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Aggarwal S, Singh V, Chakraborty A, Cha S, Dimitriou A, de Crescenzo C, Izikson O, Yu L, Plebani R, Tzika AA, Rahme LG. Skeletal muscle mitochondrial dysfunction mediated by Pseudomonas aeruginosa quorum-sensing transcription factor MvfR: reversing effects with anti-MvfR and mitochondrial-targeted compounds. mBio 2024:e0129224. [PMID: 38860823 DOI: 10.1128/mbio.01292-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Accepted: 05/14/2024] [Indexed: 06/12/2024] Open
Abstract
Sepsis and chronic infections with Pseudomonas aeruginosa, a leading "ESKAPE" bacterial pathogen, are associated with increased morbidity and mortality and skeletal muscle atrophy. The actions of this pathogen on skeletal muscle remain poorly understood. In skeletal muscle, mitochondria serve as a crucial energy source, which may be perturbed by infection. Here, using the well-established backburn and infection model of murine P. aeruginosa infection, we deciphered the systemic impact of the quorum-sensing transcription factor MvfR (multiple virulence factor regulator) by interrogating, 5 days post-infection, its effect on mitochondrial-related functions in the gastrocnemius skeletal muscle and the outcome of the pharmacological inhibition of MvfR function and that of the mitochondrial-targeted peptide, Szeto-Schiller 31 (SS-31). Our findings show that the MvfR perturbs adenosine triphosphate generation, oxidative phosphorylation, and antioxidant response, elevates the production of reactive oxygen species, and promotes oxidative damage of mitochondrial DNA in the gastrocnemius muscle of infected mice. These impairments in mitochondrial-related functions were corroborated by the alteration of key mitochondrial proteins involved in electron transport, mitochondrial biogenesis, dynamics and quality control, and mitochondrial uncoupling. Pharmacological inhibition of MvfR using the potent anti-MvfR lead, D88, we developed, or the mitochondrial-targeted peptide SS-31 rescued the MvfR-mediated alterations observed in mice infected with the wild-type strain PA14. Our study provides insights into the actions of MvfR in orchestrating mitochondrial dysfunction in the skeletal murine muscle, and it presents novel therapeutic approaches for optimizing clinical outcomes in affected patients. IMPORTANCE Skeletal muscle, pivotal for many functions in the human body, including breathing and protecting internal organs, contains abundant mitochondria essential for maintaining cellular homeostasis during infection. The effect of Pseudomonas aeruginosa (PA) infections on skeletal muscle remains poorly understood. Our study delves into the role of a central quorum-sensing transcription factor, multiple virulence factor regulator (MvfR), that controls the expression of multiple acute and chronic virulence functions that contribute to the pathogenicity of PA. The significance of our study lies in the role of MvfR in the metabolic perturbances linked to mitochondrial functions in skeletal muscle and the effectiveness of the novel MvfR inhibitor and the mitochondrial-targeted peptide SS-31 in alleviating the mitochondrial disturbances caused by PA in skeletal muscle. Inhibiting MvfR or interfering with its effects can be a potential therapeutic strategy to curb PA virulence.
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Affiliation(s)
- Shifu Aggarwal
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Vijay Singh
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Arijit Chakraborty
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
- Shriners Hospitals for Children Boston, Boston, Massachusetts, USA
| | - Sujin Cha
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Alexandra Dimitriou
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Claire de Crescenzo
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Olivia Izikson
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Lucy Yu
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Roberto Plebani
- Department of Medical, Oral and Biotechnological Sciences, "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - A Aria Tzika
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Shriners Hospitals for Children Boston, Boston, Massachusetts, USA
| | - Laurence G Rahme
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
- Shriners Hospitals for Children Boston, Boston, Massachusetts, USA
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Aggarwal S, Singh V, Chakraborty A, Cha S, Dimitriou A, de Crescenzo C, Izikson O, Yu L, Plebani R, Tzika AA, Rahme LG. Skeletal Muscle Mitochondrial Dysfunction Mediated by Pseudomonas aeruginosa Quorum Sensing Transcription Factor MvfR: Reversing Effects with Anti-MvfR and Mitochondrial-Targeted Compounds. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.03.592480. [PMID: 38746243 PMCID: PMC11092755 DOI: 10.1101/2024.05.03.592480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Sepsis and chronic infections with Pseudomonas aeruginosa, a leading "ESKAPE" bacterial pathogen, are associated with increased morbidity and mortality and skeletal muscle atrophy. The actions of this pathogen on skeletal muscle remain poorly understood. In skeletal muscle, mitochondria serve as a crucial energy source, which may be perturbed by infection. Here, using the well-established backburn and infection model of murine P. aeruginosa infection, we deciphered the systemic impact of the quorum sensing (QS) transcription factor MvfR by interrogating five days post-infection its effect on mitochondrial-related functions in the gastrocnemius skeletal muscle and the outcome of the pharmacological inhibition of MvfR function and that of the mitochondrial-targeted peptide, Szeto-Schiller 31 (SS-31). Our findings show that the MvfR perturbs ATP generation, oxidative phosphorylation (OXPHOS), and antioxidant response, elevates the production of reactive oxygen species, and promotes oxidative damage of mitochondrial DNA in the gastrocnemius muscle of infected mice. These impairments in mitochondrial-related functions were corroborated by the alteration of key mitochondrial proteins involved in electron transport, mitochondrial biogenesis, dynamics and quality control, and mitochondrial uncoupling. Pharmacological inhibition of MvfR using the potent anti-MvfR lead, D88, we developed, or the mitochondrial-targeted peptide SS-31 rescued the MvfR- mediated alterations observed in mice infected with the wild-type strain PA14. Our study provides insights into the actions of MvfR in orchestrating mitochondrial dysfunction in the skeletal murine muscle, and it presents novel therapeutic approaches for optimizing clinical outcomes in affected patients.
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Asif M, Nocilla KA, Ngo L, Shah M, Smadi Y, Hafeez Z, Parnes M, Manson A, Glushka JN, Leach FE, Edison AS. Role of UDP-Glycosyltransferase ( ugt) Genes in Detoxification and Glycosylation of 1-Hydroxyphenazine (1-HP) in Caenorhabditis elegans. Chem Res Toxicol 2024; 37:590-599. [PMID: 38488606 PMCID: PMC11022241 DOI: 10.1021/acs.chemrestox.3c00410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/26/2024] [Accepted: 02/27/2024] [Indexed: 04/16/2024]
Abstract
Caenorhabditis elegans is a useful model organism to study the xenobiotic detoxification pathways of various natural and synthetic toxins, but the mechanisms of phase II detoxification are understudied. 1-Hydroxyphenazine (1-HP), a toxin produced by the bacterium Pseudomonas aeruginosa, kills C. elegans. We previously showed that C. elegans detoxifies 1-HP by adding one, two, or three glucose molecules in N2 worms. Our current study evaluates the roles that some UDP-glycosyltransferase (ugt) genes play in 1-HP detoxification. We show that ugt-23 and ugt-49 knockout mutants are more sensitive to 1-HP than reference strains N2 or PD1074. Our data also show that ugt-23 knockout mutants produce reduced amounts of the trisaccharide sugars, while the ugt-49 knockout mutants produce reduced amounts of all 1-HP derivatives except for the glucopyranosyl product compared to the reference strains. We characterized the structure of the trisaccharide sugar phenazines made by C. elegans and showed that one of the sugar modifications contains an N-acetylglucosamine (GlcNAc) in place of glucose. This implies broad specificity regarding UGT function and the role of genes other than ogt-1 in adding GlcNAc, at least in small-molecule detoxification.
