1
|
Kusza DA, Venter GA, Mabunda M, Biwi J, Samanta SK, Klinck JD, Singh SV, Hunter R, Kaschula CH. Finding the Ajoene Sweet-Spot: Structure-Activity Relations that Govern its Blood Stability and Cancer Cytotoxicity. ChemMedChem 2024; 19:e202400087. [PMID: 38532643 DOI: 10.1002/cmdc.202400087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 03/15/2024] [Accepted: 03/19/2024] [Indexed: 03/28/2024]
Abstract
Ajoene is an organosulfur compound found in crushed garlic that exerts its anti-cancer activity by S-thiolating cysteine residues on proteins. Its development is hampered due to limited bioavailability, so in this study, we synthesised analogues of ajoene to probe the significance of the ajoene vinyl disulfide/sulfoxide core with respect to cytotoxicity and blood stability. Polar side groups were also incorporated to improve aqueous solubility. It was found that derivatives containing a vinyl disulfide functional group (4-7, as in ajoene), were more cytotoxic compared to analogues in which the double bond was removed, although the latter showed superior blood stability. It was also found that the allyl-S sulfur of the disulfide was more electrophilic to S-thiolysis based on the global electrophilicity index (ω) and the condensed electrophilic Fukui functionf k + ${{ f}_{\rm{k}}^{\rm{ + }} }$ . S-Thiolysis was found to be exergonic for the vinyl disulfides based on entropy and enthalpy computations with a deprotonated thiolate. Derivatisation to the dihydro (10, 12) and deoxydihydroajoenes (9, 11) produced analogues that were slightly less potent but with greatly improved blood stability. Taken together, the deoxydihydroajoenes present themselves as good candidates for further therapeutic development.
Collapse
Affiliation(s)
- Daniel A Kusza
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town, 7701, South Africa
| | - Gerhard A Venter
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town, 7701, South Africa
| | - Mandla Mabunda
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town, 7701, South Africa
| | - James Biwi
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town, 7701, South Africa
| | - Suman K Samanta
- Faculty of Science, Assam down town University, Sankar Madhab Path, Gandi Nagar, Panikhaiti, Guwahati, 781026, Assam, India
| | - Johan D Klinck
- Department of Chemistry and Polymer Science, Stellenbosch University, Matieland, 7600, South Africa
| | - Shivendra V Singh
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- University of Pittsburgh School of Medicine, UPMC Hillman Cancer Centre, Pittsburgh, Pennsylvania, USA
| | - Roger Hunter
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town, 7701, South Africa
| | - Catherine H Kaschula
- Department of Chemistry and Polymer Science, Stellenbosch University, Matieland, 7600, South Africa
| |
Collapse
|
2
|
Janzing NBM, Senges CHR, Dietze P, Haltli B, Marchbank DH, Kerr RG, Bandow JE. Mechanism of action of pseudopteroxazole and pseudopterosin G: Diterpenes from marine origin. Proteomics 2024; 24:e2300390. [PMID: 38158717 DOI: 10.1002/pmic.202300390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024]
Abstract
Pseudopteroxazole (Ptx) and the pseudopterosins are marine natural products with promising antibacterial potential. While Ptx has attracted interest for its antimycobacterial activity, pseudopterosins are active against several clinically relevant pathogens. Both compound classes exhibit low cytotoxicity and accessibility to targeted synthesis, yet their antibacterial mechanisms remain elusive. In this study, we investigated the modes of action of Ptx and pseudopterosin G (PsG) in Bacillus subtilis employing an unbiased approach that combines gel-based proteomics with a mathematical similarity analysis of response profiles. Proteomic responses to sublethal concentrations of Ptx and PsG were compared to a library of antibiotic stress response profiles revealing that both induce a stress response characteristic for agents targeting the bacterial cell envelope by interfering with membrane-bound steps of cell wall biosynthesis. Microscopy-based assays confirmed that both compounds compromise the integrity of the bacterial cell wall without disrupting the membrane potential. Furthermore, LC-MSE analysis showed that the greater potency of PsG against B. subtilis, reflected in a lower MIC and a more pronounced proteomic response, may be rooted in a more effective association with and penetration of B. subtilis cells. We conclude that Ptx and PsG target the integrity of the gram-positive cell wall.
