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Akolgo GA, Partridge BM, D Craggs T, Amewu RK. Alternative boronic acids in the detection of Mycolactone A/B using the thin layer chromatography (f-TLC) method for diagnosis of Buruli ulcer. BMC Infect Dis 2023; 23:495. [PMID: 37501134 PMCID: PMC10373253 DOI: 10.1186/s12879-023-08426-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 06/25/2023] [Indexed: 07/29/2023] Open
Abstract
BACKGROUND Mycobacterium ulcerans is the causative agent of Buruli ulcer. The pathology of M. ulcerans disease has been attributed to the secretion of a potent macrolide cytotoxin known as mycolactone which plays an important role in the virulence of the disease. Mycolactone is a biomarker for the diagnosis of BU that can be detected using the fluorescent-thin layer chromatography (f-TLC) technique. The technique relies on the chemical derivatization of mycolactone A/B with 2-naphthylboronic acid (BA) which acts as a fluorogenic chemosensor. However, background interferences due to co-extracted human tissue lipids, especially with clinical samples coupled with the subjectivity of the method call for an investigation to find an alternative to BA. METHODS Twenty-six commercially available arylboronic acids were initially screened as alternatives to BA using the f-TLC experiment. UV-vis measurements were also conducted to determine the absorption maximum spectra of mycolactone A/B and myco-boronic acid adducts followed by an investigation of the fluorescence-enhancing ability of the boronate ester formation between mycolactone A/B and our three most promising boronic acids (BA15, BA18, and BA21). LC-MS technique was employed to confirm the adduct formation between mycolactone and boronic acids. Furthermore, a comparative study was conducted between BA18 and BA using 6 Polymerase Chain Reaction (PCR) confirmed BU patient samples. RESULTS Three of the boronic acids (BA15, BA18, and BA21) produced fluorescent band intensities superior to BA. Complexation studies conducted on thin layer chromatography (TLC) using 0.1 M solution of the three boronic acids and various volumes of 10 ng/µL of synthetic mycolactone ranging from 1 µL - 9 µL corresponding to 10 ng - 90 ng gave similar results with myco-BA18 adduct emerging with the most visibly intense fluorescence bands. UV-vis absorption maxima (λmax) for the free mycolactone A/B was observed at 362 nm, and the values for the adducts myco-BA15, myco-BA18, and myco-BA21 were at 272 nm, 270 nm, and 286 nm respectively. The comparable experimental λmax of 362 nm for mycolactone A/B to the calculated Woodward-Fieser value of 367 nm for the fatty acid side chain of mycolactone A/B demonstrate that even though 2 cyclic boronates were formed, only the boronate of the southern side chain with the chromophore was excited by irradiation at 365 nm. Fluorescence experiments have demonstrated that coupling BA18 to mycolactone A/B along the 1,3-diols remarkably enhanced the fluorescence intensity at 537 nm. High-Resolution Mass Spectrometer (HR-MS) was used to confirm the formation of the myco-BA15 adduct. Finally, f-TLC analysis of patient samples with BA18 gave improved BA18-adduct intensities compared to the original BA-adduct. CONCLUSION Twenty-six commercially available boronic acids were investigated as alternatives to BA, used in the f-TLC analysis for the diagnosis of BU. Three (3) of them BA15, BA18, and BA21 gave superior fluorescence band intensity profiles. They gave profiles that were easier to interpret after the myco-boronic acid adduct formation and in experiments with clinical samples from patients with BA18 the best. BA18, therefore, has been identified as a potential alternative to BA and could provide a solution to the challenge of background interference of co-extracted human tissue lipids from clinical samples currently associated with the use of BA.
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Grants
- (164187, University of Sheffield, RBV1, UG) Global Challenges Research Fund
- (164187, University of Sheffield, RBV1, UG) Global Challenges Research Fund
- (164187, University of Sheffield, RBV1, UG) Global Challenges Research Fund
- (164187, University of Sheffield, RBV1, UG) Global Challenges Research Fund
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Affiliation(s)
- Gideon A Akolgo
- Department of Chemistry, School of Physical and Mathematical Sciences, College of Basic and Applied Sciences, University of Ghana, P.O. Box LG 56, Legon, Accra, Ghana
| | - Benjamin M Partridge
- Department of Chemistry, University of Sheffield, Dainton Building, Sheffield, S3 7HF, UK
| | - Timothy D Craggs
- Department of Chemistry, University of Sheffield, Dainton Building, Sheffield, S3 7HF, UK
| | - Richard K Amewu
- Department of Chemistry, School of Physical and Mathematical Sciences, College of Basic and Applied Sciences, University of Ghana, P.O. Box LG 56, Legon, Accra, Ghana.