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Affiliation(s)
- Muhammad
Zaka Asif
- Department
of Biochemistry & Molecular Biology, University of Georgia, Athens, Georgia 30602, United States
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
| | - Kelsey A. Nocilla
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
| | - Li Ngo
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
| | - Man Shah
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
| | - Yosef Smadi
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
| | - Zaki Hafeez
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
| | - Michael Parnes
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
| | - Allie Manson
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
| | - John N. Glushka
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
| | - Franklin E. Leach
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
- Department
of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Arthur S. Edison
- Department
of Biochemistry & Molecular Biology, University of Georgia, Athens, Georgia 30602, United States
- Complex
Carbohydrate Research Center, University
of Georgia, Athens, Georgia 30602, United States
- Institute
of Bioinformatics, University of Georgia, Athens, Georgia 30602, United States
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Tse-Kang S, Wani KA, Peterson ND, Page A, Pukkila-Worley R. Activation of intestinal immunity by pathogen effector-triggered aggregation of lysosomal TIR-1/SARM1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.04.569946. [PMID: 38106043 PMCID: PMC10723332 DOI: 10.1101/2023.12.04.569946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
TIR-domain proteins with enzymatic activity are essential for immunity in plants, animals, and bacteria. However, it is not known how these proteins function in pathogen sensing in animals. We discovered that a TIR-domain protein (TIR-1/SARM1) is strategically expressed on the membranes of a lysosomal sub-compartment, which enables intestinal epithelial cells in the nematode C. elegans to survey for pathogen effector-triggered host damage. We showed that a redox active virulence effector secreted by the bacterial pathogen Pseudomonas aeruginosa alkalinized and condensed a specific subset of lysosomes by inducing intracellular oxidative stress. Concentration of TIR-1/SARM1 on the surface of these organelles triggered its multimerization, which engages its intrinsic NADase activity, to activate the p38 innate immune pathway and protect the host against microbial intoxication. Thus, lysosomal TIR-1/SARM1 is a sensor for oxidative stress induced by pathogenic bacteria to activate metazoan intestinal immunity.
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Pantelic L, Bogojevic SS, Vojnovic S, Oliveira R, Lazic J, Ilic-Tomic T, Milivojevic D, Nikodinovic-Runic J. Upcycling of food waste streams to valuable biopigments pyocyanin and 1-hydroxyphenazine. Enzyme Microb Technol 2023; 171:110322. [PMID: 37722241 DOI: 10.1016/j.enzmictec.2023.110322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 08/17/2023] [Accepted: 09/05/2023] [Indexed: 09/20/2023]
Abstract
Phenazines, including pyocyanin (PYO) and 1-hydroxyphenazine (1-HP) are extracellular secondary metabolites and multifunctional pigments of Pseudomonas aeruginosa responsible for its blue-green color. These versatile molecules are electrochemically active, involved in significant biological activities giving fitness to the host, but also recognized as antimicrobial and anticancer agents. Their wider application is still limited partly due to the cost of carbon substrate for production, which can be solved by the utilization of carbon from food waste within the biorefinery concept. In this study, a variety of food waste streams (banana peel, potato peel, potato washing, stale bread, yoghurt, processed meat, boiled eggs and mixed canteen waste) was used as sole nutrient source in submerged cultures of P. aeruginosa BK25H. Stale bread was identified as the most suitable substrate to support phenazine biopigments production and bacterial growth. This was further increased in 5-liter fermenter when on average 5.2 mg L-1 of PYO and 4.4 mg L-1 of 1-HP were purified after 24 h batch cultivations from the fermentation medium consisting of homogenized stale bread in tap water. Purified biopigments showed moderate antimicrobial activity, and showed different toxicity profiles, with PYO not being toxic against Caenorhabditis elegans, a free-living soil nematode up to 300 µg mL-1 and 1-HP showing lethal effects at 75 µg mL-1. Therefore, stale bread waste stream with minimal pretreatment should be considered as suitable biorefinery feedstock, as it can support the production of valuable biopigments such as phenazines.
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Affiliation(s)
- Lena Pantelic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444a, 11000 Belgrade, Serbia
| | - Sanja Skaro Bogojevic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444a, 11000 Belgrade, Serbia
| | - Sandra Vojnovic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444a, 11000 Belgrade, Serbia
| | - Rui Oliveira
- LAQV-REQUIMTE, NOVA School of Science and Technology, NOVA University Lisbon, Largo da Torre, 2829-516 Caparica, Portugal
| | - Jelena Lazic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444a, 11000 Belgrade, Serbia
| | - Tatjana Ilic-Tomic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444a, 11000 Belgrade, Serbia
| | - Dusan Milivojevic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444a, 11000 Belgrade, Serbia
| | - Jasmina Nikodinovic-Runic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444a, 11000 Belgrade, Serbia.
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Bischer AP, Baran TM, Wojtovich AP. Reactive oxygen species drive foraging decisions in Caenorhabditis elegans. Redox Biol 2023; 67:102934. [PMID: 37864874 PMCID: PMC10616421 DOI: 10.1016/j.redox.2023.102934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/14/2023] [Accepted: 10/12/2023] [Indexed: 10/23/2023] Open
Abstract
Environmental surveillance-mediated behavior integrates multiple cues through complex signaling mechanisms. In Caenorhabditis elegans, neurons coordinate perception and response through evolutionarily conserved molecular signaling cascades to mediate attraction and avoidance behaviors. However, despite lacking eyes, C. elegans was recently reported to perceive and react to the color blue. Here, we provide an explanation for this apparent color perception. We show that internally-generated reactive oxygen species (ROS) occurring in response to light are additive to exogenous sources of ROS, such as bacterial toxins or photosensitizers. Multiple sub-threshold sources of ROS are integrated to coordinate behavioral responses to the environment with internal physiologic cues, independent of color. We further demonstrate that avoidance behavior can be blocked by antioxidants, while ROS is both sufficient and scalable to phenocopy the avoidance response. Moreover, avoidance behavior in response to ROS is plastic and reversible, suggesting it may occur through a post-translation redox modification. Blue light affects C. elegans behavior through ROS generation by endogenous flavins in a process requiring the neuronal gustatory photoreceptor like protein, LITE-1. Our results demonstrate that LITE-1 is also required for ROS-mediated avoidance of pyocyanin and light-activated photosensitizers and this role is mediated through the modification of Cys44. Overall, these findings demonstrate that ROS and LITE-1 are central mediators of C. elegans foraging behavior through integration of multiple inputs, including light.
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Affiliation(s)
- Andrew P Bischer
- Department of Anesthesiology and Perioperative Medicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Timothy M Baran
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Andrew P Wojtovich
- Department of Anesthesiology and Perioperative Medicine, University of Rochester Medical Center, Rochester, NY, 14642, USA.