Collapse
Affiliation(s)
- Niklas B M Janzing
- Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Christoph H R Senges
- Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Pascal Dietze
- Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Bradley Haltli
- University of Prince Edward Island, Charlottetown, PE, Canada
- Nautilus Biosciences Croda, Charlottetown, Canada
| | - Douglas H Marchbank
- University of Prince Edward Island, Charlottetown, PE, Canada
- Nautilus Biosciences Croda, Charlottetown, Canada
| | - Russell G Kerr
- University of Prince Edward Island, Charlottetown, PE, Canada
| | - Julia E Bandow
- Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| |
Collapse
|
3
|
Nazaret F, Alloing G, Mandon K, Frendo P. MarR Family Transcriptional Regulators and Their Roles in Plant-Interacting Bacteria. Microorganisms 2023; 11:1936. [PMID: 37630496 PMCID: PMC10458429 DOI: 10.3390/microorganisms11081936] [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: 06/23/2023] [Revised: 07/25/2023] [Accepted: 07/26/2023] [Indexed: 08/27/2023] Open
Abstract
The relationship between plants and associated soil microorganisms plays a major role in ecosystem functioning. Plant-bacteria interactions involve complex signaling pathways regulating various processes required by bacteria to adapt to their fluctuating environment. The establishment and maintenance of these interactions rely on the ability of the bacteria to sense and respond to biotic and abiotic environmental signals. In this context, MarR family transcriptional regulators can use these signals for transcriptional regulation, which is required to establish adapted responses. MarR-like transcriptional regulators are essential for the regulation of the specialized functions involved in plant-bacteria interactions in response to a wide range of molecules associated with the plant host. The conversion of environmental signals into changes in bacterial physiology and behavior allows the bacteria to colonize the plant and ensure a successful interaction. This review focuses on the mechanisms of plant-signal perception by MarR-like regulators, namely how they (i) allow bacteria to cope with the rhizosphere and plant endosphere, (ii) regulate the beneficial functions of Plant-Growth-Promoting Bacteria and (iii) regulate the virulence of phytopathogenic bacteria.
Collapse
Affiliation(s)
| | | | | | - Pierre Frendo
- Université Côte d’Azur, INRAE, CNRS, ISA, 06903 Sophia Antipolis, France; (F.N.); (G.A.); (K.M.)
| |
Collapse
|
4
|
Insight into the Cold Adaptation Mechanism of an Aerobic Denitrifying Bacterium: Bacillus simplex H-b. Appl Environ Microbiol 2023; 89:e0192822. [PMID: 36656033 PMCID: PMC9972999 DOI: 10.1128/aem.01928-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Psychrophilic bacteria with aerobic denitrification ability have promising potential for application in nitrogen-contaminated wastewater treatment, especially under cold conditions. A better understanding of the cold adaptation mechanism during aerobic denitrification would be beneficial for the practical application of this type of functional bacterium. In this study, Bacillus simplex H-b with good denitrification performance at 5°C was used to investigate the corresponding cold tolerance mechanism. Transcriptomics and nitrogen removal characterization experiments were conducted at different temperatures (5°C, 20°C, and 30°C). At low temperatures, more nitrogen was utilized for assimilation, accompanied by the accumulation of ATP and extracellular polymeric substances (EPS), rather than transforming inorganic nitrogen in the dissimilation pathway. In addition, the proportion of unsaturated fatty acids was higher in strains cultured at low temperatures. At the molecular level, the adjustment of membrane transport, synthesis of cofactors and vitamins, and transcriptional regulators might contribute to the survival of the strain under cold conditions. Moreover, nucleotide precursor synthesis, translation, and oxidative and temperature stress response mechanisms also enhanced the resistance of strain H-b to low temperatures. The results suggest that combining multiple regulatory mechanisms and synergistic adaptation to cold stress enabled the growth and relatively high nitrogen removal rate (27.22%) of strain H-b at 5°C. By clarifying the mechanism of regulation and cold resistance of strain H-b, a theoretical foundation for enhancing the application potential of this functional bacterium for nitrogen-contaminated wastewater treatment was provided. IMPORTANCE The newly isolated aerobic denitrifying bacterium Bacillus simplex H-b removed various forms of inorganic nitrogen (nitrate, nitrite, and ammonium) from wastewater, even when the temperature was as low as 5°C. Although this environmentally functional bacterium has been suggested as a promising candidate for nitrogen-contaminated water treatment at low temperatures, understanding its cold adaptation mechanism during aerobic denitrification is limited. In this study, the cold tolerance mechanism of this strain was comprehensively explained. Furthermore, a theoretical basis for the practical application of this type of functional bacterium for nitrogen removal in cold regions is provided. The study expands our understanding of the survival strategy of psychrophilic bacteria and hence supports their further utilization in wastewater treatment applications.