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2
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Amewu RK, Akolgo GA, Asare ME, Abdulai Z, Ablordey AS, Asiedu K. Evaluation of the fluorescent-thin layer chromatography (f-TLC) for the diagnosis of Buruli ulcer disease in Ghana. PLoS One 2022; 17:e0270235. [PMID: 35917367 PMCID: PMC9345483 DOI: 10.1371/journal.pone.0270235] [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: 10/22/2021] [Accepted: 06/06/2022] [Indexed: 11/18/2022] Open
Abstract
Background Buruli ulcer is a tissue necrosis infection caused by an environmental mycobacterium called Mycobacterium ulcerans (MU). The disease is most prevalent in rural areas with the highest rates in West and Central African countries. The bacterium produces a toxin called mycolactone which can lead to the destruction of the skin, resulting in incapacitating deformities with an enormous economic and social burden on patients and their caregivers. Even though there is an effective antibiotic treatment for BU, the control and management rely on early case detection and rapid diagnosis to avert morbidities. The diagnosis of Mycobacterium ulcerans relies on smear microscopy, culture histopathology, and PCR. Unfortunately, all the current laboratory diagnostics have various limitations and are not available in endemic communities. Consequently, there is a need for a rapid diagnostic tool for use at the community health centre level to enable diagnosis and confirmation of suspected cases for early treatment. The present study corroborated the diagnostic performance and utility of fluorescent-thin layer chromatography (f-TLC) for the diagnosis of Buruli ulcer. Methodology/Principal findings The f-TLC method was evaluated for the diagnosis of Buruli ulcer in larger clinical samples than previously reported in an earlier preliminary study Wadagni et al. (2015). A total of 449 patients suspected of BU were included in the final data analysis out of which 122 (27.2%) were positive by f-TLC and 128 (28.5%) by PCR. Using a composite reference method generated from the two diagnostic methods, 85 (18.9%) patients were found to be truly infected with M. ulcerans, 284 (63.3%) were uninfected, while 80 (17.8%) were misidentified as infected or noninfected by the two methods. The data obtained was used to determine the discriminatory accuracy of the f-TLC against the gold standard IS2404 PCR through the analysis of its sensitivity, specificity, positive (+LR), and negative (–LR) likelihood ratio. The positive (PPV) and negative (NPV) predictive values, area under the receiver operating characteristic curve Azevedo et al. (2014), and diagnostic odds ratio were used to assess the predictive accuracy of the f-TLC method. The sensitivity of f-TLC was 66.4% (85/128), specificity was 88.5% (284/321), while the diagnostic accuracy was 82.2% (369/449). The AUC stood at 0.774 while the PPV, NPV, +LR, and–LR were 69.7% (85/122), 86.9% (284/327), 5.76, and 0.38, respectively. The use of the rule-of-thumb interpretation of diagnostic tests suggests that the method is good for use as a diagnostic tool. Conclusions/Significance Larger clinical samples than previously reported had been used to evaluate the f-TLC method for the diagnosis of Buruli ulcer. A sensitivity of 66.4%, a specificity of 88.5%, and diagnostic accuracy of 82.2% were obtained. The method is good for diagnosis and will help in making early clinical decisions about the patients as well as patient management and facilitating treatment decisions. However, it requires a slight modification to address the challenge of background interference and lack of automatic readout to become an excellent diagnostic tool.
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Affiliation(s)
- Richard K. Amewu
- Department of Chemistry, University of Ghana, Accra, Ghana
- * E-mail:
| | | | | | - Zigli Abdulai
- Department of Chemistry, University of Ghana, Accra, Ghana
| | - Anthony S. Ablordey
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Kingsley Asiedu
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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3
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Rifflet A, Demangel C, Guenin-Macé L. Mycolactone Purification from M. ulcerans Cultures and HPLC-Based Approaches for Mycolactone Quantification in Biological Samples. Methods Mol Biol 2022; 2387:117-130. [PMID: 34643908 DOI: 10.1007/978-1-0716-1779-3_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Mycolactones are a family of polyketide synthase products made by the human pathogen Mycobacterium ulcerans that were recently identified as novel inhibitors of the host membrane translocation complex (Sec61). Here, we provide protocols for the purification of mycolactones from bacterial cultures, and for their quantitative assessment in biological samples.
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Affiliation(s)
- Aline Rifflet
- Biology and Genetics of Bacterial Cell Wall, Institut Pasteur, Paris, France
- INSERM, Equipe Avenir, Paris, France
| | - Caroline Demangel
- Immunobiology of Infection Unit, Institut Pasteur, INSERM U1221, Paris, France
| | - Laure Guenin-Macé
- Immunobiology of Infection Unit, Institut Pasteur, INSERM U1221, Paris, France.
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4
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Amewu RK, Spangenberg T. Detection of Mycolactone by Thin Layer Chromatography. Methods Mol Biol 2022; 2387:131-149. [PMID: 34643909 DOI: 10.1007/978-1-0716-1779-3_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
By means of thin layer chromatography coupled to a fluorescence enhancer, a highly sensitive and operationally simple method to detect the mycolactones stemming from the human pathogen Mycobacterium ulcerans was developed and applied to various sample sources.
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Affiliation(s)
| | - Thomas Spangenberg
- Global Health Institute of Merck, Ares Trading S.A. (a subsidiary of Merck KGaA Darmstadt Germany), Eysins, Switzerland
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5
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Tello Rubio B, Bugault F, Baudon B, Raynal B, Brûlé S, Morel JD, Saint-Auret S, Blanchard N, Demangel C, Guenin-Macé L. Molecular Mechanisms Underpinning the Circulation and Cellular Uptake of Mycobacterium ulcerans Toxin Mycolactone. Front Pharmacol 2021; 12:733496. [PMID: 34603049 PMCID: PMC8481864 DOI: 10.3389/fphar.2021.733496] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/06/2021] [Indexed: 11/13/2022] Open
Abstract
Mycolactone is a diffusible lipid toxin produced by Mycobacterium ulcerans, the causative agent of Buruli ulcer disease. Altough bacterially derived mycolactone has been shown to traffic from cutaneous foci of infection to the bloodstream, the mechanisms underpinning its access to systemic circulation and import by host cells remain largely unknown. Using biophysical and cell-based approaches, we demonstrate that mycolactone specific association to serum albumin and lipoproteins is necessary for its solubilization and is a major mechanism to regulate its bioavailability. We also demonstrate that Scavenger Receptor (SR)-B1 contributes to the cellular uptake of mycolactone. Overall, we suggest a new mechanism of transport and cell entry, challenging the dogma that the toxin enters host cells via passive diffusion.
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Affiliation(s)
- Bruno Tello Rubio
- Immunobiology of Infection Unit, INSERM U1221, Institut Pasteur, Paris, France
| | - Florence Bugault
- Immunobiology of Infection Unit, INSERM U1221, Institut Pasteur, Paris, France
| | - Blandine Baudon
- Immunobiology of Infection Unit, INSERM U1221, Institut Pasteur, Paris, France
| | - Bertrand Raynal
- Plateforme de Biophysique Moléculaire, UMR 3528 CNRS, Institut Pasteur, Paris, France
| | - Sébastien Brûlé
- Plateforme de Biophysique Moléculaire, UMR 3528 CNRS, Institut Pasteur, Paris, France
| | - Jean-David Morel
- Immunobiology of Infection Unit, INSERM U1221, Institut Pasteur, Paris, France
| | - Sarah Saint-Auret
- CNRS, LIMA, UMR 7042, Université de Haute-Alsace, Université de Strasbourg, Mulhouse, France
| | - Nicolas Blanchard
- CNRS, LIMA, UMR 7042, Université de Haute-Alsace, Université de Strasbourg, Mulhouse, France
| | - Caroline Demangel
- Immunobiology of Infection Unit, INSERM U1221, Institut Pasteur, Paris, France
| | - Laure Guenin-Macé
- Immunobiology of Infection Unit, INSERM U1221, Institut Pasteur, Paris, France
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6
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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.