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Martins AC, Virgolini MB, Ávila DS, Scharf P, Li J, Tinkov AA, Skalny AV, Bowman AB, Rocha JBT, Aschner M. Mitochondria in the Spotlight: C. elegans as a Model Organism to Evaluate Xenobiotic-Induced Dysfunction. Cells 2023; 12:2124. [PMID: 37681856 PMCID: PMC10486742 DOI: 10.3390/cells12172124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/19/2023] [Accepted: 08/20/2023] [Indexed: 09/09/2023] Open
Abstract
Mitochondria play a crucial role in cellular respiration, ATP production, and the regulation of various cellular processes. Mitochondrial dysfunctions have been directly linked to pathophysiological conditions, making them a significant target of interest in toxicological research. In recent years, there has been a growing need to understand the intricate effects of xenobiotics on human health, necessitating the use of effective scientific research tools. Caenorhabditis elegans (C. elegans), a nonpathogenic nematode, has emerged as a powerful tool for investigating toxic mechanisms and mitochondrial dysfunction. With remarkable genetic homology to mammals, C. elegans has been used in studies to elucidate the impact of contaminants and drugs on mitochondrial function. This review focuses on the effects of several toxic metals and metalloids, drugs of abuse and pesticides on mitochondria, highlighting the utility of C. elegans as a model organism to investigate mitochondrial dysfunction induced by xenobiotics. Mitochondrial structure, function, and dynamics are discussed, emphasizing their essential role in cellular viability and the regulation of processes such as autophagy, apoptosis, and calcium homeostasis. Additionally, specific toxins and toxicants, such as arsenic, cadmium, and manganese are examined in the context of their impact on mitochondrial function and the utility of C. elegans in elucidating the underlying mechanisms. Furthermore, we demonstrate the utilization of C. elegans as an experimental model providing a promising platform for investigating the intricate relationships between xenobiotics and mitochondrial dysfunction. This knowledge could contribute to the development of strategies to mitigate the adverse effects of contaminants and drugs of abuse, ultimately enhancing our understanding of these complex processes and promoting human health.
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Affiliation(s)
- Airton C. Martins
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
| | - Miriam B. Virgolini
- Departamento de Farmacología Otto Orsingher, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
- Instituto de Farmacología Experimental de Córdoba-Consejo Nacional de Investigaciones Técnicas (IFEC-CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | - Daiana Silva Ávila
- Laboratory of Biochemistry and Toxicology in Caenorhabditis Elegans, Universidade Federal do Pampa, Campus Uruguaiana, BR-472 Km 592, Uruguaiana 97500-970, RS, Brazil
| | - Pablo Scharf
- Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil
| | - Jung Li
- College of Osteopathic Medicine, Des Moines University, Des Moines, IA 50312, USA
| | - Alexey A. Tinkov
- Laboratory of Ecobiomonitoring and Quality Control, Yaroslavl State University, Yaroslavl 150003, Russia
- Laboratory of Molecular Dietetics, IM Sechenov First Moscow State Medical University (Sechenov University), Moscow 119435, Russia
| | - Anatoly V. Skalny
- Laboratory of Ecobiomonitoring and Quality Control, Yaroslavl State University, Yaroslavl 150003, Russia
- Laboratory of Molecular Dietetics, IM Sechenov First Moscow State Medical University (Sechenov University), Moscow 119435, Russia
- Peoples Friendship University of Russia (RUDN University), Moscow 117198, Russia
| | - Aaron B. Bowman
- School of Health Sciences, Purdue University, West Lafayette, IN 47907-2051, USA
| | - João B. T. Rocha
- Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Santa Maria 97105-900, RS, Brazil
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
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Zhu Q, Bai X, Li Q, Zhang M, Hu G, Pan K, Liu H, Ke Z, Hong Q, Qiu J. PcaR, a GntR/FadR Family Transcriptional Repressor Controls the Transcription of Phenazine-1-Carboxylic Acid 1,2-Dioxygenase Gene Cluster in Sphingomonas histidinilytica DS-9. Appl Environ Microbiol 2023; 89:e0212122. [PMID: 37191535 PMCID: PMC10304782 DOI: 10.1128/aem.02121-22] [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: 12/16/2022] [Accepted: 04/29/2023] [Indexed: 05/17/2023] Open
Abstract
In our previous study, the phenazine-1-carboxylic acid (PCA) 1,2-dioxygenase gene cluster (pcaA1A2A3A4 cluster) in Sphingomonas histidinilytica DS-9 was identified to be responsible for the conversion of PCA to 1,2-dihydroxyphenazine (Ren Y, Zhang M, Gao S, Zhu Q, et al. 2022. Appl Environ Microbiol 88:e00543-22). However, the regulatory mechanism of the pcaA1A2A3A4 cluster has not been elucidated yet. In this study, the pcaA1A2A3A4 cluster was found to be transcribed as two divergent operons: pcaA3-ORF5205 (named A3-5205 operon) and pcaA1A2-ORF5208-pcaA4-ORF5210 (named A1-5210 operon). The promoter regions of the two operons were overlapped. PcaR acts as a transcriptional repressor of the pcaA1A2A3A4 cluster, and it belongs to GntR/FadR family transcriptional regulator. Gene disruption of pcaR can shorten the lag phase of PCA degradation. The results of electrophoretic mobility shift assay and DNase I footprinting showed that PcaR binds to a 25-bp motif in the ORF5205-pcaA1 intergenic promoter region to regulate the expression of two operons. The 25-bp motif covers the -10 region of the promoter of A3-5205 operon and the -35 region and -10 region of the promoter of A1-5210 operon. The TNGT/ANCNA box within the motif was essential for PcaR binding to the two promoters. PCA acted as an effector of PcaR, preventing it from binding to the promoter region and repressing the transcription of the pcaA1A2A3A4 cluster. In addition, PcaR represses its own transcription, and this repression can be relieved by PCA. This study reveals the regulatory mechanism of PCA degradation in strain DS-9, and the identification of PcaR increases the variety of regulatory model of the GntR/FadR-type regulator. IMPORTANCE Sphingomonas histidinilytica DS-9 is a phenazine-1-carboxylic acid (PCA)-degrading strain. The 1,2-dioxygenase gene cluster (pcaA1A2A3A4 cluster, encoding dioxygenase PcaA1A2, reductase PcaA3, and ferredoxin PcaA4) is responsible for the initial degradation step of PCA and widely distributed in Sphingomonads, but its regulatory mechanism has not been investigated yet. In this study, a GntR/FadR-type transcriptional regulator PcaR repressing the transcription of pcaA1A2A3A4 cluster and pcaR gene was identified and characterized. The binding site of PcaR in ORF5205-pcaA1 intergenic promoter region contains a TNGT/ANCNA box, which is important for the binding. These findings enhance our understanding of the molecular mechanism of PCA degradation.