Collapse
|
5
|
Sánchez-Gloria JL, Rada KM, Juárez-Rojas JG, Sánchez-Lozada LG, Rubio-Gayosso I, Sánchez-Muñoz F, Osorio-Alonso H. Role of Sulfur Compounds in Garlic as Potential Therapeutic Option for Inflammation and Oxidative Stress in Asthma. Int J Mol Sci 2022; 23:ijms232415599. [PMID: 36555240 PMCID: PMC9779154 DOI: 10.3390/ijms232415599] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/17/2022] [Accepted: 11/25/2022] [Indexed: 12/13/2022] Open
Abstract
Asthma is a chronic inflammatory disease in the airways with a multifactorial origin but with inflammation and oxidative stress as related pathogenic mechanisms. Garlic (Allium sativum) is a nutraceutical with different biological properties due to sulfur-containing natural compounds. Studies have shown that several compounds in garlic may have beneficial effects on cardiovascular diseases, including those related to the lungs. Therefore, it is possible to take advantage of the compounds from garlic as nutraceuticals for treating lung diseases. The objective of this article is to review the biological properties of the sulfur compounds present in garlic for the treatment of asthma, as well as the cellular mechanisms involved. Here, we discuss the potential therapeutic effects of garlic compounds in the modulation of inflammation and oxidative stress, as well as its antibiotic and antiviral activities for identifying and testing potential treatment options for asthma management.
Collapse
Affiliation(s)
- José L. Sánchez-Gloria
- Sección de Estudios de Posgrado, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico City 11340, Mexico
- Departamento de Inmunología, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City 14080, Mexico
| | - Karla M. Rada
- Sección de Estudios de Posgrado, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico City 11340, Mexico
- Departamento de Inmunología, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City 14080, Mexico
| | - Juan G. Juárez-Rojas
- Departamento de Endocrinología, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City 14080, Mexico
| | - Laura G. Sánchez-Lozada
- Departamento de Fisiopatología Cardio-Renal, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City 14080, Mexico
| | - Ivan Rubio-Gayosso
- Sección de Estudios de Posgrado, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico City 11340, Mexico
| | - Fausto Sánchez-Muñoz
- Departamento de Inmunología, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City 14080, Mexico
| | - Horacio Osorio-Alonso
- Departamento de Fisiopatología Cardio-Renal, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City 14080, Mexico
- Correspondence: or
| |
Collapse
|
6
|
Kusza DA, Hunter R, Schäfer G, Smith M, Katz AA, Kaschula CH. Activity-Based Proteomic Identification of the S-Thiolation Targets of Ajoene in MDA-MB-231 Breast Cancer Cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:14679-14692. [PMID: 36351177 DOI: 10.1021/acs.jafc.2c04972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Garlic is a medicinal plant and spice that has been used for millennia for its health-promoting effects. These medicinal properties are associated with low molecular weight organosulfur compounds, produced following the crushing of garlic cloves. One of these compounds, ajoene, is proposed to act by S-thioallylating cysteine residues on target proteins whose identification in cancer cells holds great promise for understanding mechanistic aspects of ajoene's cancer cell cytotoxicity. To this end, an ajoene analogue (called biotin-ajoene, BA), containing a biotin affinity tag, was designed as an activity-based probe specific for the protein targets of ajoene in MDA-MB-231 breast cancer cells. BA was synthesized via a convergent "click" strategy and found to retain its cytotoxicity against MDA-MB-231 cells compared to ajoene. Widespread biotinylation of proteins was found to occur via disulfide bond formation in a dose-dependent manner, and the biotin-ajoene probe was found to share the same protein targets as its parent compound, ajoene. The biotinylated proteins were affinity-purified from the treated MDA-MB-231 cell lysate using streptavidin-coated magnetic beads followed by an on-bead