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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
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7
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Colucci-Guyon E, Rifflet A, Saint-Auret S, da Costa A, Boucontet L, Laval T, Prehaud C, Blanchard N, Levraud JP, Boneca IG, Demangel C, Guenin-Macé L. Spatiotemporal analysis of mycolactone distribution in vivo reveals partial diffusion in the central nervous system. PLoS Negl Trop Dis 2020; 14:e0008878. [PMID: 33264290 PMCID: PMC7710047 DOI: 10.1371/journal.pntd.0008878] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 10/13/2020] [Indexed: 01/26/2023] Open
Abstract
Mycobacterium ulcerans, the causative agent of Buruli ulcer (BU) disease, is unique amongst human pathogens in its capacity to produce a lipid toxin called mycolactone. While previous studies have demonstrated that bacterially-released mycolactone diffuses beyond infection foci, the spatiotemporal distribution of mycolactone remained largely unknown. Here, we used the zebrafish model to provide the first global kinetic analysis of mycolactone's diffusion in vivo, and multicellular co-culture systems to address the critical question of the toxin's access to the brain. Zebrafish larvae were injected with a fluorescent-derivative of mycolactone to visualize the in vivo diffusion of the toxin from the peripheral circulation. A rapid, body-wide distribution of mycolactone was observed, with selective accumulation in tissues near the injection site and brain, together with an important excretion through the gastro-intestinal tract. Our conclusion that mycolactone reached the central nervous system was reinforced by an in cellulo model of human blood brain barrier and a mouse model of M. ulcerans-infection. Here we show that mycolactone has a broad but heterogenous profile of distribution in vivo. Our investigations in vitro and in vivo support the view that a fraction of bacterially-produced mycolactone gains access to the central nervous system. The relative persistence of mycolactone in the bloodstream suggests that assays of circulating mycolactone are relevant for BU disease monitoring and treatment optimization.
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Affiliation(s)
- Emma Colucci-Guyon
- Macrophages and Development of Immunity, Institut Pasteur, CNRS UMR 3738, Paris, France
| | - Aline Rifflet
- Institut Pasteur, Unité Biologie et génétique de la paroi bactérienne, Paris 75724, France; CNRS, UMR 2001 “Microbiologie intégrative et moléculaire”, Paris 75015, France; INSERM, groupe Avenir, Paris, France
| | - Sarah Saint-Auret
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA, UMR 7042, Mulhouse, France
| | | | - Laurent Boucontet
- Macrophages and Development of Immunity, Institut Pasteur, CNRS UMR 3738, Paris, France
| | - Thomas Laval
- Immunobiology of Infection Unit, Institut Pasteur, INSERM U1221, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | | | - Nicolas Blanchard
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA, UMR 7042, Mulhouse, France
| | - Jean-Pierre Levraud
- Macrophages and Development of Immunity, Institut Pasteur, CNRS UMR 3738, Paris, France
| | - Ivo G. Boneca
- Institut Pasteur, Unité Biologie et génétique de la paroi bactérienne, Paris 75724, France; CNRS, UMR 2001 “Microbiologie intégrative et moléculaire”, Paris 75015, France; INSERM, groupe Avenir, Paris, France
| | - Caroline Demangel
- Immunobiology of Infection Unit, Institut Pasteur, INSERM U1221, Paris, France
| | - Laure Guenin-Macé
- Immunobiology of Infection Unit, Institut Pasteur, INSERM U1221, Paris, France
- * E-mail:
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8
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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.
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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.
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9
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Morel JD, Paatero AO, Wei J, Yewdell JW, Guenin-Macé L, Van Haver D, Impens F, Pietrosemoli N, Paavilainen VO, Demangel C. Proteomics Reveals Scope of Mycolactone-mediated Sec61 Blockade and Distinctive Stress Signature. Mol Cell Proteomics 2018; 17:1750-1765. [PMID: 29915147 DOI: 10.1074/mcp.ra118.000824] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 06/17/2018] [Indexed: 11/06/2022] Open
Abstract
Mycolactone is a bacteria-derived macrolide that blocks the biogenesis of a large array of secretory and integral transmembrane proteins (TMP) through potent inhibition of the Sec61 translocon. Here, we used quantitative proteomics to delineate the direct and indirect effects of mycolactone-mediated Sec61 blockade in living cells. In T lymphocytes, dendritic cells and sensory neurons, Sec61 substrates downregulated by mycolactone were in order of incidence: secretory proteins (with a signal peptide but no transmembrane domain), TMPs with a signal peptide (Type I) and TMPs without signal peptide and a cytosolic N terminus (Type II). TMPs without a signal peptide and the opposite N terminus topology (Type III) were refractory to mycolactone inhibition. This rule applied comparably to single- and multi-pass TMPs, and extended to exogenous viral proteins. Parallel to its broad-spectrum inhibition of Sec61-mediated protein translocation, mycolactone rapidly induced cytosolic chaperones Hsp70/Hsp90. Moreover, it activated an atypical endoplasmic reticulum stress response, differing from conventional unfolded protein response by the down-regulation of Bip. In addition to refining our mechanistic understanding of Sec61 inhibition by mycolactone, our findings thus reveal that Sec61 blockade induces proteostatic stress in the cytosol and the endoplasmic reticulum.
