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Wang C, Ji Y, Huo X, Li X, Lu W, Zhang Z, Dong W, Wang X, Chen H, Tan C. Discovery of Salifungin as a Repurposed Antibiotic against Methicillin-Resistant Staphylococcus aureus with Limited Resistance Development. ACS Infect Dis 2024; 10:1576-1589. [PMID: 38581387 DOI: 10.1021/acsinfecdis.3c00611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2024]
Abstract
Exploring novel antimicrobial drugs and strategies has become essential to the fight MRSA-associated infections. Herein, we found that membrane-disrupted repurposed antibiotic salifungin had excellent bactericidal activity against MRSA, with limited development of drug resistance. Furthermore, adding salifungin effectively decreased the minimum inhibitory concentrations of clinical antibiotics against Staphylococcus aureus. Evaluations of the mechanism demonstrated that salifungin disrupted the level of H+ and K+ ions using hydrophilic and lipophilic groups to interact with bacterial membranes, causing the disruption of bacterial proton motive force followed by impacting on bacterial the function of the respiratory chain and adenosine 5'-triphosphate, thereby inhibiting phosphatidic acid biosynthesis. Moreover, salifungin also significantly inhibited the formation of bacterial biofilms and eliminated established bacterial biofilms by interfering with bacterial membrane potential and inhibiting biofilm-associated gene expression, which was even better than clinical antibiotics. Finally, salifungin exhibited efficacy comparable to or even better than that of vancomycin in the MRSA-infected animal models. In conclusion, these results indicate that salifungin can be a potential drug for treating MRSA-associated infections.
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Affiliation(s)
- Chenchen Wang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430000, Hubei, China
- Hubei Hongshan Laboratory, Wuhan 430000, Hubei, China
| | - Yueyue Ji
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430000, Hubei, China
- Hubei Hongshan Laboratory, Wuhan 430000, Hubei, China
| | - Xingyu Huo
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430000, Hubei, China
- Hubei Hongshan Laboratory, Wuhan 430000, Hubei, China
| | - Xiaodan Li
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430000, Hubei, China
- Hubei Hongshan Laboratory, Wuhan 430000, Hubei, China
| | - Wenjia Lu
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430000, Hubei, China
- Hubei Hongshan Laboratory, Wuhan 430000, Hubei, China
| | - Zhaoran Zhang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430000, Hubei, China
- Hubei Hongshan Laboratory, Wuhan 430000, Hubei, China
| | - Wenqi Dong
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430000, Hubei, China
- Hubei Hongshan Laboratory, Wuhan 430000, Hubei, China
| | - Xiangru Wang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430000, Hubei, China
- Hubei Hongshan Laboratory, Wuhan 430000, Hubei, China
- Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan 430000, Hubei, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan 430000, Hubei, China
- The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430000, Hubei, China
| | - Huanchun Chen
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430000, Hubei, China
- Hubei Hongshan Laboratory, Wuhan 430000, Hubei, China
- Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan 430000, Hubei, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan 430000, Hubei, China
- The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430000, Hubei, China
| | - Chen Tan
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430000, Hubei, China
- Hubei Hongshan Laboratory, Wuhan 430000, Hubei, China
- Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan 430000, Hubei, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan 430000, Hubei, China
- The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430000, Hubei, China
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Wang L, Li W, Li X, Liu J, Chen Y. Antimicrobial Activity and Mechanisms of Walnut Green Husk Extract. Molecules 2023; 28:7981. [PMID: 38138470 PMCID: PMC10745604 DOI: 10.3390/molecules28247981] [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: 11/02/2023] [Revised: 11/28/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
Walnut green husks (WGHs), by-products of walnut production, are believed to possess antimicrobial properties, making them a potential alternative to antibiotics. In this study, the antibacterial activities of three extracts, derived from WGH, against Staphylococcus aureus, Bacillus subtilis, and Escherichia coli were investigated, and the antibacterial mechanisms of an anhydrous ethanol extract of WGH (WGHa) were examined. The results showed that WGHa exhibited inhibitory effects on all tested bacteria. The ultrahigh-performance liquid chromatography-tandem mass spectrometry analysis revealed that the major active compounds present in WGHa were terpenoids, phenols, and flavonoids. Treatment with WGHa resulted in the leakage of intracellular ions and alkaline phosphatase; a reduction in intracellular ATP content, ATPase activity, and nucleic acid content; as well as cellular metabolic viability. The transmission electron microscopy images showed varying degrees of cell deformation and membrane damage following WGHa treatment. The transcriptome sequencing and differentially expressed gene enrichment analyses revealed an up-regulation in pathways associated with RNA degradation, translation, protein export, and oxidative phosphorylation. Conversely, pathways involved in cell movement and localization, as well as cell wall organization and carbohydrate transport, were found to be down-regulated. These findings suggest that WGHa alters cell membrane permeability and causes damage to the cell wall. Additionally, WGHa interferes with cellular energy metabolism, compromises RNA integrity, and induces DNA replication stress, consequently inhibiting the normal growth and proliferation of bacteria. These findings unveiled the antimicrobial mechanisms of WGHa, highlighting its potential application as an antibiotic alternative.
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Affiliation(s)
| | | | | | | | - Yong Chen
- Xinjiang Key Laboratory of Herbivore Nutrition for Meat & Milk, College of Animal Science, Xinjiang Agricultural University, Urumqi 830052, China; (L.W.); (W.L.); (X.L.); (J.L.)