reduction, alkylation, and digestion to liberate the peptide fragments, which were analyzed by liquid chromatography tandem mass chromatography. A total of 600 protein targets were identified, among which 91% overlapped with proteins with known protein cysteine modification (PCM) sites. The specific sites were enriched for those susceptible to S-glutathionylation (-SSG) (16%), S-sulfhydration (-SSH) (20%), S-sulfenylation (-SOH) (22%), and S-nitrosylation (-SNO) (31%). As target validation, both ajoene and a dansylated ajoene (DP) were found to S-thiolate the pure recombinant forms of glutathione S-transferase pi 1 (GSTP1) and protein disulfide isomerase (PDI), and the ajoene analogue DP was found to be a more potent inhibitor than 5,5-dithio-bis-(2-nitrobenzoic acid) (DTNB). Pathway analysis elucidated that ajoene targets functional and signaling pathways that are implicated in cancer cell survival, specifically cellular processes, metabolism, and genetic information processing pathways. The results of this study provide mechanistic insights into the character of the anti-cancer activity of the natural dietary compound ajoene.
Collapse
Affiliation(s)
- Daniel A Kusza
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town 7700, South Africa
| | - Roger Hunter
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town 7700, South Africa
| | - Georgia Schäfer
- International Centre for Genetic Engineering and Biotechnology, Observatory, Cape Town 7925, South Africa
- Department of Integrative Biomedical Sciences, University of Cape Town, Observatory, Cape Town 7925, South Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, Cape Town 7925, South Africa
| | - Muneerah Smith
- Department of Integrative Biomedical Sciences, University of Cape Town, Observatory, Cape Town 7925, South Africa
| | - Arieh A Katz
- Department of Integrative Biomedical Sciences, University of Cape Town, Observatory, Cape Town 7925, South Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, Cape Town 7925, South Africa
- SA-MRC-UCT Gynaecological Cancer Research Centre, University of Cape Town, Cape Town 7925, South Africa
| | - Catherine H Kaschula
- Department of Chemistry and Polymer Science, Stellenbosch University, Matieland 7600, South Africa
| |
Collapse
|
7
|
Mengers HG, Schier C, Zimmermann M, C. H. Gruhlke M, Block E, Blank LM, Slusarenko AJ. Seeing the smell of garlic: Detection of gas phase volatiles from crushed garlic (Allium sativum), onion (Allium cepa), ramsons (Allium ursinum) and human garlic breath using SESI-Orbitrap MS. Food Chem 2022; 397:133804. [DOI: 10.1016/j.foodchem.2022.133804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 07/05/2022] [Accepted: 07/25/2022] [Indexed: 12/01/2022]
|
8
|
Qiu ZE, Xu JB, Chen L, Huang ZX, Lei TL, Huang ZY, Hou XC, Yang HL, Lin QH, Zhu YX, Zhao L, Zhou WL, Zhang YL. Allicin Facilitates Airway Surface Liquid Hydration by Activation of CFTR. Front Pharmacol 2022; 13:890284. [PMID: 35784719 PMCID: PMC9241074 DOI: 10.3389/fphar.2022.890284] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Accepted: 05/20/2022] [Indexed: 11/16/2022] Open
Abstract
Airway epithelium plays critical roles in regulating airway surface liquid (ASL), the alteration of which causes mucus stasis symptoms. Allicin is a compound released from garlic and harbors the capacity of lung-protection. However, the potential regulatory effects of allicin on airway epithelium remain elusive. This study aimed to investigate the effects of allicin on ion transport across airway epithelium and evaluate its potential as an expectorant. Application of allicin induced Cl− secretion across airway epithelium in a concentration-dependent manner. Blockade of cystic fibrosis transmembrane conductance regulator (CFTR) or inhibition of adenylate cyclase-cAMP signaling pathway attenuated allicin-induced Cl− secretion in airway epithelial cells. The in vivo study showed that inhaled allicin significantly increased the ASL secretion in mice. These results suggest that allicin induces Cl− and fluid secretion across airway epithelium via activation of CFTR, which might provide therapeutic strategies for the treatment of chronic pulmonary diseases associated with ASL dehydration.