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Affiliation(s)
- Jean-David Morel
- From the ‡Immunobiology of Infection Unit, Institut Pasteur, 75015 Paris, France.,§INSERM, U1221, 75005 Paris, France
| | - Anja O Paatero
- ¶Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Jiajie Wei
- ‖Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Jonathan W Yewdell
- ‖Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Laure Guenin-Macé
- From the ‡Immunobiology of Infection Unit, Institut Pasteur, 75015 Paris, France.,§INSERM, U1221, 75005 Paris, France
| | - Delphi Van Haver
- **VIB-UGent Center for Medical Biotechnology, 9000 Ghent, Belgium.,‡‡VIB Proteomics Core, 9000 Ghent, Belgium.,§§Department of Biochemistry, Ghent University, 9000 Ghent, Belgium
| | - Francis Impens
- **VIB-UGent Center for Medical Biotechnology, 9000 Ghent, Belgium.,‡‡VIB Proteomics Core, 9000 Ghent, Belgium.,§§Department of Biochemistry, Ghent University, 9000 Ghent, Belgium
| | - Natalia Pietrosemoli
- ¶¶Bioinformatics and Biostatistics Hub, Center of Bioinformatics, Biostatistics, and Integrative Biology, Institut Pasteur, Unité de Service et de Recherche 3756 Institut Pasteur CNRS, 75015 Paris, France
| | - Ville O Paavilainen
- ¶Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Caroline Demangel
- From the ‡Immunobiology of Infection Unit, Institut Pasteur, 75015 Paris, France; .,§INSERM, U1221, 75005 Paris, France
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10
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van der Werf TS. Diagnostic Tests for Buruli Ulcer: Clinical Judgment Revisited. Clin Infect Dis 2018. [DOI: 10.1093/cid/ciy203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Tjip S van der Werf
- Infectious Diseases Division, Internal Medicine, and Pulmonary Diseases and Tuberculosis, University of Groningen, University Medical Center Groningen, The Netherlands
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11
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Isaac C, Mauborgne A, Grimaldi A, Ade K, Pohl M, Limatola C, Boucher Y, Demangel C, Guenin-Macé L. Mycolactone displays anti-inflammatory effects on the nervous system. PLoS Negl Trop Dis 2017; 11:e0006058. [PMID: 29149212 PMCID: PMC5693295 DOI: 10.1371/journal.pntd.0006058] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 10/20/2017] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Mycolactone is a macrolide produced by the skin pathogen Mycobacterium ulcerans, with cytotoxic, analgesic and immunomodulatory properties. The latter were recently shown to result from mycolactone blocking the Sec61-dependent production of pro-inflammatory mediators by immune cells. Here we investigated whether mycolactone similarly affects the inflammatory responses of the nervous cell subsets involved in pain perception, transmission and maintenance. We also investigated the effects of mycolactone on the neuroinflammation that is associated with chronic pain in vivo. METHODOLOGY/ PRINCIPLE FINDINGS Sensory neurons, Schwann cells and microglia were isolated from mice for ex vivo assessment of mycolactone cytotoxicity and immunomodulatory activity by measuring the production of proalgesic cytokines and chemokines. In all cell types studied, prolonged (>48h) exposure to mycolactone induced significant cell death at concentrations >10 ng/ml. Within the first 24h treatment, nanomolar concentrations of mycolactone efficiently suppressed the cell production of pro-inflammatory mediators, without affecting their viability. Notably, mycolactone also prevented the pro-inflammatory polarization of cortical microglia. Since these cells critically contribute to neuroinflammation, we next tested if mycolactone impacts this pathogenic process in vivo. We used a rat model of neuropathic pain induced by chronic constriction of the sciatic nerve. Here, mycolactone was injected daily for 3 days in the spinal canal, to ensure its proper delivery to spinal cord. While this treatment failed to prevent injury-induced neuroinflammation, it decreased significantly the local production of inflammatory cytokines without inducing detectable cytotoxicity. CONCLUSION/ SIGNIFICANCE The present study provides in vitro and in vivo evidence that mycolactone suppresses the inflammatory responses of sensory neurons, Schwann cells and microglia, without affecting the cell viability. Together with previous studies using peripheral blood leukocytes, our work implies that mycolactone-mediated analgesia may, at least partially, be explained by its anti-inflammatory properties.
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Affiliation(s)
- Caroline Isaac
- Institut Pasteur, Unité d’Immunobiologie de l’Infection, Paris, France
- INSERM U1221, Paris, France
| | - Annie Mauborgne
- Centre de Psychiatrie et Neurosciences, Inserm U894, Paris, France
| | - Alfonso Grimaldi
- Pasteur Institute Rome, Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Kemy Ade
- Institut Pasteur, Unité d’Immunobiologie de l’Infection, Paris, France
- INSERM U1221, Paris, France
| | - Michel Pohl
- Centre de Psychiatrie et Neurosciences, Inserm U894, Paris, France
| | - Cristina Limatola
- Pasteur Institute Rome, Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
- IRCCS Neuromed, Pozzilli, Italy
| | - Yves Boucher
- Centre de Psychiatrie et Neurosciences, Inserm U894, Paris, France
- Groupe Hospitalier Pitié Salpétrière, UFR Odontologie Université Paris Diderot, Paris, France
| | - Caroline Demangel
- Institut Pasteur, Unité d’Immunobiologie de l’Infection, Paris, France
- INSERM U1221, Paris, France
| | - Laure Guenin-Macé
- Institut Pasteur, Unité d’Immunobiologie de l’Infection, Paris, France
- INSERM U1221, Paris, France
- * E-mail:
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12
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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.
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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
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13
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Sec61 blockade by mycolactone inhibits antigen cross-presentation independently of endosome-to-cytosol export. Proc Natl Acad Sci U S A 2017; 114:E5910-E5919. [PMID: 28679634 DOI: 10.1073/pnas.1705242114] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Although antigen cross-presentation in dendritic cells (DCs) is critical to the initiation of most cytotoxic immune responses, the intracellular mechanisms and traffic pathways involved are still unclear. One of the most critical steps in this process, the export of internalized antigen to the cytosol, has been suggested to be mediated by Sec61. Sec61 is the channel that translocates signal peptide-bearing nascent polypeptides into the endoplasmic reticulum (ER), and it was also proposed to mediate protein retrotranslocation during ER-associated degradation (a process called ERAD). Here, we used a newly identified Sec61 blocker, mycolactone, to analyze Sec61's contribution to antigen cross-presentation, ERAD, and transport of internalized antigens into the cytosol. As shown previously in other cell types, mycolactone prevented protein import into the ER of DCs. Mycolactone-mediated Sec61 blockade also potently suppressed both antigen cross-presentation and direct presentation of synthetic peptides to CD8+ T cells. In contrast, it did not affect protein export from the ER lumen or from endosomes into the cytosol, suggesting that the inhibition of cross-presentation was not related to either of these trafficking pathways. Proteomic profiling of mycolactone-exposed DCs showed that expression of mediators of antigen presentation, including MHC class I and β2 microglobulin, were highly susceptible to mycolactone treatment, indicating that Sec61 blockade affects antigen cross-presentation indirectly. Together, our data suggest that the defective translocation and subsequent degradation of Sec61 substrates is the cause of altered antigen cross-presentation in Sec61-blocked DCs.