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3
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Bramkamp M, Scheffers DJ. Bacterial membrane dynamics: Compartmentalization and repair. Mol Microbiol 2023; 120:490-501. [PMID: 37243899 DOI: 10.1111/mmi.15077] [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: 03/31/2023] [Revised: 05/08/2023] [Accepted: 05/10/2023] [Indexed: 05/29/2023]
Abstract
In every bacterial cell, the plasma membrane plays a key role in viability as it forms a selective barrier between the inside of the cell and its environment. This barrier function depends on the physical state of the lipid bilayer and the proteins embedded or associated with the bilayer. Over the past decade or so, it has become apparent that many membrane-organizing proteins and principles, which were described in eukaryote systems, are ubiquitous and play important roles in bacterial cells. In this minireview, we focus on the enigmatic roles of bacterial flotillins in membrane compartmentalization and bacterial dynamins and ESCRT-like systems in membrane repair and remodeling.
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Affiliation(s)
- Marc Bramkamp
- Institute for General Microbiology, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Dirk-Jan Scheffers
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, the Netherlands
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Hu X, Xu Y, Liu S, Gudda FO, Ling W, Qin C, Gao Y. Graphene Quantum Dots Nonmonotonically Influence the Horizontal Transfer of Extracellular Antibiotic Resistance Genes via Bacterial Transformation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2301177. [PMID: 37144438 DOI: 10.1002/smll.202301177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 04/10/2023] [Indexed: 05/06/2023]
Abstract
Graphene quantum dots (GQDs) coexist with antibiotic resistance genes (ARGs) in the environment. Whether GQDs influence ARG spread needs investigation, since the resulting development of multidrug-resistant pathogens would threaten human health. This study investigates the effect of GQDs on the horizontal transfer of extracellular ARGs (i.e., transformation, a pivotal way that ARGs spread) mediated by plasmids into competent Escherichia coli cells. GQDs enhance ARG transfer at lower concentrations, which are close to their environmental residual concentrations. However, with further increases in concentration (closer to working concentrations needed for wastewater remediation), the effects of enhancement weaken or even become inhibitory. At lower concentrations, GQDs promote the gene expression related to pore-forming outer membrane proteins and the generation of intracellular reactive oxygen species, thus inducing pore formation and enhancing membrane permeability. GQDs may also act as carriers to transport ARGs into cells. These factors result in enhanced ARG transfer. At higher concentrations, GQD aggregation occurs, and aggregates attach to the cell surface, reducing the effective contact area of recipients for external plasmids. GQDs also form large agglomerates with plasmids and thus hindering ARG entrance. This study could promote the understanding of the GQD-caused ecological risks and benefit their safe application.
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Affiliation(s)
- Xiaojie Hu
- Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - Yanxing Xu
- Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - Si Liu
- Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - Fredrick Owino Gudda
- Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - Wanting Ling
- Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - Chao Qin
- Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - Yanzheng Gao
- Institute of Organic Contaminant Control and Soil Remediation, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
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5
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Zeng X, Hinenoya A, Guan Z, Xu F, Lin J. Critical role of the RpoE stress response pathway in polymyxin resistance of Escherichia coli. J Antimicrob Chemother 2023; 78:732-746. [PMID: 36658759 PMCID: PMC10396327 DOI: 10.1093/jac/dkad003] [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: 11/08/2022] [Accepted: 12/31/2022] [Indexed: 01/21/2023] Open
Abstract
OBJECTIVES Polymyxins, including colistin, are the drugs of last resort to treat MDR bacterial infections in humans. In-depth understanding of the molecular basis and regulation of polymyxin resistance would provide new therapeutic opportunities to combat increasing polymyxin resistance. Here we aimed to identify novel targets that are crucial for polymyxin resistance using Escherichia coli BL21(DE3), a unique colistin-resistant model strain. METHODS BL21(DE3) was subjected to random transposon mutagenesis for screening colistin-susceptible mutants. The insertion sites of desired mutants were mapped; the key genes of interest were also inactivated in different strains to examine functional conservation. Specific genes in the known PmrAB and PhoPQ regulatory network were inactivated to examine crosstalk among different pathways. Lipid A species and membrane phospholipids were analysed by normal phase LC/MS. RESULTS Among eight mutants with increased susceptibility to colistin, five mutants contained different mutations in three genes (rseP, degS and surA) that belong to the RpoE stress response pathway. Inactivation of rpoE, pmrB, eptA or pmrD led to significantly increased susceptibility to colistin; however, inactivation of phoQ or eptB did not change colistin MIC. RpoE mutation in different E. coli and Salmonella resistant strains all led to significant reduction in colistin MIC (16-32-fold). Inactivation of rpoE did not change the lipid A profile but significantly altered the phospholipid profile. CONCLUSIONS Inactivation of the important members of the RpoE regulon in polymyxin-resistant strains led to a drastic reduction in polymyxin MIC and an increase of lysophospholipids with no change in lipid A modifications.