Collapse
Affiliation(s)
- Zhuo-Er Qiu
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Jian-Bang Xu
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, China
| | - Lei Chen
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Ze-Xin Huang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Tian-Lun Lei
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Zi-Yang Huang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Xiao-Chun Hou
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Hai-Long Yang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Qin-Hua Lin
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yun-Xin Zhu
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Lei Zhao
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, China
- Department of Physiology, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China
- *Correspondence: Lei Zhao, ; Wen-Liang Zhou, ; Yi-Lin Zhang,
| | - Wen-Liang Zhou
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- *Correspondence: Lei Zhao, ; Wen-Liang Zhou, ; Yi-Lin Zhang,
| | - Yi-Lin Zhang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
- *Correspondence: Lei Zhao, ; Wen-Liang Zhou, ; Yi-Lin Zhang,
| |
Collapse
|
9
|
Matavacas J, von Wachenfeldt C. Update on the Protein Homeostasis Network in Bacillus subtilis. Front Microbiol 2022; 13:865141. [PMID: 35350626 PMCID: PMC8957991 DOI: 10.3389/fmicb.2022.865141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 02/15/2022] [Indexed: 11/13/2022] Open
Abstract
Protein homeostasis is fundamental to cell function and survival. It relies on an interconnected network of processes involving protein synthesis, folding, post-translational modification and degradation as well as regulators of these processes. Here we provide an update on the roles, regulation and subcellular localization of the protein homeostasis machinery in the Gram-positive model organism Bacillus subtilis. We discuss emerging ideas and current research gaps in the field that, if tackled, increase our understanding of how Gram-positive bacteria, including several human pathogens, maintain protein homeostasis and cope with stressful conditions that challenge their survival.
Collapse
|
10
|
Fakhoury JN, Zhang Y, Edmonds KA, Bringas M, Luebke JL, Gonzalez-Gutierrez G, Capdevila DA, Giedroc DP. Functional asymmetry and chemical reactivity of CsoR family persulfide sensors. Nucleic Acids Res 2021; 49:12556-12576. [PMID: 34755876 PMCID: PMC8643695 DOI: 10.1093/nar/gkab1040] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 10/12/2021] [Accepted: 10/14/2021] [Indexed: 01/14/2023] Open
Abstract
CstR is a persulfide-sensing member of the functionally diverse copper-sensitive operon repressor (CsoR) superfamily. While CstR regulates the bacterial response to hydrogen sulfide (H2S) and more oxidized reactive sulfur species (RSS) in Gram-positive pathogens, other dithiol-containing CsoR proteins respond to host derived Cu(I) toxicity, sometimes in the same bacterial cytoplasm, but without regulatory crosstalk in cells. It is not clear what prevents this crosstalk, nor the extent to which RSS sensors exhibit specificity over other oxidants. Here, we report a sequence similarity network (SSN) analysis of the entire CsoR superfamily, which together with the first crystallographic structure of a CstR and comprehensive mass spectrometry-based kinetic profiling experiments, reveal new insights into the molecular basis of RSS specificity in CstRs. We find that the more N-terminal cysteine is the attacking Cys in CstR and is far more nucleophilic than in a CsoR. Moreover, our CstR crystal structure is markedly asymmetric and chemical reactivity experiments reveal the functional impact of this asymmetry. Substitution of the Asn wedge between the resolving and the attacking thiol with Ala significantly decreases asymmetry in the crystal structure and markedly impacts the distribution of species, despite adopting the same global structure as the parent repressor. Companion NMR, SAXS and molecular dynamics simulations reveal that the structural and functional asymmetry can be traced to fast internal dynamics of the tetramer. Furthermore, this asymmetry is preserved in all CstRs and with all oxidants tested, giving rise to markedly distinct distributions of crosslinked products. Our exploration of the sequence, structural, and kinetic features that determine oxidant-specificity suggest that the product distribution upon RSS exposure is determined by internal flexibility.