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Affiliation(s)
- Qian Zhu
- Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Xuekun Bai
- Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Qian Li
- Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Mingliang Zhang
- Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Gang Hu
- Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Kaihua Pan
- Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Hongfei Liu
- Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Zhijian Ke
- School of Biological and Chemical Engineering, Ningbo Tech University, Ningbo, Zhejiang, People’s Republic of China
| | - Qing Hong
- Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
| | - Jiguo Qiu
- Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, People’s Republic of China
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9
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Li Y, Li P, Zhang W, Zheng X, Gu Q. New Wine in Old Bottle: Caenorhabditis Elegans in Food Science. FOOD REVIEWS INTERNATIONAL 2023. [DOI: 10.1080/87559129.2023.2172429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Affiliation(s)
- Yonglu Li
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, People’s Republic of China
| | - Ping Li
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, People’s Republic of China
| | - Weixi Zhang
- Department of Food Science and Nutrition; Zhejiang Key Laboratory for Agro-food Processing; Fuli Institute of Food Science; National Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou, People’s Republic of China
| | - Xiaodong Zheng
- Department of Food Science and Nutrition; Zhejiang Key Laboratory for Agro-food Processing; Fuli Institute of Food Science; National Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou, People’s Republic of China
| | - Qing Gu
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, People’s Republic of China
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Long T, Tang Y, He YN, He CL, Chen X, Guo MS, Wu JM, Yu L, Yu CL, Law BYK, Qin DL, Wu AG, Zhou XG. Citri Reticulatae Semen extract promotes healthy aging and neuroprotection via autophagy induction in Caenorhabditis elegans. J Gerontol A Biol Sci Med Sci 2022; 77:2186-2194. [PMID: 35788666 DOI: 10.1093/gerona/glac136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Indexed: 01/18/2023] Open
Abstract
Nutrition intervention has emerged as a potential strategy to delay aging and promote healthy longevity. Citri Reticulatae Semen (CRS) has diverse beneficial effects and has been used for thousands of years to treat pain. However, the health benefits of CRS in prolonging healthspan and improving aging-related diseases and the exact mechanisms remain poorly characterized. In this study, Caenorhabditis elegans (C. elegans) was used as a model organism to study the anti-aging and healthspan promoting activities of 75% ethanol extract of CRS (CRSE). The results showed that treatment with CRSE at 1000 μg/mL significantly extended the lifespan of worms by 18.93% without detriment to healthspan and fitness, as evidenced by the delayed aging-related phenotypes and increased body length and width and reproductive output. In addition, CRSE treatment enhanced the ability of resistance under heat, oxidative, and pathogenic bacterial stress. Consistently, heat shock proteins and antioxidant enzyme-related and pathogenesis-related (PR) genes were up-regulated by CRSE treatment. Furthermore, CRSE supplementation also improved α-synuclein, 6-OHDA, and polyQ40-induced pathologies in transgenic C. elegans models of Parkinson's disease (PD) and Huntington's disease (HD). The mechanistic study demonstrated that CRSE induced autophagy in worms, while the RNAi knockdown of 4 key autophagy-related genes including lgg-1, bec-1, vps-34, and unc-51 remarkably abrogated the beneficial effects of CRSE on the extending of lifespan and healthspan and neuroprotection, demonstrating that CRSE exerts beneficial effects via autophagy induction in worms. Together, our current findings provide new insights into the practical application of CRS for the prevention of aging and aging-related diseases.
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Affiliation(s)
- Tao Long
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China.,Central Nervous System Drug Key Laboratory of Sichuan Province, Luzhou, Sichuan, China
| | - Yong Tang
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China.,State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau, China
| | - Yan-Ni He
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China.,Central Nervous System Drug Key Laboratory of Sichuan Province, Luzhou, Sichuan, China
| | - Chang-Long He
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China.,Central Nervous System Drug Key Laboratory of Sichuan Province, Luzhou, Sichuan, China
| | - Xue Chen
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China.,Central Nervous System Drug Key Laboratory of Sichuan Province, Luzhou, Sichuan, China
| | - Min-Song Guo
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China
| | - Jian-Ming Wu
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China
| | - Lu Yu
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China
| | - Chong-Lin Yu
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China
| | - Betty Yuen-Kwan Law
- State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau, China
| | - Da-Lian Qin
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China
| | - An-Guo Wu
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China
| | - Xiao-Gang Zhou
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China.,Central Nervous System Drug Key Laboratory of Sichuan Province, Luzhou, Sichuan, China
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11
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Evaluation of Blood-Brain-Barrier Permeability, Neurotoxicity, and Potential Cognitive Impairment by Pseudomonas aeruginosa’s Virulence Factor Pyocyanin. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:3060579. [PMID: 35340215 PMCID: PMC8948603 DOI: 10.1155/2022/3060579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 12/07/2021] [Accepted: 01/13/2022] [Indexed: 12/04/2022]
Abstract
Pyocyanin (PCN) is a redox-active secondary metabolite produced by Pseudomonas aeruginosa as its primary virulence factor. Several studies have reported the cytotoxic potential of PCN and its role during infection establishment and progression. Considering its ability to diffuse through biological membranes, it is hypothesized that PCN can gain entry into the brain and induce oxidative stress across the blood-brain barrier (BBB), ultimately contributing towards reactive oxygen species (ROS) mediated neurodegeneration. Potential roles of PCN in the central nervous system (CNS) have never been evaluated, hence the study aimed to evaluate PCN's probable penetration into CNS through blood-brain barrier (BBB) using both in silico and in vivo (Balb/c mice) approaches and the impact of ROS generation via commonly used tests: Morris water maze test, novel object recognition, elevated plus maze test, and tail suspension test. Furthermore, evidence for ROS generation in the brain was assessed using glutathione S-transferase assay. PCN demonstrated BBB permeability albeit in minute quantities. A significant hike was observed in ROS generation (P < 0.0001) along with changes in behavior indicating PCN permeability across BBB and potentially affecting cognitive functions. This is the first study exploring the potential role of PCN in influencing the cognitive functions of test animals.
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12
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Ali M, Gu T, Yu X, Bashir A, Wang Z, Sun X, Ashraf NM, Li L. Identification of the Genes of the Plant Pathogen Pseudomonas syringae MB03 Required for the Nematicidal Activity Against Caenorhabditis elegans Through an Integrated Approach. Front Microbiol 2022; 13:826962. [PMID: 35356513 PMCID: PMC8959697 DOI: 10.3389/fmicb.2022.826962] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 02/11/2022] [Indexed: 01/04/2023] Open
Abstract
Nematicidal potential of the common plant pathogen Pseudomonas syringae has been recently identified against Caenorhabditis elegans. The current study was designed to investigate the detailed genetic mechanism of the bacterial pathogenicity by applying comparative genomics, transcriptomics, mutant library screening, and protein expression. Results showed that P. syringae strain MB03 could kill C. elegans in the liquid assay by gut colonization. The genome of P. syringae MB03 was sequenced and comparative analysis including multi locus sequence typing, and genome-to-genome distance placed MB03 in phylogroup II of P. syringae. Furthermore, comparative genomics of MB03 with nematicidal strains of Pseudomonas aeruginosa (PAO1 and PA14) predicted 115 potential virulence factors in MB03. However, genes for previously reported nematicidal metabolites, such as phenazine, pyochelin, and pyrrolnitrin, were found absent in the MB03 genome. Transcriptomics analysis showed that the growth phase of the pathogen considerably affected the expression of virulence factors, as genes for the flagellum, glutamate ABC transporter, phoP/phoQ, fleS/fleR, type VI secretion system, and serralysin were highly up-regulated when stationary phase MB03 cells interacted with C. elegans. Additionally, screening of a transposon insertion mutant library led to the identification of other nematicidal genes such as acnA, gltP, oprD, and zapE. Finally, the nematicidal activity of selected proteins was confirmed by heterologous expression in Escherichia coli.