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Affiliation(s)
- Ximin Zeng
- Department of Animal Science, The University of Tennessee, Knoxville, TN, USA
| | - Atsushi Hinenoya
- Department of Animal Science, The University of Tennessee, Knoxville, TN, USA
- Graduate School of Veterinary Science, Osaka Metropolitan University, Osaka, Japan
- Asian Health Science Research Institute, Osaka Metropolitan University, Osaka, Japan
- Osaka International Research Center for Infectious Diseases, Osaka Metropolitan University, Osaka, Japan
| | - Ziqiang Guan
- Department of Biochemistry, Duke University Medical Center, Durham, NC, USA
| | - Fuzhou Xu
- Department of Animal Science, The University of Tennessee, Knoxville, TN, USA
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agriculture and Forestry Sciences, Beijing, China
| | - Jun Lin
- Department of Animal Science, The University of Tennessee, Knoxville, TN, USA
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6
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Cao X, van Putten JPM, Wösten MMSM. Biological functions of bacterial lysophospholipids. Adv Microb Physiol 2023; 82:129-154. [PMID: 36948653 DOI: 10.1016/bs.ampbs.2022.10.001] [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: 11/13/2022]
Abstract
Lysophospholipids (LPLs) are lipid-derived metabolic intermediates in the cell membrane. The biological functions of LPLs are distinct from their corresponding phospholipids. In eukaryotic cells LPLs are important bioactive signaling molecules that regulate many important biological processes, but in bacteria the function of LPLs is still not fully defined. Bacterial LPLs are usually present in cells in very small amounts, but can strongly increase under certain environmental conditions. In addition to their basic function as precursors in membrane lipid metabolism, the formation of distinct LPLs contributes to the proliferation of bacteria under harsh circumstances or may act as signaling molecules in bacterial pathogenesis. This review provides an overview of the current knowledge of the biological functions of bacterial LPLs including lysoPE, lysoPA, lysoPC, lysoPG, lysoPS and lysoPI in bacterial adaptation, survival, and host-microbe interactions.
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Affiliation(s)
- Xuefeng Cao
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Jos P M van Putten
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Marc M S M Wösten
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands.
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7
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de Jonge EF, Vogrinec L, van Boxtel R, Tommassen J. Inactivation of the Mla system and outer-membrane phospholipase A results in disrupted outer-membrane lipid asymmetry and hypervesiculation in Bordetella pertussis. CURRENT RESEARCH IN MICROBIAL SCIENCES 2022; 3:100172. [DOI: 10.1016/j.crmicr.2022.100172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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8
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Tang Z, Chen H, Chen W, Zhong Q, Zhang M, Chen W, Yun YH. Unraveling the antibacterial mechanism of 3-carene against Pseudomonas fragi by integrated proteomics and metabolomics analyses and its application in pork. Int J Food Microbiol 2022; 379:109846. [PMID: 35908494 DOI: 10.1016/j.ijfoodmicro.2022.109846] [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: 01/25/2022] [Revised: 06/11/2022] [Accepted: 07/18/2022] [Indexed: 11/25/2022]
Abstract
Pseudomonas fragi is primarily responsible for the spoilage of various foods, especially meat. The aim of this study was to investigate the antibacterial mechanism of 3-carene against P. fragi. 3-Carene treatment decreased the phospholipid content and the fluidity of the cell membrane, induced reactive oxygen species (ROS) generation and affected respiratory chain dehydrogenase, oxoglutarate dehydrogenase and citrate synthase in P. fragi. Metabolomics and proteomics analyses further showed that in the presence of 3-carene, 519 proteins, 136 metabolites in positive ion mode and 100 metabolites in negative ion mode were differentially expressed. These proteins and metabolites were primarily involved in amino acid metabolism, fatty acid degradation, the tricarboxylic acid cycle (TCA cycle) and other processes. Consequently, the stimulation of 3-carene altered cell membrane properties, disturbed important amino acid and energy metabolism, and even caused oxidative stress. Additionally, the results of total viable counts and the total volatile base nitrogen indicated that 3-carene could significantly improve the preservation of refrigerated pork. This study suggested that 3-carene has promising potential to be developed as a food preservative.
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Affiliation(s)
- Zhiling Tang
- School of Food Sciences & Engineering, Hainan University, 58 People Road, Haikou 570228, PR China
| | - Haiming Chen
- School of Food Sciences & Engineering, Hainan University, 58 People Road, Haikou 570228, PR China
| | - Weijun Chen
- School of Food Sciences & Engineering, Hainan University, 58 People Road, Haikou 570228, PR China
| | - Qiuping Zhong
- School of Food Sciences & Engineering, Hainan University, 58 People Road, Haikou 570228, PR China
| | - Ming Zhang
- School of Food Sciences & Engineering, Hainan University, 58 People Road, Haikou 570228, PR China
| | - Wenxue Chen
- School of Food Sciences & Engineering, Hainan University, 58 People Road, Haikou 570228, PR China.
| | - Yong-Huan Yun
- School of Food Sciences & Engineering, Hainan University, 58 People Road, Haikou 570228, PR China.