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14
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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.
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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
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15
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Baron L, Paatero AO, Morel JD, Impens F, Guenin-Macé L, Saint-Auret S, Blanchard N, Dillmann R, Niang F, Pellegrini S, Taunton J, Paavilainen VO, Demangel C. Mycolactone subverts immunity by selectively blocking the Sec61 translocon. J Exp Med 2016; 213:2885-2896. [PMID: 27821549 PMCID: PMC5154940 DOI: 10.1084/jem.20160662] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 08/26/2016] [Accepted: 10/17/2016] [Indexed: 12/29/2022] Open
Abstract
Mycolactone, an immunosuppressive macrolide released by the human pathogen Mycobacterium ulcerans, was previously shown to impair Sec61-dependent protein translocation, but the underlying molecular mechanism was not identified. In this study, we show that mycolactone directly targets the α subunit of the Sec61 translocon to block the production of secreted and integral membrane proteins with high potency. We identify a single-amino acid mutation conferring resistance to mycolactone, which localizes its interaction site near the lumenal plug of Sec61α. Quantitative proteomics reveals that during T cell activation, mycolactone-mediated Sec61 blockade affects a selective subset of secretory proteins including key signal-transmitting receptors and adhesion molecules. Expression of mutant Sec61α in mycolactone-treated T cells rescued their homing potential and effector functions. Furthermore, when expressed in macrophages, the mycolactone-resistant mutant restored IFN-γ receptor-mediated antimicrobial responses. Thus, our data provide definitive genetic evidence that Sec61 is the host receptor mediating the diverse immunomodulatory effects of mycolactone and identify Sec61 as a novel regulator of immune cell functions.
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Affiliation(s)
- Ludivine Baron
- Unité d’Immunobiologie de l’Infection, Institut Pasteur, Institut National de la Santé et de la Recherche Médicale U1221, 75015 Paris, France
| | | | - Jean-David Morel
- Unité d’Immunobiologie de l’Infection, Institut Pasteur, Institut National de la Santé et de la Recherche Médicale U1221, 75015 Paris, France
| | - Francis Impens
- Unité des Interactions Bactéries-Cellules, Institut Pasteur, Institut National de la Santé et de la Recherche Médicale U604, Institut National de la Recherche Agronomique, Unité sous-contrat 2020, 75015 Paris, France
| | - Laure Guenin-Macé
- Unité d’Immunobiologie de l’Infection, Institut Pasteur, Institut National de la Santé et de la Recherche Médicale U1221, 75015 Paris, France
| | - Sarah Saint-Auret
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7509, École européenne de Chimie, Polymères et Matériaux, Université de Strasbourg, 67087 Strasbourg, France
| | - Nicolas Blanchard
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7509, École européenne de Chimie, Polymères et Matériaux, Université de Strasbourg, 67087 Strasbourg, France
| | - Rabea Dillmann
- Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Fatoumata Niang
- Unité d’Immunobiologie de l’Infection, Institut Pasteur, Institut National de la Santé et de la Recherche Médicale U1221, 75015 Paris, France
| | - Sandra Pellegrini
- Unité de Signalisation des Cytokines, Institut Pasteur, Institut National de la Santé et de la Recherche Médicale U1221, 75015 Paris, France
| | - Jack Taunton
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158
| | | | - Caroline Demangel
- Unité d’Immunobiologie de l’Infection, Institut Pasteur, Institut National de la Santé et de la Recherche Médicale U1221, 75015 Paris, France
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16
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Sakyi SA, Aboagye SY, Otchere ID, Liao AM, Caltagirone TG, Yeboah-Manu D. RNA Aptamer That Specifically Binds to Mycolactone and Serves as a Diagnostic Tool for Diagnosis of Buruli Ulcer. PLoS Negl Trop Dis 2016; 10:e0004950. [PMID: 27776120 PMCID: PMC5077154 DOI: 10.1371/journal.pntd.0004950] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 08/03/2016] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Buruli ulcer (BU) is a subcutaneous skin disease listed among the neglected tropical diseases by the World Health Organization (WHO). Early case detection and management is very important to reduce morbidity and the accompanied characteristic disfiguring nature of BU. Since diagnosis based on clinical evidence can lead to misdiagnosis, microbiological confirmation is essential to reduce abuse of drugs; since the anti-mycobacterial drugs are also used for TB treatment. The current WHO gold standard PCR method is expensive, requires infrastructure and expertise are usually not available at the peripheral centers where BU cases are managed. Thus one of the main research agendas is to develop methods that can be applied at the point of care. In this study we selected aptamers, which are emerging novel class of detection molecules, for detecting mycolactone, the first to be conducted in a BUD endemic country. METHODS Aptamers that bind to mycolactone were isolated by the SELEX process. To measure their affinity and specificity to mycolactone, the selected aptamers were screened by means of isothermal titration calorimetry (ITC) and an enzyme-linked oligonucleotide assay (ELONA). Selected aptamers were assessed by ELONA using swab samples from forty-one suspected BU patients with IS2404 PCR and culture as standard methods. ROC analysis was used to evaluate their accuracy and cutoff-points. RESULTS Five out of the nine selected aptamers bound significantly (p< 0.05) to mycolactone, of these, three were able to distinguish between mycolactone producing mycobacteria, M. marinum (CC240299, Israel) and other bacteria whilst two others also bounded significantly to Mycobacterium smegmatis. Their dissociation constants were in the micro-molar range. At 95% confidence interval, the ROC curve analysis among the aptamers at OD450 ranged from 0.5-0.7. Using this cut-off for the ELONA assay, the aptamers had 100% specificity and sensitivity between 0.0% and 50.0%. The most promising aptamer, Apt-3683 showed a discernible cleavage difference relative to the non-specific autocatalysis over a 3-minute time course. CONCLUSION This preliminary proof-of-concept indicates that diagnosis of BUD with RNA aptamers is feasible and can be used as point of care upon incorporation into a diagnostic platform.
