effect was determined for selected analogues, allowing a clear picture to emerge by comparison with the natural toxins.
Collapse
Affiliation(s)
- Anne-Caroline Chany
- Université de Haute-Alsace, Ecole Nationale Supérieure de Chimie de Mulhouse, Laboratoire de Chimie Organique et Bioorganique EA4566, 3 rue A. Werner, 68093 Mulhouse Cedex, France
| | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Abstract
Buruli Ulcer (BU) is a neglected, necrotizing skin disease, caused by M. ulcerans, that can leave patients with prominent scars and lifelong disability. M. ulcerans produces a diffusible lipid toxin, mycolactone, essential for bacterial virulence. Prevention is difficult as little is known about disease transmission and there is no vaccine. There have been several recent advances in the field. These include sequencing of the bacterial genome and of the giant plasmid responsible for mycolactone synthesis, better understanding of the bacterial lifecycle and of the mechanism of action of the toxin. This work has revealed a number of possible vaccine candidates, some of which are shared with other mycobacteria, e.g. M. tuberculosis, while other targets are unique to M. ulcerans. In this review, we discuss several M. ulcerans vaccine targets and vaccination methods, and outline some of the gaps in our understanding of the bacterium and the immune response against it.
Collapse
|
43
|
Gersbach P, Jantsch A, Feyen F, Scherr N, Dangy JP, Pluschke G, Altmann KH. A ring-closing metathesis (RCM)-based approach to mycolactones A/B. Chemistry 2011; 17:13017-31. [PMID: 21971832 DOI: 10.1002/chem.201101799] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2011] [Indexed: 11/07/2022]
Abstract
The total synthesis of the mycobacterial toxins mycolactones A/B (1 a/b) has been accomplished based on a strategy built around the construction of the mycolactone core through ring-closing metathesis. By employing the Grubbs second-generation catalyst, the 12-membered core macrocycle of mycolactones, with a functionalized C2 handle attached to C11, was obtained in 60-80 % yield. The C-linked upper side chain (comprising C12-C20) was completed by a highly efficient modified Suzuki coupling between C13 and C14, while the attachment of the C5-O-linked polyunsaturated acyl side chain was achieved by Yamaguchi esterification. Surprisingly, a diene containing a simple isopropyl group attached to C11 could not be induced to undergo ring-closing metathesis. By employing fluorescence microscopy and flow cytometry techniques, the synthetic mycolactones A/B (1 a/b) were demonstrated to display similar apoptosis-inducing and cytopathic effects as mycolactones A/B extracted from Mycobacterium ulcerans. In contrast, a simplified analogue with truncated upper and lower side chains was found to be inactive.
Collapse
Affiliation(s)
- Philipp Gersbach
- Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH) Zürich, HCI H405, Wolfgang-Pauli-Str. 10, 8093 Zürich, Switzerland
| | | | | | | | | | | | | |
Collapse
|