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9
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Esmaeilishirazifard E, Usher L, Trim C, Denise H, Sangal V, Tyson GH, Barlow A, Redway KF, Taylor JD, Kremyda-Vlachou M, Davies S, Loftus TD, Lock MMG, Wright K, Dalby A, Snyder LAS, Wuster W, Trim S, Moschos SA. Bacterial Adaptation to Venom in Snakes and Arachnida. Microbiol Spectr 2022; 10:e0240821. [PMID: 35604233 PMCID: PMC9248900 DOI: 10.1128/spectrum.02408-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 04/14/2022] [Indexed: 11/20/2022] Open
Abstract
Animal venoms are considered sterile sources of antimicrobial compounds with strong membrane-disrupting activity against multidrug-resistant bacteria. However, venomous bite wound infections are common in developing nations. Investigating the envenomation organ and venom microbiota of five snake and two spider species, we observed venom community structures that depend on the host venomous animal species and evidenced recovery of viable microorganisms from black-necked spitting cobra (Naja nigricollis) and Indian ornamental tarantula (Poecilotheria regalis) venoms. Among the bacterial isolates recovered from N. nigricollis, we identified two venom-resistant, novel sequence types of Enterococcus faecalis whose genomes feature 16 virulence genes, indicating infectious potential, and 45 additional genes, nearly half of which improve bacterial membrane integrity. Our findings challenge the dogma of venom sterility and indicate an increased primary infection risk in the clinical management of venomous animal bite wounds. IMPORTANCE Notwithstanding their 3 to 5% mortality, the 2.7 million envenomation-related injuries occurring annually-predominantly across Africa, Asia, and Latin America-are also major causes of morbidity. Venom toxin-damaged tissue will develop infections in some 75% of envenomation victims, with E. faecalis being a common culprit of disease; however, such infections are generally considered to be independent of envenomation. Here, we provide evidence on venom microbiota across snakes and arachnida and report on the convergent evolution mechanisms that can facilitate adaptation to black-necked cobra venom in two independent E. faecalis strains, easily misidentified by biochemical diagnostics. Therefore, since inoculation with viable and virulence gene-harboring bacteria can occur during envenomation, acute infection risk management following envenomation is warranted, particularly for immunocompromised and malnourished victims in resource-limited settings. These results shed light on how bacteria evolve for survival in one of the most extreme environments on Earth and how venomous bites must be also treated for infections.
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Affiliation(s)
- Elham Esmaeilishirazifard
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- Westminster Genomic Services, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - Louise Usher
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- Westminster Genomic Services, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - Carol Trim
- School of Psychology and Life Sciences, Faculty of Science, Engineering and Social Sciences, Canterbury Christ Church University, Canterbury, Kent, United Kingdom
| | - Hubert Denise
- EMBL-EBI European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Vartul Sangal
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, Tyne and Wear, United Kingdom
| | - Gregory H. Tyson
- Food and Drug Administration, Center for Veterinary Medicine, Office of Research, Laurel, Maryland, USA
| | - Axel Barlow
- Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Keith F. Redway
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - John D. Taylor
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- Westminster Genomic Services, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- School of Environment and Life Sciences, University of Salford, Salford, Greater Manchester, United Kingdom
| | - Myrto Kremyda-Vlachou
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - Sam Davies
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, Tyne and Wear, United Kingdom
| | | | | | - Kstir Wright
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - Andrew Dalby
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
| | - Lori A. S. Snyder
- School of Life Sciences, Pharmacy, and Chemistry, Kingston University, London, United Kingdom
| | - Wolfgang Wuster
- Molecular Ecology and Evolution at Bangor, School of Biological Sciences, College of Natural Sciences, Bangor University, Bangor, Wales, United Kingdom
| | - Steve Trim
- Venomtech, Ltd., Sandwich, Kent, United Kingdom
| | - Sterghios A. Moschos
- Department of Biomedical Sciences, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- Westminster Genomic Services, Faculty of Science and Technology, University of Westminster, London, United Kingdom
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, Tyne and Wear, United Kingdom
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10
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Jurkowitz MS, Azad AK, Monsma PC, Keiser TL, Kanyo J, Lam TT, Bell CE, Schlesinger LS. Mycobacterium tuberculosis encodes a YhhN family membrane protein with lysoplasmalogenase activity that protects against toxic host lysolipids. J Biol Chem 2022; 298:101849. [PMID: 35314194 PMCID: PMC9052158 DOI: 10.1016/j.jbc.2022.101849] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 03/07/2022] [Accepted: 03/10/2022] [Indexed: 11/09/2022] Open
Abstract
The pathogen Mycobacterium tuberculosis (M.tb) resides in human macrophages, wherein it exploits host lipids for survival. However, little is known about the interaction between M.tb and macrophage plasmalogens, a subclass of glycerophospholipids with a vinyl ether bond at the sn-1 position of the glycerol backbone. Lysoplasmalogens, produced from plasmalogens by hydrolysis at the sn-2 carbon by phospholipase A2, are potentially toxic but can be broken down by host lysoplasmalogenase, an integral membrane protein of the YhhN family that hydrolyzes the vinyl ether bond to release a fatty aldehyde and glycerophospho-ethanolamine or glycerophospho-choline. Curiously, M.tb encodes its own YhhN protein (MtbYhhN), despite having no endogenous plasmalogens. To understand the purpose of this protein, the gene for MtbYhhN (Rv1401) was cloned and expressed in Mycobacterium smegmatis (M.smeg). We found the partially purified protein exhibited abundant lysoplasmalogenase activity specific for lysoplasmenylethanolamine or lysoplasmenylcholine (pLPC) (Vmax∼15.5 μmol/min/mg; Km∼83 μM). Based on cell density, we determined that lysoplasmenylethanolamine, pLPC, lysophosphatidylcholine, and lysophosphatidylethanolamine were not toxic to M.smeg cells, but pLPC and LPC were highly toxic to M.smeg spheroplasts, which are cell wall-deficient mycobacterial forms. Importantly, spheroplasts prepared from M.smeg cells overexpressing MtbYhhN were protected from membrane disruption/lysis by pLPC, which was rapidly depleted from the media. Finally, we found that overexpression of full-length MtbYhhN in M.smeg increased its survival within human macrophages by 2.6-fold compared to vector controls. These data support the hypothesis that MtbYhhN protein confers a growth advantage for mycobacteria in macrophages by cleaving toxic host pLPC into potentially energy-producing products.