Collapse
Affiliation(s)
- Joseph N Fakhoury
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave, Bloomington, IN 47405-7102, USA
| | - Yifan Zhang
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave, Bloomington, IN 47405-7102, USA.,Department of Molecular and Cellular Biochemistry, Indiana University, 212 S. Hawthorne Drive, Bloomington, IN 47405 USA
| | - Katherine A Edmonds
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave, Bloomington, IN 47405-7102, USA
| | - Mauro Bringas
- Fundación Instituto Leloir, Av. Patricias Argentinas 435, Buenos Aires C1405BWE, Argentina
| | - Justin L Luebke
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave, Bloomington, IN 47405-7102, USA
| | - Giovanni Gonzalez-Gutierrez
- Department of Molecular and Cellular Biochemistry, Indiana University, 212 S. Hawthorne Drive, Bloomington, IN 47405 USA
| | - Daiana A Capdevila
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave, Bloomington, IN 47405-7102, USA.,Fundación Instituto Leloir, Av. Patricias Argentinas 435, Buenos Aires C1405BWE, Argentina
| | - David P Giedroc
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave, Bloomington, IN 47405-7102, USA.,Department of Molecular and Cellular Biochemistry, Indiana University, 212 S. Hawthorne Drive, Bloomington, IN 47405 USA
| |
Collapse
|
11
|
Mösbauer K, Fritsch VN, Adrian L, Bernhardt J, Gruhlke MCH, Slusarenko AJ, Niemeyer D, Antelmann H. The Effect of Allicin on the Proteome of SARS-CoV-2 Infected Calu-3 Cells. Front Microbiol 2021; 12:746795. [PMID: 34777295 PMCID: PMC8581659 DOI: 10.3389/fmicb.2021.746795] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 10/04/2021] [Indexed: 12/27/2022] Open
Abstract
Allicin (diallyl thiosulfinate) is the major thiol-reactive organosulfur compound produced by garlic plants (Allium sativum) upon tissue damage. Allicin exerts its strong antimicrobial activity against bacteria and fungi via S-thioallylation of protein thiols and low molecular weight thiols. Here, we investigated the effect of allicin on SARS-CoV-2 infected Vero E6 and Calu-3 cells. Toxicity tests revealed that Calu-3 cells showed greater allicin tolerance, probably due to >4-fold higher GSH levels compared to the very sensitive Vero E6 cells. Exposure of infected Vero E6 and Calu-3 cells to biocompatible allicin doses led to a ∼60–70% decrease of viral RNA and infectious viral particles. Label-free quantitative proteomics was used to investigate the changes in the Calu-3 proteome after SARS-CoV-2 infection and the effect of allicin on the host-virus proteome. SARS-CoV-2 infection of Calu-3 cells caused a strong induction of the antiviral interferon-stimulated gene (ISG) signature, including several antiviral effectors, such as cGAS, Mx1, IFIT, IFIH, IFI16, IFI44, OAS, and ISG15, pathways of vesicular transport, tight junctions (KIF5A/B/C, OSBPL2, CLTCL1, and ARHGAP17) and ubiquitin modification (UBE2L3/5), as well as reprogramming of host metabolism, transcription and translation. Allicin treatment of infected Calu-3 cells reduced the expression of IFN signaling pathways and ISG effectors and reverted several host pathways to levels of uninfected cells. Allicin further reduced the abundance of the structural viral proteins N, M, S and ORF3 in the host-virus proteome. In conclusion, our data demonstrate the antiviral and immunomodulatory activity of biocompatible doses of allicin in SARS-CoV-2-infected cell cultures. Future drug research should be directed to exploit the thiol-reactivity of allicin derivatives with increased stability and lower human cell toxicity as antiviral lead compounds.