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Affiliation(s)
- Samuel A. Sakyi
- Department of Molecular Medicine, School of Medical Sciences, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
- * E-mail:
| | - Samuel Yaw Aboagye
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Isaac Darko Otchere
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Accra, Ghana
| | - Albert M. Liao
- Aptagen LLC, Jacobus, Pennsylvania, United States of America
| | | | - Dorothy Yeboah-Manu
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Accra, Ghana
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17
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Sarfo FS, Phillips R, Wansbrough-Jones M, Simmonds RE. Recent advances: role of mycolactone in the pathogenesis and monitoring of Mycobacterium ulcerans infection/Buruli ulcer disease. Cell Microbiol 2016; 18:17-29. [PMID: 26572803 PMCID: PMC4705457 DOI: 10.1111/cmi.12547] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 11/10/2015] [Accepted: 11/13/2015] [Indexed: 02/03/2023]
Abstract
Infection of subcutaneous tissue with Mycobacterium ulcerans can lead to chronic skin ulceration known as Buruli ulcer. The pathogenesis of this neglected tropical disease is dependent on a lipid‐like toxin, mycolactone, which diffuses through tissue away from the infecting organisms. Since its identification in 1999, this molecule has been intensely studied to elucidate its cytotoxic and immunosuppressive properties. Two recent major advances identifying the underlying molecular targets for mycolactone have been described. First, it can target scaffolding proteins (such as Wiskott Aldrich Syndrome Protein), which control actin dynamics in adherent cells and therefore lead to detachment and cell death by anoikis. Second, it prevents the co‐translational translocation (and therefore production) of many proteins that pass through the endoplasmic reticulum for secretion or placement in cell membranes. These pleiotropic effects underpin the range of cell‐specific functional defects in immune and other cells that contact mycolactone during infection. The dose and duration of mycolactone exposure for these different cells explains tissue necrosis and the paucity of immune cells in the ulcers. This review discusses recent advances in the field, revisits older findings in this context and highlights current developments in structure‐function studies as well as methodology that make mycolactone a promising diagnostic biomarker.
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Affiliation(s)
- Fred Stephen Sarfo
- Department of Medicine, Kwame Nkrumah University of Science & Technology, Kumasi, Ghana
| | - Richard Phillips
- Department of Medicine, Kwame Nkrumah University of Science & Technology, Kumasi, Ghana
| | - Mark Wansbrough-Jones
- Division of Cellular and Molecular Medicine, St George's, University of London, London, UK
| | - Rachel E Simmonds
- School of Biosciences and Medicine, University of Surrey, Guildford, UK
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18
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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.
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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.
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19
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Niang F, Sarfo FS, Frimpong M, Guenin-Macé L, Wansbrough-Jones M, Stinear T, Phillips RO, Demangel C. Metabolomic profiles delineate mycolactone signature in Buruli ulcer disease. Sci Rep 2015; 5:17693. [PMID: 26634444 PMCID: PMC4669498 DOI: 10.1038/srep17693] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 11/02/2015] [Indexed: 11/09/2022] Open
Abstract
Infection of human skin with Mycobacterium ulcerans, the causative agent of Buruli ulcer, is associated with the systemic diffusion of a bacterial macrolide named mycolactone. Patients with progressive disease show alterations in their serum proteome, likely reflecting the inhibition of secreted protein production by mycolactone at the cellular level. Here, we used semi-quantitative metabolomics to characterize metabolic perturbations in serum samples of infected individuals, and human cells exposed to mycolactone. Among the 430 metabolites profiled across 20 patients and 20 healthy endemic controls, there were significant differences in the serum levels of hexoses, steroid hormones, acylcarnitines, purine, heme, bile acids, riboflavin and lysolipids. In parallel, analysis of 292 metabolites in human T cells treated or not with mycolactone showed alterations in hexoses, lysolipids and purine catabolites. Together, these data demonstrate that M. ulcerans infection causes systemic perturbations in the serum metabolome that can be ascribed to mycolactone. Of particular importance to Buruli ulcer pathogenesis is that changes in blood sugar homeostasis in infected patients are mirrored by alterations in hexose metabolism in mycolactone-exposed cells.