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Affiliation(s)
- Marianne S Jurkowitz
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, Ohio, USA.
| | - Abul K Azad
- Host Pathogen Interactions Program, Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Paula C Monsma
- Department of Neuroscience, Ohio State University, Columbus, Ohio, USA
| | - Tracy L Keiser
- Department of Moleculaire Microbiologie, Vrije Universiteit, Amsterdam, the Netherlands
| | - Jean Kanyo
- Keck MS & Proteomics Resource, Yale University, New Haven, Connecticut, USA
| | - TuKiet T Lam
- Keck MS & Proteomics Resource, Yale University, New Haven, Connecticut, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Charles E Bell
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, Ohio, USA; Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, USA
| | - Larry S Schlesinger
- Host Pathogen Interactions Program, Texas Biomedical Research Institute, San Antonio, Texas, USA.
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11
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de Jonge EF, van Boxtel R, Balhuizen MD, Haagsman HP, Tommassen J. Pal depletion results in hypervesiculation and affects cell morphology and outer-membrane lipid asymmetry in bordetellae. Res Microbiol 2022; 173:103937. [DOI: 10.1016/j.resmic.2022.103937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 02/18/2022] [Accepted: 02/21/2022] [Indexed: 10/18/2022]
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12
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Ting SY, LaCourse KD, Ledvina HE, Zhang R, Radey MC, Kulasekara HD, Somavanshi R, Bertolli SK, Gallagher LA, Kim J, Penewit KM, Salipante SJ, Xu L, Peterson SB, Mougous JD. Discovery of coordinately regulated pathways that provide innate protection against interbacterial antagonism. eLife 2022; 11:74658. [PMID: 35175195 PMCID: PMC8926400 DOI: 10.7554/elife.74658] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 02/16/2022] [Indexed: 11/13/2022] Open
Abstract
Bacterial survival is fraught with antagonism, including that deriving from viruses and competing bacterial cells. It is now appreciated that bacteria mount complex antiviral responses; however, whether a coordinated defense against bacterial threats is undertaken is not well understood. Previously, we showed that Pseudomonas aeruginosa possess a danger-sensing pathway that is a critical fitness determinant during competition against other bacteria. Here, we conducted genome-wide screens in P. aeruginosa that reveal three conserved and widespread interbacterial antagonism resistance clusters (arc1-3). We find that although arc1-3 are coordinately activated by the Gac/Rsm danger-sensing system, they function independently and provide idiosyncratic defense capabilities, distinguishing them from general stress response pathways. Our findings demonstrate that Arc3 family proteins provide specific protection against phospholipase toxins by preventing the accumulation of lysophospholipids in a manner distinct from previously characterized membrane repair systems. These findings liken the response of P. aeruginosa to bacterial threats to that of eukaryotic innate immunity, wherein threat detection leads to the activation of specialized defense systems.
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Affiliation(s)
- See-Yeun Ting
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States
| | - Kaitlyn D LaCourse
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States
| | - Hannah E Ledvina
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States
| | - Rutan Zhang
- Department of Medicinal Chemistry, University of Washington School of PharmacySeattleUnited States
| | - Matthew C Radey
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States
| | - Hemantha D Kulasekara
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States
| | - Rahul Somavanshi
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States
| | - Savannah K Bertolli
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States
| | - Larry A Gallagher
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States
| | - Jennifer Kim
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States
| | - Kelsi M Penewit
- Department of Laboratory Medicine and Pathology, University of Washington School of MedicineSeattleUnited States
| | - Stephen J Salipante
- Department of Laboratory Medicine and Pathology, University of Washington School of MedicineSeattleUnited States
| | - Libin Xu
- Department of Medicinal Chemistry, University of Washington School of PharmacySeattleUnited States
| | - S Brook Peterson
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States
| | - Joseph D Mougous
- Department of Microbiology, University of Washington School of MedicineSeattleUnited States,Department of Biochemistry, University of Washington School of MedicineSeattleUnited States,Howard Hughes Medical Institute, University of WashingtonSeattleUnited States
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13
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Pang D, Huang Z, Li Q, Wang E, Liao S, Li E, Zou Y, Wang W. Antibacterial Mechanism of Cinnamaldehyde: Modulation of Biosynthesis of Phosphatidylethanolamine and Phosphatidylglycerol in Staphylococcus aureus and Escherichia coli. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:13628-13636. [PMID: 34739242 DOI: 10.1021/acs.jafc.1c04977] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Cinnamaldehyde is a natural antimicrobial food preservative. Previous studies have suggested that cinnamaldehyde interacts with the cell membrane, but the molecular targets of cinnamaldehyde action on foodborne pathogens are still unclear. In this study, the structural changes of Staphylococcus aureus and Escherichia coli cells were observed after cinnamaldehyde treatment. Then, quantitative real-time polymerase chain reaction (PCR) and parallel reaction monitoring were used for determining the effects of cinnamaldehyde treatment of these bacteria on the expression of genes and proteins associated with glycerophospholipid biosynthesis. Changes in fatty acids (raw materials for the biosynthesis of glycerophospholipids) and glycerophospholipids in S. aureus and E. coli after cinnamaldehyde treatment were analyzed to confirm the results of gene and protein expression experiments. Cinnamaldehyde regulated the glycerophospholipid biosynthesis pathways of these foodborne pathogens, mainly targeting phosphatidylglycerol and phosphatidylethanolamine, which resulted in the disruption of cell membrane integrity.