Collapse
Affiliation(s)
- Kirstin Mösbauer
- Institute of Virology, Berlin Institute of Health, Charité-Universitätsmedizin Berlin, Freie Universität Berlin, Berlin, Germany.,German Centre for Infection Research (DZIF), Berlin, Germany
| | | | - Lorenz Adrian
- Department Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Leipzig, Germany.,Fachgebiet Geobiotechnologie, Technische Universität Berlin, Berlin, Germany
| | - Jörg Bernhardt
- Institute for Microbiology, University of Greifswald, Greifswald, Germany
| | | | | | - Daniela Niemeyer
- Institute of Virology, Berlin Institute of Health, Charité-Universitätsmedizin Berlin, Freie Universität Berlin, Berlin, Germany.,German Centre for Infection Research (DZIF), Berlin, Germany
| | - Haike Antelmann
- Institute for Biology-Microbiology, Freie Universität Berlin, Berlin, Germany
| |
Collapse
|
12
|
Allicin, the Odor of Freshly Crushed Garlic: A Review of Recent Progress in Understanding Allicin's Effects on Cells. Molecules 2021; 26:molecules26061505. [PMID: 33801955 PMCID: PMC8001868 DOI: 10.3390/molecules26061505] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 03/05/2021] [Accepted: 03/06/2021] [Indexed: 12/14/2022] Open
Abstract
The volatile organic sulfur compound allicin (diallyl thiosulfinate) is produced as a defense substance when garlic (Allium sativum) tissues are damaged, for example by the activities of pathogens or pests. Allicin gives crushed garlic its characteristic odor, is membrane permeable and readily taken up by exposed cells. It is a reactive thiol-trapping sulfur compound that S-thioallylates accessible cysteine residues in proteins and low molecular weight thiols including the cellular redox buffer glutathione (GSH) in eukaryotes and Gram-negative bacteria, as well as bacillithiol (BSH) in Gram-positive firmicutes. Allicin shows dose-dependent antimicrobial activity. At higher doses in eukaryotes allicin can induce apoptosis or necrosis, whereas lower, biocompatible amounts can modulate the activity of redox-sensitive proteins and affect cellular signaling. This review summarizes our current knowledge of how bacterial and eukaryotic cells are specifically affected by, and respond to, allicin.
Collapse
|
13
|
Tran HT, Bonilla CY. SigB-regulated antioxidant functions in gram‐positive bacteria. World J Microbiol Biotechnol 2021; 37:38. [DOI: 10.1007/s11274-021-03004-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 01/12/2021] [Indexed: 12/26/2022]
|
14
|
The Sulfilimine Analogue of Allicin, S-Allyl- S-( S-allyl)- N-Cyanosulfilimine, Is Antimicrobial and Reacts with Glutathione. Antioxidants (Basel) 2020; 9:antiox9111086. [PMID: 33158268 PMCID: PMC7694261 DOI: 10.3390/antiox9111086] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 10/23/2020] [Accepted: 10/23/2020] [Indexed: 12/14/2022] Open
Abstract
When cells of garlic (Allium sativum) are disrupted by wounding, they produce the defense substance allicin (diallylthiosulfinate). Allicin is an efficient thiol trap and readily passes through cell membranes into the cytosol, where it behaves as a redox toxin by oxidizing the cellular glutathione (GSH) pool and producing S-allylmercaptoglutathione (GSSA). An N-cyanosulfilimine analogue of allicin (CSA), which was predicted to have similar reactivity towards thiol groups but be more stable in storage, was synthesized and its properties investigated. Similarly to allicin, CSA was shown to inhibit the growth of various bacteria, a fungus (baker’s yeast), and Arabidopsis roots. A chemogenetic screen showed that yeast mutants with compromised GSH levels and metabolism were hypersensitive to CSA. GSH reacted with CSA to produce allyltrisulfanylglutathione (GS3A), which was a white solid virtually insoluble in water. Yeast Δgsh1 mutants are unable to synthesize GSH because they lack the γ-glutamylcysteine synthetase (GSH1) gene, and they are unable to grow without GSH supplementation in the medium. GS3A in the growth medium supported the auxotrophic requirement for GSH in Δgsh1 mutants. This result suggests that GS3A is being reduced to GSH in vivo, possibly by the enzyme glutathione reductase (GR), which has been shown to accept GSSA as a substrate. The results suggest that CSA has a mode of action similar to allicin and is effective at similar concentrations.