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Affiliation(s)
- Muhammad Ali
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
- Department of Biotechnology, COMSATS University Islamabad, Abbottabad, Pakistan
| | - Tong Gu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Xun Yu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Anum Bashir
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Zhiyong Wang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Xiaowen Sun
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Naeem Mahmood Ashraf
- Department of Biochemistry and Biotechnology, University of Gujrat, Gujrat, Pakistan
| | - Lin Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
- *Correspondence: Lin Li,
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13
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Reddy Gajjala RK, Gade PS, Bhatt P, Vishwakarma N, Singh S. Enzyme decorated dendritic bimetallic nanocomposite biosensor for detection of HCHO. Talanta 2022; 238:123054. [PMID: 34801910 DOI: 10.1016/j.talanta.2021.123054] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 09/20/2021] [Accepted: 11/07/2021] [Indexed: 01/23/2023]
Abstract
In recent times, bi- and tri-metallic nanocomposites are being extensively studied to improve the catalytic surface and sensitivity of detection. In this study, we designed a formaldehyde dehydrogenase decorated Cys-AuPd-ErGO nanocomposite with fern like AuPd dendrites deposited on reduced graphene oxide (ErGO) on screen printed electrode (SPE) for determination of NADH and successfully demonstrated its application for detection of HCHO. This biosensor exhibited direct electron transfer by lowering the oxidation potential of NADH from +0.63 V to 0.32 V vs Ag/AgCl, avoiding usage of electron mediators. The sensor LOD was 0.3 μM HCHO with excellent sensitivity of 70 μA/μM/cm2 and linear detection range between 1 μM and 100 μM during chronoamperometric studies at applied over potential of +0.35 V vs Ag/AgCl. The sensor was tested for its performance in simulated HCHO adulterated samples of fish and milk, and appreciable recoveries (88-104%) at tested concentrations indicated good sensor performance. It was also validated against conventional method of HPLC with highly acceptable correlation coefficient of 0.99, indicating successful fabrication of a simple, "on site" disposable sensor for HCHO detection. The developed biosensor can also find wide application in quantitative measurement of NADH and analytes involved in reactions with the co-enzyme.
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Affiliation(s)
- Rajendra Kumar Reddy Gajjala
- Microbiology & Fermentation Technology Department, CSIR-Central Food Technological Research Institute (CFTRI), Mysuru, 570020, India
| | - Pravin Savata Gade
- Microbiology & Fermentation Technology Department, CSIR-Central Food Technological Research Institute (CFTRI), Mysuru, 570020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, UP, 201002, India
| | - Praveena Bhatt
- Microbiology & Fermentation Technology Department, CSIR-Central Food Technological Research Institute (CFTRI), Mysuru, 570020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, UP, 201002, India.
| | - Neelam Vishwakarma
- Agrionics- Post Harvest Technologies, CSIR- Central Scientific Instruments Organization (CSIO), Chandigarh, India, 160030; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, UP, 201002, India
| | - Suman Singh
- Agrionics- Post Harvest Technologies, CSIR- Central Scientific Instruments Organization (CSIO), Chandigarh, India, 160030; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, UP, 201002, India
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14
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Proteomic analysis of Caenorhabditis elegans against Salmonella Typhi toxic proteins. Genes Immun 2021; 22:75-92. [PMID: 33986511 DOI: 10.1038/s41435-021-00132-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 04/08/2021] [Accepted: 04/26/2021] [Indexed: 02/03/2023]
Abstract
Bacterial effector molecules are crucial infectious agents that can cause pathogenesis. In the present study, the pathogenesis of toxic Salmonella enterica serovar Typhi (S. Typhi) proteins on the model host Caenorhabditis elegans was investigated by exploring the host's regulatory proteins during infection through the quantitative proteomics approach. Extracted host proteins were analyzed using two-dimensional gel electrophoresis (2D-GE) and differentially regulated proteins were identified using MALDI TOF/TOF/MS analysis. Of the 150 regulated proteins identified, 95 were downregulated while 55 were upregulated. The interaction network of regulated proteins was predicted using the STRING tool. Most downregulated proteins were involved in muscle contraction, locomotion, energy hydrolysis, lipid synthesis, serine/threonine kinase activity, oxidoreductase activity, and protein unfolding. Upregulated proteins were involved in oxidative stress pathways. Hence, cellular stress generated by S. Typhi proteins in the model host was determined using lipid peroxidation as well as oxidant and antioxidant assays. In addition, candidate proteins identified via extract analysis were validated by western blotting, and the roles of several crucial molecules were analyzed in vivo using transgenic strains (myo-2 and col-19) and mutant (ogt-1) of C. elegans. To the best of our knowledge, this is the first study to report protein regulation in host C. elegans exposed to toxic S. Typhi proteins. It highlights the significance of p38 MAPK and JNK immune pathways.
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15
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Salikin NH, Nappi J, Majzoub ME, Egan S. Combating Parasitic Nematode Infections, Newly Discovered Antinematode Compounds from Marine Epiphytic Bacteria. Microorganisms 2020; 8:E1963. [PMID: 33322253 PMCID: PMC7764037 DOI: 10.3390/microorganisms8121963] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 12/08/2020] [Accepted: 12/08/2020] [Indexed: 02/06/2023] Open
Abstract
Parasitic nematode infections cause debilitating diseases and impede economic productivity. Antinematode chemotherapies are fundamental to modern medicine and are also important for industries including agriculture, aquaculture and animal health. However, the lack of suitable treatments for some diseases and the rise of nematode resistance to many available therapies necessitates the discovery and development of new drugs. Here, marine epiphytic bacteria represent a promising repository of newly discovered antinematode compounds. Epiphytic bacteria are ubiquitous on marine surfaces where they are under constant pressure of grazing by bacterivorous predators (e.g., protozoans and nematodes). Studies have shown that these bacteria have developed defense strategies to prevent grazers by producing toxic bioactive compounds. Although several active metabolites against nematodes have been identified from marine bacteria, drug discovery from marine microorganisms remains underexplored. In this review, we aim to provide further insight into the need and potential for marine epiphytic bacteria to become a new source of antinematode drugs. We discuss current and emerging strategies, including culture-independent high throughput screening and the utilization of Caenorhabditis elegans as a model target organism, which will be required to advance antinematode drug discovery and development from marine microbial sources.
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Affiliation(s)
- Nor Hawani Salikin
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, NSW 2052, Australia; (N.H.S.); (J.N.); (M.E.M.)
- School of Industrial Technology, Universiti Sains Malaysia, USM, 11800 Penang, Malaysia
| | - Jadranka Nappi
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, NSW 2052, Australia; (N.H.S.); (J.N.); (M.E.M.)
| | - Marwan E. Majzoub
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, NSW 2052, Australia; (N.H.S.); (J.N.); (M.E.M.)
| | - Suhelen Egan
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, NSW 2052, Australia; (N.H.S.); (J.N.); (M.E.M.)