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Affiliation(s)
- Daorui Pang
- Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangzhou 510610, Guangdong, China
| | - Zhaoxiang Huang
- Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangzhou 510610, Guangdong, China
| | - Qian Li
- Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangzhou 510610, Guangdong, China
| | - Erpei Wang
- Center for Autoimmunity and Inflammation, La Jolla Institute for Immunology, La Jolla 92037, California, United States
| | - Sentai Liao
- Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangzhou 510610, Guangdong, China
| | - Erna Li
- Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangzhou 510610, Guangdong, China
| | - Yuxiao Zou
- Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangzhou 510610, Guangdong, China
| | - Weifei Wang
- Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangzhou 510610, Guangdong, China
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14
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Kleetz J, Vasilopoulos G, Czolkoss S, Aktas M, Narberhaus F. Recombinant and endogenous ways to produce methylated phospholipids in Escherichia coli. Appl Microbiol Biotechnol 2021; 105:8837-8851. [PMID: 34709431 PMCID: PMC8590670 DOI: 10.1007/s00253-021-11654-8] [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: 08/04/2021] [Revised: 10/15/2021] [Accepted: 10/19/2021] [Indexed: 10/31/2022]
Abstract
Escherichia coli is the daily workhorse in molecular biology research labs and an important platform microorganism in white biotechnology. Its cytoplasmic membrane is primarily composed of the phospholipids phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and cardiolipin (CL). As in most other bacteria, the typical eukaryotic phosphatidylcholine (PC) is not a regular component of the E. coli membrane. PC is known to act as a substrate in various metabolic or catabolic reactions, to affect protein folding and membrane insertion, and to activate proteins that originate from eukaryotic environments. Options to manipulate the E. coli membrane to include non-native lipids such as PC might make it an even more powerful and versatile tool for biotechnology and protein biochemistry. This article outlines different strategies how E. coli can be engineered to produce PC and other methylated PE derivatives. Several of these approaches rely on the ectopic expression of genes from natural PC-producing organisms. These include PC synthases, lysolipid acyltransferases, and several phospholipid N-methyltransferases with diverse substrate and product preferences. In addition, we show that E. coli has the capacity to produce PC by its own enzyme repertoire provided that appropriate precursors are supplied. Screening of the E. coli Keio knockout collection revealed the lysophospholipid transporter LplT to be responsible for the uptake of lyso-PC, which is then further acylated to PC by the acyltransferase-acyl carrier protein synthetase Aas. Overall, our study shows that the membrane composition of the most routinely used model bacterium can readily be tailored on demand.Key points• Escherichia coli can be engineered to produce non-native methylated PE derivatives.• These lipids can be produced by foreign and endogenous proteins.• Modification of E. coli membrane offers potential for biotechnology and research.
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Affiliation(s)
- Julia Kleetz
- Microbial Biology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Georgios Vasilopoulos
- Microbial Biology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Simon Czolkoss
- Microbial Biology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Meriyem Aktas
- Microbial Biology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Franz Narberhaus
- Microbial Biology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany.
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15
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Czolkoss S, Borgert P, Poppenga T, Hölzl G, Aktas M, Narberhaus F. Synthesis of the unusual lipid bis(monoacylglycero)phosphate in environmental bacteria. Environ Microbiol 2021; 23:6993-7008. [PMID: 34528360 DOI: 10.1111/1462-2920.15777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 01/05/2023]
Abstract
The bacterial membrane is constantly remodelled in response to environmental conditions and the external supply of precursor molecules. Some bacteria are able to acquire exogenous lyso-phospholipids and convert them to the corresponding phospholipids. Here, we report that some soil-dwelling bacteria have alternative options to metabolize lyso-phosphatidylglycerol (L-PG). We find that the plant-pathogen Agrobacterium tumefaciens takes up this mono-acylated phospholipid and converts it to two distinct isoforms of the non-canonical lipid bis(monoacylglycero)phosphate (BMP). Chromatographic separation and quadrupole-time-of-flight MS/MS analysis revealed the presence of two possible BMP stereo configurations acylated at either of the free hydroxyl groups of the glycerol head group. BMP accumulated in the inner membrane and did not visibly alter cell morphology and growth behaviour. The plant-associated bacterium Sinorhizobium meliloti was also able to convert externally provided L-PG to BMP. Other bacteria like Pseudomonas fluorescens and Escherichia coli metabolized L-PG after cell disruption, suggesting that BMP production in the natural habitat relies both on dedicated uptake systems and on head-group acylation enzymes. Overall, our study adds two previously overlooked phospholipids to the repertoire of bacterial membrane lipids and provides evidence for the remarkable condition-responsive adaptation of bacterial membranes.