Collapse
|
15
|
Borlinghaus J, Bolger A, Schier C, Vogel A, Usadel B, Gruhlke MC, Slusarenko AJ. Genetic and molecular characterization of multicomponent resistance of Pseudomonas against allicin. Life Sci Alliance 2020; 3:e202000670. [PMID: 32234751 PMCID: PMC7119367 DOI: 10.26508/lsa.202000670] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/14/2020] [Accepted: 03/16/2020] [Indexed: 01/05/2023] Open
Abstract
The common foodstuff garlic produces the potent antibiotic defense substance allicin after tissue damage. Allicin is a redox toxin that oxidizes glutathione and cellular proteins and makes garlic a highly hostile environment for non-adapted microbes. Genomic clones from a highly allicin-resistant Pseudomonas fluorescens (PfAR-1), which was isolated from garlic, conferred allicin resistance to Pseudomonas syringae and even to Escherichia coli Resistance-conferring genes had redox-related functions and were on core fragments from three similar genomic islands identified by sequencing and in silico analysis. Transposon mutagenesis and overexpression analyses revealed the contribution of individual candidate genes to allicin resistance. Taken together, our data define a multicomponent resistance mechanism against allicin in PfAR-1, achieved through horizontal gene transfer.
Collapse
Affiliation(s)
- Jan Borlinghaus
- Department of Plant Physiology, Rheinisch-Westfälische Technische Hochschule Aachen (RWTH Aachen University), Aachen, Germany
| | - Anthony Bolger
- Department of Botany, Rheinisch-Westfälische Technische Hochschule Aachen (RWTH Aachen University), Aachen, Germany
| | - Christina Schier
- Department of Plant Physiology, Rheinisch-Westfälische Technische Hochschule Aachen (RWTH Aachen University), Aachen, Germany
| | - Alexander Vogel
- Department of Botany, Rheinisch-Westfälische Technische Hochschule Aachen (RWTH Aachen University), Aachen, Germany
| | - Björn Usadel
- Department of Botany, Rheinisch-Westfälische Technische Hochschule Aachen (RWTH Aachen University), Aachen, Germany
| | - Martin Ch Gruhlke
- Department of Plant Physiology, Rheinisch-Westfälische Technische Hochschule Aachen (RWTH Aachen University), Aachen, Germany
| | - Alan J Slusarenko
- Department of Plant Physiology, Rheinisch-Westfälische Technische Hochschule Aachen (RWTH Aachen University), Aachen, Germany
| |
Collapse
|
16
|
Mourenza Á, Gil JA, Mateos LM, Letek M. Oxidative Stress-Generating Antimicrobials, a Novel Strategy to Overcome Antibacterial Resistance. Antioxidants (Basel) 2020; 9:antiox9050361. [PMID: 32357394 PMCID: PMC7278815 DOI: 10.3390/antiox9050361] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 04/22/2020] [Accepted: 04/24/2020] [Indexed: 02/07/2023] Open
Abstract
Antimicrobial resistance is becoming one of the most important human health issues. Accordingly, the research focused on finding new antibiotherapeutic strategies is again becoming a priority for governments and major funding bodies. The development of treatments based on the generation of oxidative stress with the aim to disrupt the redox defenses of bacterial pathogens is an important strategy that has gained interest in recent years. This approach is allowing the identification of antimicrobials with repurposing potential that could be part of combinatorial chemotherapies designed to treat infections caused by recalcitrant bacterial pathogens. In addition, there have been important advances in the identification of novel plant and bacterial secondary metabolites that may generate oxidative stress as part of their antibacterial mechanism of action. Here, we revised the current status of this emerging field, focusing in particular on novel oxidative stress-generating compounds with the potential to treat infections caused by intracellular bacterial pathogens.
Collapse
|