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Affiliation(s)
- Fatoumata Niang
- Institut Pasteur, Unité d'Immunobiologie de l'Infection, Paris, France.,CNRS URA 1961, Paris, France
| | | | | | - Laure Guenin-Macé
- Institut Pasteur, Unité d'Immunobiologie de l'Infection, Paris, France.,CNRS URA 1961, Paris, France
| | | | - Timothy Stinear
- University of Melbourne, Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Richard O Phillips
- Komfo Anokye Teaching Hospital, Kumasi, Ghana.,Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Caroline Demangel
- Institut Pasteur, Unité d'Immunobiologie de l'Infection, Paris, France.,CNRS URA 1961, Paris, France
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20
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Wadagni A, Frimpong M, Phanzu DM, Ablordey A, Kacou E, Gbedevi M, Marion E, Xing Y, Babu VS, Phillips RO, Wansbrough-Jones M, Kishi Y, Asiedu K. Simple, Rapid Mycobacterium ulcerans Disease Diagnosis from Clinical Samples by Fluorescence of Mycolactone on Thin Layer Chromatography. PLoS Negl Trop Dis 2015; 9:e0004247. [PMID: 26583925 PMCID: PMC4652903 DOI: 10.1371/journal.pntd.0004247] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 10/28/2015] [Indexed: 11/25/2022] Open
Abstract
Introduction Mycobacterium ulcerans infection, known as Buruli ulcer, is a disease of the skin and subcutaneous tissues which is an important but neglected tropical disease with its major impact in rural parts of West and Central Africa where facilities for diagnosis and management are poorly developed. We evaluated fluorescent thin layer chromatography (f-TLC) for detection of mycolactone in the laboratory using samples from patients with Buruli ulcer and patients with similar lesions that gave a negative result on PCR for the IS2404 repeat sequence of M. ulcerans Methodology/Principal findings Mycolactone and DNA extracts from fine needle aspiration (FNA), swabs and biopsy specimen were used to determine the sensitivity and specificity of f-TLC when compared with PCR for the IS2404. For 71 IS2404 PCR positive and 28 PCR negative samples the sensitivity was 73.2% and specificity of 85.7% for f-TLC. The sensitivity was similar for swabs (73%), FNAs (75%) and biopsies (70%). Conclusions We have shown that mycolactone can be detected from M. ulcerans infected skin tissue by f-TLC technique. The technique is simple, easy to perform and read with minimal costs. In this study it was undertaken by a member of the group from each endemic country. It is a potentially implementable tool at the district level after evaluation in larger field studies. Mycobacterium ulcerans infection, known as Buruli ulcer, is a disease that affects the skin and underlying tissues. The organism responsible for the infection produces a potent toxin called mycolactone that causes extensive skin damage. Easy to perform and cheaper techniques are needed for diagnostic confirmation. We have evaluated fluorescent thin layer chromatography (fTLC) for detection of mycolactone in skin samples from patients with Buruli ulcer comparing them with samples from similar non-Buruli ulcer lesions that gave a negative result in the standard polymerase chain reaction (PCR) test for M. ulcerans. Fluorescent TLC had sensitivity of 73.2% and specificity of 85.7% when compared with PCR whether the skin sample was a swab, a biopsy or a fine needle aspirate. This study shows that mycolactone can be detected reliably from M. ulcerans infected skin tissue by the simple, low cost technique of fluorescent thin layer chromatography that could be developed for point of care use. It requires further evaluation in countries where Buruli ulcer disease is endemic.
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Affiliation(s)
- Anita Wadagni
- Centre de Dépistage et de Traitement de l’Ulcère de Buruli d’Allada, Allada, Bénin
| | - Michael Frimpong
- Kumasi Centre for Collaborative Research in Tropical Medicine (KCCR), Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
| | | | - Anthony Ablordey
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | | | - Mirabelle Gbedevi
- Centre de Dépistage et de Traitement de l’Ulcère de Buruli d’Allada, Allada, Bénin
| | - Estelle Marion
- Centre de Diagnostic et de Traitement de l'Ulcère de Buruli de Pobè, Fondation Raoul Follereau, Pobè, Bénin
| | - Yalan Xing
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Vaddela Sudheer Babu
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Richard Odame Phillips
- Kumasi Centre for Collaborative Research in Tropical Medicine (KCCR), Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
- Department of Medicine, School of Medical Sciences, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
- * E-mail:
| | | | - Yoshito Kishi
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Kingsley Asiedu
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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21
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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.
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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).
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22
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Geroult S, Phillips R, Demangel C. Adhesion of the ulcerative pathogenMycobacterium ulceransto DACC-coated dressings. J Wound Care 2014; 23:417-8, 422-4. [DOI: 10.12968/jowc.2014.23.8.417] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- S. Geroult
- Laboratory Technician, Immunology Department, Institut Pasteur, Paris, France
- Research Group Leader, CNRS URA 1961, Paris, France
| | - R.O. Phillips
- Komfo Anokye Teaching Hospital, Kumasi, Ghana
- Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - C. Demangel
- Laboratory Technician, Immunology Department, Institut Pasteur, Paris, France
- Research Group Leader, CNRS URA 1961, Paris, France
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23
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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.
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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
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24
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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.
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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
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25
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Guenin-Macé L, Veyron-Churlet R, Thoulouze MI, Romet-Lemonne G, Hong H, Leadlay PF, Danckaert A, Ruf MT, Mostowy S, Zurzolo C, Bousso P, Chrétien F, Carlier MF, Demangel C. Mycolactone activation of Wiskott-Aldrich syndrome proteins underpins Buruli ulcer formation. J Clin Invest 2013; 123:1501-12. [PMID: 23549080 DOI: 10.1172/jci66576] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 01/29/2013] [Indexed: 12/30/2022] Open
Abstract
Mycolactone is a diffusible lipid secreted by the human pathogen Mycobacterium ulcerans, which induces the formation of open skin lesions referred to as Buruli ulcers. Here, we show that mycolactone operates by hijacking the Wiskott-Aldrich syndrome protein (WASP) family of actin-nucleating factors. By disrupting WASP autoinhibition, mycolactone leads to uncontrolled activation of ARP2/3-mediated assembly of actin in the cytoplasm. In epithelial cells, mycolactone-induced stimulation of ARP2/3 concentrated in the perinuclear region, resulting in defective cell adhesion and directional migration. In vivo injection of mycolactone into mouse ears consistently altered the junctional organization and stratification of keratinocytes, leading to epidermal thinning, followed by rupture. This degradation process was efficiently suppressed by coadministration of the N-WASP inhibitor wiskostatin. These results elucidate the molecular basis of mycolactone activity and provide a mechanism for Buruli ulcer pathogenesis. Our findings should allow for the rationale design of competitive inhibitors of mycolactone binding to N-WASP, with anti-Buruli ulcer therapeutic potential.
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Affiliation(s)
- Laure Guenin-Macé
- Institut Pasteur, Unité d'Immunobiologie de l'Infection, Paris, France
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26
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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
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27
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Marion E, Prado S, Cano C, Babonneau J, Ghamrawi S, Marsollier L. Photodegradation of the Mycobacterium ulcerans toxin, mycolactones: considerations for handling and storage. PLoS One 2012; 7:e33600. [PMID: 22514607 PMCID: PMC3326021 DOI: 10.1371/journal.pone.0033600] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Accepted: 02/13/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Mycolactones are toxins secreted by M. ulcerans, the etiological agent of Buruli ulcer. These toxins, which are the main virulence factors of the bacilli, are responsible for skin lesions. Considering their specificity for M. ulcerans and their presence in skin lesions even at early stages, mycolactones are promising candidates for the development of a diagnostic tool for M. ulcerans infection. Stability of purified mycolactones towards light and heat has not yet been investigated, despite the importance of such parameters in the selection of strategies for a diagnosis tool development. In this context, the effects of UV, light and temperature on mycolactone stability and biological activity were studied. METHODOLOGY/PRINCIPAL FINDINGS To investigate the effect of these physical parameters, mycolactones were exposed to different wavelengths in several solvents and temperatures. Structural changes and biological activity were monitored. Whilst high temperature had no effect on mycolactones, UV irradiation (UV-A, UV-B and UV-C) and sunlight exposure caused a considerable degradation, as revealed by LC-MS and NMR analysis, correlated with a loss of biological activity. Moreover, effect of UVs on mycolactone caused a photodegradation rather than a phototransformation due to the identification of degradation product. CONCLUSION/SIGNIFICANCE This study demonstrates the high sensitivity of mycolactones to UVs as such it defines instructions for storage and handling.