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Affiliation(s)
- Simon Czolkoss
- Microbial Biology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Pia Borgert
- Microbial Biology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Tessa Poppenga
- Microbial Biology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Georg Hölzl
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Karlrobert-Kreiten-Straße 13, 53115 Bonn, Germany
| | - Meriyem Aktas
- Microbial Biology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Franz Narberhaus
- Microbial Biology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
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16
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Olatunji S, Bowen K, Huang CY, Weichert D, Singh W, Tikhonova IG, Scanlan EM, Olieric V, Caffrey M. Structural basis of the membrane intramolecular transacylase reaction responsible for lyso-form lipoprotein synthesis. Nat Commun 2021; 12:4254. [PMID: 34253723 PMCID: PMC8275575 DOI: 10.1038/s41467-021-24475-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 06/08/2021] [Indexed: 11/08/2022] Open
Abstract
Lipoproteins serve diverse functions in the bacterial cell and some are essential for survival. Some lipoproteins are adjuvants eliciting responses from the innate immune system of the host. The growing list of membrane enzymes responsible for lipoprotein synthesis includes the recently discovered lipoprotein intramolecular transacylase, Lit. Lit creates a lipoprotein that is less immunogenic, possibly enabling the bacteria to gain a foothold in the host by stealth. Here, we report the crystal structure of the Lit enzyme from Bacillus cereus and describe its mechanism of action. Lit consists of four transmembrane helices with an extracellular cap. Conserved residues map to the cap-membrane interface. They include two catalytic histidines that function to effect unimolecular transacylation. The reaction involves acyl transfer from the sn-2 position of the glyceryl moiety to the amino group on the N-terminal cysteine of the substrate via an 8-membered ring intermediate. Transacylation takes place in a confined aromatic residue-rich environment that likely evolved to bring distant moieties on the substrate into proximity and proper orientation for catalysis.
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Affiliation(s)
- Samir Olatunji
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland
| | - Katherine Bowen
- School of Chemistry, Trinity College Dublin, Dublin, Ireland
| | - Chia-Ying Huang
- Swiss Light Source, Paul Scherrer Institute, Villigen, Switzerland
| | - Dietmar Weichert
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland
| | - Warispreet Singh
- School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom
- Hub for Biotechnology in Build Environment, Newcastle upon Tyne, United Kingdom
| | - Irina G Tikhonova
- School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Eoin M Scanlan
- School of Chemistry, Trinity College Dublin, Dublin, Ireland
| | - Vincent Olieric
- Swiss Light Source, Paul Scherrer Institute, Villigen, Switzerland
| | - Martin Caffrey
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland.
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17
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Method for Specific Identification of the Emerging Zoonotic Pathogen Vibrio vulnificus Lineage 3 (Formerly Biotype 3). J Clin Microbiol 2021; 59:JCM.01763-20. [PMID: 33148703 DOI: 10.1128/jcm.01763-20] [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: 07/16/2020] [Accepted: 10/19/2020] [Indexed: 11/20/2022] Open
Abstract
Vibrio vulnificus is a zoonotic pathogen that is spreading worldwide due to global warming. Lineage 3 (L3; formerly biotype 3) includes the strains of the species with the unique ability to cause fish farm-linked outbreaks of septicemia. The L3 strains emerged recently and are particularly virulent and difficult to identify. Here, we describe a newly developed PCR method based on a comparative genomic study useful for both rapid identification and epidemiological studies of this interesting emerging group. The comparative genomic analysis also revealed the presence of a genetic duplication in the L3 strains that could be related to the unique ability of this lineage to produce septicemia outbreaks.
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18
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McKernan P, Cassidy B, Woodward A, Battiste J, Drevets D, Harrison R. Anionic phospholipid expression as a molecular target in Listeria monocytogenes and Escherichia coli. Int J Antimicrob Agents 2020; 56:106183. [PMID: 33045345 DOI: 10.1016/j.ijantimicag.2020.106183] [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: 04/15/2020] [Revised: 07/02/2020] [Accepted: 10/04/2020] [Indexed: 10/23/2022]
Abstract
This study validates bacterial anionic phospholipids (APs) as a putative molecular target in a novel antibiotic treatment against the Gram-positive bacterium Listeria monocytogenes and the Gram-negative bacterium Escherichia coli. Bacterial AP expression was targeted with its associated protein-ligand partner, annexin A5 (ANXA5). This protein was functionalised with the covalent addition of the antibiotic ampicillin (AMP) and separately with the antibiotic moxifloxacin (MOX). Functionalised ANXA5 serves as a delivery vehicle, directing the antibiotic to bacterial AP expression. The results presented here suggest that this ANXA5-AMP bioconjugate participates in a positive feedback loop where APs, the target of the delivery vehicle ANXA5, are upregulated by the chemotherapeutic payload of the bioconjugate. Importantly, the ANXA5 delivery vehicle is non-toxic to bacterial cells by itself and neither is the ANXA5-antibiotic bioconjugate toxic to human vascular endothelial cells. As measured by the IC50, conjugation to ANXA5 resulted in increasing the antibiotic activity of AMP against L. monocytogenes and E. coli by more than 4 and 3 orders of magnitude, respectively, compared with free AMP, whilst the activity of MOX against L. monocytogenes is increased by 4 orders of magnitude. Given the conservation of AP expression in pathologies such as oncogenesis and other bacterial/viral/parasitic infections, we hypothesise that a therapeutic modality targeting AP expression may be a viable chemotherapeutic strategy in many infectious diseases.
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Affiliation(s)
- Patrick McKernan
- Department of Neurology, University of Oklahoma Health Sciences Center, 865 Research Parkway, Oklahoma City, OK 73104, USA; Department of Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Radiation Oncology, University of Oklahoma Health Sciences Center Oklahoma City, OK, USA
| | - Benjamin Cassidy
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Alexis Woodward
- School of Biomedical Engineering, University of Oklahoma, 202 W. Boyd St., Norman, OK 73019, USA
| | - James Battiste
- Department of Neurology, University of Oklahoma Health Sciences Center, 865 Research Parkway, Oklahoma City, OK 73104, USA; Stephenson Cancer Center, 800 NE 10th St., Oklahoma City, OK 73104, USA
| | - Douglas Drevets
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Medical Services, Department of Veterans Affairs Medical Center, 921 NE 13th St., Oklahoma City, OK 73104, USA
| | - Roger Harrison
- Stephenson Cancer Center, 800 NE 10th St., Oklahoma City, OK 73104, USA; School of Chemical, Biological and Materials Engineering, University of Oklahoma, 100 E. Boyd St., Norman, OK 73019, USA.