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16
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Tahrioui A, Ortiz S, Azuama OC, Bouffartigues E, Benalia N, Tortuel D, Maillot O, Chemat S, Kritsanida M, Feuilloley M, Orange N, Michel S, Lesouhaitier O, Cornelis P, Grougnet R, Boutefnouchet S, Chevalier S. Membrane-Interactive Compounds From Pistacia lentiscus L. Thwart Pseudomonas aeruginosa Virulence. Front Microbiol 2020; 11:1068. [PMID: 32528451 PMCID: PMC7264755 DOI: 10.3389/fmicb.2020.01068] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 04/29/2020] [Indexed: 12/22/2022] Open
Abstract
Pseudomonas aeruginosa is capable to deploy a collection of virulence factors that are not only essential for host infection and persistence, but also to escape from the host immune system and to become more resistant to drug therapies. Thus, developing anti-virulence agents that may directly counteract with specific virulence factors or disturb higher regulatory pathways controlling the production of virulence armories are urgently needed. In this regard, this study reports that Pistacia lentiscus L. fruit cyclohexane extract (PLFE1) thwarts P. aeruginosa virulence by targeting mainly the pyocyanin pigment production by interfering with 4-hydroxy-2-alkylquinolines molecules production. Importantly, the anti-virulence activity of PLFE1 appears to be associated with membrane homeostasis alteration through the modulation of SigX, an extracytoplasmic function sigma factor involved in cell wall stress response. A thorough chemical analysis of PLFE1 allowed us to identify the ginkgolic acid (C17:1) and hydroginkgolic acid (C15:0) as the main bioactive membrane-interactive compounds responsible for the observed increased membrane stiffness and anti-virulence activity against P. aeruginosa. This study delivers a promising perspective for the potential future use of PLFE1 or ginkgolic acid molecules as an adjuvant therapy to fight against P. aeruginosa infections.
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Affiliation(s)
- Ali Tahrioui
- Laboratoire de Microbiologie Signaux et Microenvironnement, LMSM EA4312, Université de Rouen Normandie, Normandie Université, Évreux, France
| | - Sergio Ortiz
- CiTCoM UMR 8038 CNRS, Faculté des Sciences Pharmaceutiques et Biologiques, Équipe Produits Naturels, Analyses et Synthèses (PNAS), Université Paris Descartes, Paris, France
| | - Onyedikachi Cecil Azuama
- Laboratoire de Microbiologie Signaux et Microenvironnement, LMSM EA4312, Université de Rouen Normandie, Normandie Université, Évreux, France
| | - Emeline Bouffartigues
- Laboratoire de Microbiologie Signaux et Microenvironnement, LMSM EA4312, Université de Rouen Normandie, Normandie Université, Évreux, France
| | - Nabiha Benalia
- CiTCoM UMR 8038 CNRS, Faculté des Sciences Pharmaceutiques et Biologiques, Équipe Produits Naturels, Analyses et Synthèses (PNAS), Université Paris Descartes, Paris, France
| | - Damien Tortuel
- Laboratoire de Microbiologie Signaux et Microenvironnement, LMSM EA4312, Université de Rouen Normandie, Normandie Université, Évreux, France
| | - Olivier Maillot
- Laboratoire de Microbiologie Signaux et Microenvironnement, LMSM EA4312, Université de Rouen Normandie, Normandie Université, Évreux, France
| | - Smain Chemat
- Centre de Recherche Scientifique et Technique en Analyses Physico-Chimiques, CRAPC, Bou Ismaïl, Algeria
| | - Marina Kritsanida
- CiTCoM UMR 8038 CNRS, Faculté des Sciences Pharmaceutiques et Biologiques, Équipe Produits Naturels, Analyses et Synthèses (PNAS), Université Paris Descartes, Paris, France
| | - Marc Feuilloley
- Laboratoire de Microbiologie Signaux et Microenvironnement, LMSM EA4312, Université de Rouen Normandie, Normandie Université, Évreux, France
| | - Nicole Orange
- Laboratoire de Microbiologie Signaux et Microenvironnement, LMSM EA4312, Université de Rouen Normandie, Normandie Université, Évreux, France
| | - Sylvie Michel
- CiTCoM UMR 8038 CNRS, Faculté des Sciences Pharmaceutiques et Biologiques, Équipe Produits Naturels, Analyses et Synthèses (PNAS), Université Paris Descartes, Paris, France
| | - Olivier Lesouhaitier
- Laboratoire de Microbiologie Signaux et Microenvironnement, LMSM EA4312, Université de Rouen Normandie, Normandie Université, Évreux, France
| | - Pierre Cornelis
- Laboratoire de Microbiologie Signaux et Microenvironnement, LMSM EA4312, Université de Rouen Normandie, Normandie Université, Évreux, France
| | - Raphaël Grougnet
- CiTCoM UMR 8038 CNRS, Faculté des Sciences Pharmaceutiques et Biologiques, Équipe Produits Naturels, Analyses et Synthèses (PNAS), Université Paris Descartes, Paris, France
| | - Sabrina Boutefnouchet
- CiTCoM UMR 8038 CNRS, Faculté des Sciences Pharmaceutiques et Biologiques, Équipe Produits Naturels, Analyses et Synthèses (PNAS), Université Paris Descartes, Paris, France
| | - Sylvie Chevalier
- Laboratoire de Microbiologie Signaux et Microenvironnement, LMSM EA4312, Université de Rouen Normandie, Normandie Université, Évreux, France
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Dervisevic E, Tuck KL, Voelcker NH, Cadarso VJ. Recent Progress in Lab-On-a-Chip Systems for the Monitoring of Metabolites for Mammalian and Microbial Cell Research. SENSORS (BASEL, SWITZERLAND) 2019; 19:E5027. [PMID: 31752167 PMCID: PMC6891382 DOI: 10.3390/s19225027] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/13/2019] [Accepted: 11/14/2019] [Indexed: 12/11/2022]
Abstract
Lab-on-a-chip sensing technologies have changed how cell biology research is conducted. This review summarises the progress in the lab-on-a-chip devices implemented for the detection of cellular metabolites. The review is divided into two subsections according to the methods used for the metabolite detection. Each section includes a table which summarises the relevant literature and also elaborates the advantages of, and the challenges faced with that particular method. The review continues with a section discussing the achievements attained due to using lab-on-a-chip devices within the specific context. Finally, a concluding section summarises what is to be resolved and discusses the future perspectives.