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Affiliation(s)
- Estelle Marion
- Unité Inserm U892, Équipe 15, Nantes-Angers, France
- Groupe d'Etude des Interactions Hôte Pathogène, Université et CHU d'Angers, Angers, France
- * E-mail: (LM); (EM)
| | - Soizic Prado
- Museum National d'Histoire Naturelle de Paris, Paris, France
| | - Camille Cano
- Unité Inserm U892, Équipe 15, Nantes-Angers, France
| | | | - Sarah Ghamrawi
- Groupe d'Etude des Interactions Hôte Pathogène, Université et CHU d'Angers, Angers, France
| | - Laurent Marsollier
- Unité Inserm U892, Équipe 15, Nantes-Angers, France
- Groupe d'Etude des Interactions Hôte Pathogène, Université et CHU d'Angers, Angers, France
- * E-mail: (LM); (EM)
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28
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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.
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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
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29
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Sarfo FS, Le Chevalier F, Aka N, Phillips RO, Amoako Y, Boneca IG, Lenormand P, Dosso M, Wansbrough-Jones M, Veyron-Churlet R, Guenin-Macé L, Demangel C. Mycolactone diffuses into the peripheral blood of Buruli ulcer patients--implications for diagnosis and disease monitoring. PLoS Negl Trop Dis 2011; 5:e1237. [PMID: 21811642 PMCID: PMC3139662 DOI: 10.1371/journal.pntd.0001237] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Accepted: 05/25/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Mycobacterium ulcerans, the causative agent of Buruli ulcer (BU), is unique among human pathogens in its capacity to produce a polyketide-derived macrolide called mycolactone, making this molecule an attractive candidate target for diagnosis and disease monitoring. Whether mycolactone diffuses from ulcerated lesions in clinically accessible samples and is modulated by antibiotic therapy remained to be established. METHODOLOGY/PRINCIPAL FINDING Peripheral blood and ulcer exudates were sampled from patients at various stages of antibiotic therapy in Ghana and Ivory Coast. Total lipids were extracted from serum, white cell pellets and ulcer exudates with organic solvents. The presence of mycolactone in these extracts was then analyzed by a recently published, field-friendly method using thin layer chromatography and fluorescence detection. This approach did not allow us to detect mycolactone accurately, because of a high background due to co-extracted human lipids. We thus used a previously established approach based on high performance liquid chromatography coupled to mass spectrometry. By this means, we could identify structurally intact mycolactone in ulcer exudates and serum of patients, and evaluate the impact of antibiotic treatment on the concentration of mycolactone. CONCLUSIONS/SIGNIFICANCE Our study provides the proof of concept that assays based on mycolactone detection in serum and ulcer exudates can form the basis of BU diagnostic tests. However, the identification of mycolactone required a technology that is not compatible with field conditions and point-of-care assays for mycolactone detection remain to be worked out. Notably, we found mycolactone in ulcer exudates harvested at the end of antibiotic therapy, suggesting that the toxin is eliminated by BU patients at a slow rate. Our results also indicated that mycolactone titres in the serum may reflect a positive response to antibiotics, a possibility that it will be interesting to examine further through longitudinal studies.
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Affiliation(s)
| | | | - N'Guetta Aka
- Institut Pasteur, Mycobactéries Tuberculeuses et Atypiques, Abidjan, Côte d'Ivoire
| | - Richard O. Phillips
- Komfo Anokye Teaching Hospital, Kumasi, Ghana
- Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Yaw Amoako
- Komfo Anokye Teaching Hospital, Kumasi, Ghana
| | - Ivo G. Boneca
- Institut Pasteur, Biologie et Génétique de la Paroi Bactérienne, Paris, France
- INSERM, Groupe AVENIR, Paris, France
| | | | - Mireille Dosso
- Institut Pasteur, Mycobactéries Tuberculeuses et Atypiques, Abidjan, Côte d'Ivoire
| | | | | | - Laure Guenin-Macé
- Institut Pasteur, Pathogénomique Mycobactérienne Intégrée, Paris, France
| | - Caroline Demangel
- Institut Pasteur, Pathogénomique Mycobactérienne Intégrée, Paris, France
- * E-mail:
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30
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Abstract
Buruli ulcer is a severe and devastating skin disease caused by Mycobacterium ulcerans infection, yet it is one of the most neglected diseases. The causative toxin, referred to as mycolactone A/B, was isolated and characterized as a polyketide-derived macrolide in 1999. The current status of the mycolactone chemistry is described, highlighting the stereochemistry assignment of mycolactone A/B; total synthesis; the structure determination of mycolactone congeners from the human pathogen M. ulcerans, the frog pathogen Mycobacterium liflandii, and the fish pathogen Mycobacterium marinum; the structural diversity in the mycolactone class of natural products; the highly sensitive detection/structure-analysis of mycolactones; and some biological activity.
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31
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Khan SA, Singh AK, Senapati D, Fan Z, Ray PC. Bio-conjugated popcorn shaped gold nanoparticles for targeted photothermal killing of multiple drug resistant Salmonella DT104. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm13320a] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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32
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Khan SA, Singh AK, Senapati D, Fan Z, Ray PC. Targeted highly sensitive detection of multi-drug resistant salmonella DT104 using gold nanoparticles. Chem Commun (Camb) 2011; 47:9444-6. [DOI: 10.1039/c1cc13199k] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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