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Affiliation(s)
- Esma Dervisevic
- Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia;
| | - Kellie L. Tuck
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia;
| | - Nicolas H. Voelcker
- Monash Institute of Pharmaceutical Sciences (MIPS), Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia;
- Commonwealth Scientific and Industrial Research Organization (CSIRO), Clayton, VIC 3168, Australia
- The Melbourne Centre for Nanofabrication, Australian National Fabrication Facility-Victorian Node, Clayton, VIC 3800, Australia
- Department of Materials Science and Engineering, Monash University, Clayton, VIC 3800, Australia
| | - Victor J. Cadarso
- Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia;
- The Melbourne Centre for Nanofabrication, Australian National Fabrication Facility-Victorian Node, Clayton, VIC 3800, Australia
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18
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Mitochondrial UPR repression during Pseudomonas aeruginosa infection requires the bZIP protein ZIP-3. Proc Natl Acad Sci U S A 2019; 116:6146-6151. [PMID: 30850535 DOI: 10.1073/pnas.1817259116] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Mitochondria generate most cellular energy and are targeted by multiple pathogens during infection. In turn, metazoans employ surveillance mechanisms such as the mitochondrial unfolded protein response (UPRmt) to detect and respond to mitochondrial dysfunction as an indicator of infection. The UPRmt is an adaptive transcriptional program regulated by the transcription factor ATFS-1, which induces genes that promote mitochondrial recovery and innate immunity. The bacterial pathogen Pseudomonas aeruginosa produces toxins that disrupt oxidative phosphorylation (OXPHOS), resulting in UPRmt activation. Here, we demonstrate that Pseudomonas aeruginosa exploits an intrinsic negative regulatory mechanism mediated by the Caenorhabditis elegans bZIP protein ZIP-3 to repress UPRmt activation. Strikingly, worms lacking zip-3 were impervious to Pseudomonas aeruginosa-mediated UPRmt repression and resistant to infection. Pathogen-secreted phenazines perturbed mitochondrial function and were the primary cause of UPRmt activation, consistent with these molecules being electron shuttles and virulence determinants. Surprisingly, Pseudomonas aeruginosa unable to produce phenazines and thus elicit UPRmt activation were hypertoxic in zip-3-deletion worms. These data emphasize the significance of virulence-mediated UPRmt repression and the potency of the UPRmt as an antibacterial response.
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Xu Y, Park Y. Application of Caenorhabditis elegans for Research on Endoplasmic Reticulum Stress. Prev Nutr Food Sci 2018; 23:275-281. [PMID: 30675455 PMCID: PMC6342542 DOI: 10.3746/pnf.2018.23.4.275] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 08/21/2018] [Indexed: 01/01/2023] Open
Abstract
Caenorhabditis elegans is a versatile model organism that has been applied to research involving obesity, aging, and neurodegenerative diseases. C. elegans has many advantages over traditional animal models, including ease of handling, a short lifespan, a fully sequenced genome, ease of genetic manipulation, and a high similarity to human disease-related genes. With established C. elegans models of human disease, C. elegans provides a great platform for studying disease pathologies, including endoplasmic reticulum (ER) stress, which is characterized by the accumulation of unfolded and misfolded proteins involved in the pathologies of many diseases. ER stress can lead to activation of the unfolded and misfolded protein response, a mechanism that attenuates ER stress and recovers ER homeostasis. The current review gives an introduction to C. elegans and ER stress, along with the pathological role of ER stress in disease and the application of worm models in ER stress-related research.
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Affiliation(s)
- Yuejia Xu
- Department of Food Science, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Yeonhwa Park
- Department of Food Science, University of Massachusetts Amherst, Amherst, MA 01003, USA
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20
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Novel Three-Component Phenazine-1-Carboxylic Acid 1,2-Dioxygenase in Sphingomonas wittichii DP58. Appl Environ Microbiol 2017; 83:AEM.00133-17. [PMID: 28188209 DOI: 10.1128/aem.00133-17] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 02/06/2017] [Indexed: 11/20/2022] Open
Abstract
Phenazine-1-carboxylic acid, the main component of shenqinmycin, is widely used in southern China for the prevention of rice sheath blight. However, the fate of phenazine-1-carboxylic acid in soil remains uncertain. Sphingomonas wittichii DP58 can use phenazine-1-carboxylic acid as its sole carbon and nitrogen sources for growth. In this study, dioxygenase-encoding genes, pcaA1A2, were found using transcriptome analysis to be highly upregulated upon phenazine-1-carboxylic acid biodegradation. PcaA1 shares 68% amino acid sequence identity with the large oxygenase subunit of anthranilate 1,2-dioxygenase from Rhodococcus maanshanensis DSM 44675. The dioxygenase was coexpressed in Escherichia coli with its adjacent reductase-encoding gene, pcaA3, and ferredoxin-encoding gene, pcaA4, and showed phenazine-1-carboxylic acid consumption. The dioxygenase-, ferredoxin-, and reductase-encoding genes were expressed in Pseudomonas putida KT2440 or E. coli BL21, and the three recombinant proteins were purified. A phenazine-1-carboxylic acid conversion capability occurred in vitro only when all three components were present. However, P. putida KT2440 transformed with pcaA1A2 obtained phenazine-1-carboxylic acid degradation ability, suggesting that phenazine-1-carboxylic acid 1,2-dioxygenase has low specificities for its ferredoxin and reductase. This was verified by replacing PcaA3 with RedA2 in the in vitro enzyme assay. High-performance liquid chromatography-mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR) analysis showed that phenazine-1-carboxylic acid was converted to 1,2-dihydroxyphenazine through decarboxylation and hydroxylation, indicating that PcaA1A2A3A4 constitutes the initial phenazine-1-carboxylic acid 1,2-dioxygenase. This study fills a gap in our understanding of the biodegradation of phenazine-1-carboxylic acid and illustrates a new dioxygenase for decarboxylation.IMPORTANCE Phenazine-1-carboxylic acid is widely used in southern China as a key fungicide to prevent rice sheath blight. However, the degradation characteristics of phenazine-1-carboxylic acid and the environmental consequences of the long-term application are not clear. S. wittichii DP58 can use phenazine-1-carboxylic acid as its sole carbon and nitrogen sources. In this study, a three-component dioxygenase, PcaA1A2A3A4, was determined to be the initial dioxygenase for phenazine-1-carboxylic acid degradation in S. wittichii DP58. Phenazine-1-carboxylic acid was converted to 1,2-dihydroxyphenazine through decarboxylation and hydroxylation. This finding may help us discover the pathway for phenazine-1-carboxylic acid degradation.
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Guttenberger N, Blankenfeldt W, Breinbauer R. Recent developments in the isolation, biological function, biosynthesis, and synthesis of phenazine natural products. Bioorg Med Chem 2017; 25:6149-6166. [PMID: 28094222 DOI: 10.1016/j.bmc.2017.01.002] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 12/29/2016] [Accepted: 01/04/2017] [Indexed: 12/24/2022]
Abstract
Phenazines are natural products which are produced by bacteria or by archaeal Methanosarcina species. The tricyclic ring system enables redox processes, which producing organisms use for oxidation of NADH or for the generation of reactive oxygen species (ROS), giving them advantages over other microorganisms. In this review we summarize the progress in the field since 2005 regarding the isolation of new phenazine natural products, new insights in their biological function, and particularly the now almost completely understood biosynthesis. The review is complemented by a description of new synthetic methods and total syntheses of phenazines.
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Affiliation(s)
- Nikolaus Guttenberger
- Institute of Organic Chemistry, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria; Institute of Chemistry-Analytical Chemistry, University of Graz, Universitaetsplatz 1, 8010 Graz, Austria
| | - Wulf Blankenfeldt
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstr. 7, 38124 Braunschweig, Germany; Institute for Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig, Spielmannstr. 7, 38106 Braunschweig, Germany
| | - Rolf Breinbauer
- Institute of Organic Chemistry, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria.
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22
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Mossine VV, Waters JK, Chance DL, Mawhinney TP. Transient Proteotoxicity of Bacterial Virulence Factor Pyocyanin in Renal Tubular Epithelial Cells Induces ER-Related Vacuolation and Can Be Efficiently Modulated by Iron Chelators. Toxicol Sci 2016; 154:403-415. [PMID: 27613716 PMCID: PMC5139071 DOI: 10.1093/toxsci/kfw174] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Persistent infections of biofilm forming bacteria, such as Pseudomonas aeruginosa, are common among human populations, due to the bacterial resistance to antibiotics and other adaptation strategies, including release of cytotoxic virulent factors such as pigment pyocyanin (PCN). Urinary tract infections harbor P. aeruginosa strains characterized by the highest PCN-producing capacity, yet no information is available on PCN cytotoxicity mechanism in kidney. We report here that renal tubular epithelial cell (RTEC) line NRK-52E responds to PCN treatments with paraptosis-like activity features. Specifically, PCN-treated cells experienced dilation of endoplasmic reticulum (ER) and an extensive development of ER-derived vacuoles after about 8 h. This process was accompanied with hyper-activation of proteotoxic stress-inducible transcription factors Nrf2, ATF6, and HSF-1. The cells could be rescued by withdrawal of PCN from the culture media before the vacuoles burst and cells die of non-programmed necrosis after about 24–30 h. The paraptosis-like activity was abrogated by co-treatment of the cells with metal-chelating antioxidants. A microscopic examination of cells co-treated with PCN and agents aiming at a variety of the cellular stress mediators and pathways have identified iron as a single most significant co-factor of the PCN cytotoxicity in the RTECs. Among biologically relevant metal ions, low micromolar Fe2+ specifically mediated anaerobic oxidation of glutathione by PCN, but catechol derivatives and other strong iron complexing agents could inhibit the reaction. Our data suggest that iron chelation could be considered as a supplementary treatment in the PCN-positive infections.
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Affiliation(s)
- Valeri V Mossine
- Department of Biochemistry .,Experiment Station Chemical Labs, University of Missouri, Columbia, Missouri 65211
| | - James K Waters
- Experiment Station Chemical Labs, University of Missouri, Columbia, Missouri 65211
| | - Deborah L Chance
- Department of Molecular Microbiology and Immunology.,Department of Child Health, University of Missouri, Columbia, Missouri 65211
| | - Thomas P Mawhinney
- Department of Biochemistry.,Experiment Station Chemical Labs, University of Missouri, Columbia, Missouri 65211.,Department of Child Health, University of Missouri, Columbia, Missouri 65211
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23
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Heine D, Sundaram S, Beudert M, Martin K, Hertweck C. A widespread bacterial phenazine forms S-conjugates with biogenic thiols and crosslinks proteins. Chem Sci 2016; 7:4848-4855. [PMID: 30155132 PMCID: PMC6016718 DOI: 10.1039/c6sc00503a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 04/13/2016] [Indexed: 01/13/2023] Open
Abstract
Phenazines are redox-active compounds produced by a range of bacteria, including many pathogens. Endowed with various biological activities, these ubiquitous N-heterocycles are well known for their ability to generate reactive oxygen species by redox cycling. Phenazines may lead to an irreversible depletion of glutathione, but a detailed mechanism has remained elusive. Furthermore, it is not understood why phenazines have so many protein targets and cause protein misfolding as well as their aggregation. Here we report the discovery of unprecedented conjugates (panphenazines A, B) of panthetheine and phenazine-1-carboxylic (PCA) acid from a Kitasatospora sp., which prompted us to investigate their biogenesis. We found that PCA reacts with diverse biogenic thiols under radical-forming conditions, which provides a plausible model for irreversible glutathione depletion. To evaluate the scope of the reaction in cells we designed biotin and rhodamine conjugates for protein labelling and examined their covalent fusion with model proteins (ketosynthase, carbonic anhydrase III, albumin). Our results reveal important, yet overlooked biological roles of phenazines and show for the first time their function in protein conjugation and crosslinking.
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Affiliation(s)
- D Heine
- Leibniz Institute for Natural Product Research and Infection Biology , Hans Knoell Institute , Beutenbergstrasse 11a , 07745 Jena , Germany .
| | - S Sundaram
- Leibniz Institute for Natural Product Research and Infection Biology , Hans Knoell Institute , Beutenbergstrasse 11a , 07745 Jena , Germany .
| | - Matthias Beudert
- Leibniz Institute for Natural Product Research and Infection Biology , Hans Knoell Institute , Beutenbergstrasse 11a , 07745 Jena , Germany .
| | - K Martin
- Leibniz Institute for Natural Product Research and Infection Biology , Hans Knoell Institute , Beutenbergstrasse 11a , 07745 Jena , Germany .
| | - C Hertweck
- Leibniz Institute for Natural Product Research and Infection Biology , Hans Knoell Institute , Beutenbergstrasse 11a , 07745 Jena , Germany .
- Friedrich Schiller University , 07737 Jena , Germany
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Martinez BA, Kim H, Ray A, Caldwell GA, Caldwell KA. A bacterial metabolite induces glutathione-tractable proteostatic damage, proteasomal disturbances, and PINK1-dependent autophagy in C. elegans. Cell Death Dis 2015; 6:e1908. [PMID: 26469957 PMCID: PMC4632299 DOI: 10.1038/cddis.2015.270] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 08/14/2015] [Accepted: 08/17/2015] [Indexed: 01/14/2023]
Abstract
Gene-by-environment interactions are thought to underlie the majority of idiopathic cases of neurodegenerative disease. Recently, we reported that an environmental metabolite extracted from Streptomyces venezuelae increases ROS and damages mitochondria, leading to eventual neurodegeneration of C. elegans dopaminergic neurons. Here we link those data to idiopathic disease models that predict loss of protein handling as a component of disorder progression. We demonstrate that the bacterial metabolite leads to proteostatic disruption in multiple protein-misfolding models and has the potential to synergistically enhance the toxicity of aggregate-prone proteins. Genetically, this metabolite is epistatically regulated by loss-of-function to pink-1, the C. elegans PARK6 homolog responsible for mitochondrial maintenance and autophagy in other animal systems. In addition, the metabolite works through a genetic pathway analogous to loss-of-function in the ubiquitin proteasome system (UPS), which we find is also epistatically regulated by loss of PINK-1 homeostasis. To determine remitting counter agents, we investigated several established antioxidants and found that glutathione (GSH) can significantly protect against metabolite-induced proteostasis disruption. In addition, GSH protects against the toxicity of MG132 and can compensate for the combined loss of both pink-1 and the E3 ligase pdr-1, a Parkin homolog. In assessing the impact of this metabolite on mitochondrial maintenance, we observe that it causes fragmentation of mitochondria that is attenuated by GSH and an initial surge in PINK-1-dependent autophagy. These studies mechanistically advance our understanding of a putative environmental contributor to neurodegeneration and factors influencing in vivo neurotoxicity.
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Affiliation(s)
- B A Martinez
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA
| | - H Kim
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA
| | - A Ray
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA
| | - G A Caldwell
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA.,Departments of Neurobiology and Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - K A Caldwell
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, USA.,Departments of Neurobiology and Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, USA
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