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19
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A transcriptome analysis of the antibacterial mechanism of flavonoids from Sedum aizoon L. against Shewanella putrefaciens. World J Microbiol Biotechnol 2020; 36:94. [PMID: 32562062 DOI: 10.1007/s11274-020-02871-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 06/13/2020] [Indexed: 02/06/2023]
Abstract
Flavonoids from Sedum aizoon L. (FSAL) possess prominent antibacterial activity against Shewanella putrefaciens isolated from sea food. In the current study, the involved molecular mechanisms were investigated using transcriptome analyses combined with bioinformatics analysis in vitro for the first time. Results showed that treatment of FSAL (1.0 MIC) damaged the permeability and integrity of cell membrane and induced 721 differentially expressed genes (DEGs) in tested bacteria at transcriptional levels, including 107 DEGs were up-regulated and 614 DEGs were down-regulated. In addition, the RNA-Seq analysis revealed that the majority of DEGs mainly involved in pathways of lipopolysaccharide biosynthesis, glycerophospholipid metabolism, biosynthesis of amino acids, purine metabolism, ABC transporters and response to stimulus. In summary, the integrated results indicated that the intervention of FSAL induced destruction of cell wall and membrane, disorder of the metabolic process and redox balance, and damage of nucleic acids in S. putrefaciens, at last resulted in the death of cells. This study provided new insights into the anti- S. putrefaciens molecular mechanism underlying the treatment of FSAL, which may be served as the basis guide for identifying potential antimicrobial targets and application of FSAL in food safety.
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20
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Nilsson I, Lee SY, Sawyer WS, Baxter Rath CM, Lapointe G, Six DA. Metabolic phospholipid labeling of intact bacteria enables a fluorescence assay that detects compromised outer membranes. J Lipid Res 2020; 61:870-883. [PMID: 32156718 PMCID: PMC7269758 DOI: 10.1194/jlr.ra120000654] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 03/03/2020] [Indexed: 01/09/2023] Open
Abstract
Gram-negative bacteria possess an asymmetric outer membrane (OM) composed primarily of lipopolysaccharides (LPSs) on the outer leaflet and phospholipids (PLs) on the inner leaflet. The loss of this asymmetry due to mutations in the LPS biosynthesis or transport pathways causes the externalization of PLs to the outer leaflet of the OM and leads to OM permeability defects. Here, we used metabolic labeling to detect a compromised OM in intact bacteria. Phosphatidylcholine synthase expression in Escherichia coli allowed for the incorporation of exogenous propargylcholine into phosphatidyl(propargyl)choline and exogenous 1-azidoethyl-choline (AECho) into phosphatidyl(azidoethyl)choline (AEPC), as confirmed by LC/MS analyses. A fluorescent copper-free click reagent poorly labeled AEPC in intact wild-type cells but readily labeled AEPC from lysed cells. Fluorescence microscopy and flow cytometry analyses confirmed the absence of significant AEPC labeling from intact wild-type E. coli strains and revealed significant AEPC labeling in an E. coli LPS transport mutant (lptD4213) and an LPS biosynthesis mutant (E. coli lpxC101). Our results suggest that metabolic PL labeling with AECho is a promising tool for detecting a compromised bacterial OM, revealing aberrant PL externalization, and identifying or characterizing novel cell-active inhibitors of LPS biosynthesis or transport.
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Affiliation(s)
- Inga Nilsson
- Infectious Diseases Area Novartis Institutes for BioMedical Research, Emeryville, CA; Global Discovery Chemistry Novartis Institutes for BioMedical Research, Emeryville, CA
| | - Sheng Y Lee
- Infectious Diseases Area Novartis Institutes for BioMedical Research, Emeryville, CA
| | - William S Sawyer
- Infectious Diseases Area Novartis Institutes for BioMedical Research, Emeryville, CA
| | | | - Guillaume Lapointe
- Global Discovery Chemistry Novartis Institutes for BioMedical Research, Emeryville, CA
| | - David A Six
- Infectious Diseases Area Novartis Institutes for BioMedical Research, Emeryville, CA. mailto:
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21
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Armbruster KM, Komazin G, Meredith TC. Bacterial lyso-form lipoproteins are synthesized via an intramolecular acyl chain migration. J Biol Chem 2020; 295:10195-10211. [PMID: 32471867 DOI: 10.1074/jbc.ra120.014000] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/22/2020] [Indexed: 01/08/2023] Open
Abstract
All bacterial lipoproteins share a variably acylated N-terminal cysteine residue. Gram-negative bacterial lipoproteins are triacylated with a thioether-linked diacylglycerol moiety and an N-acyl chain. The latter is transferred from a membrane phospholipid donor to the α-amino terminus by the enzyme lipoprotein N-acyltransferase (Lnt), using an active-site cysteine thioester covalent intermediate. Many Gram-positive Firmicutes also have N-acylated lipoproteins, but the enzymes catalyzing N-acylation remain uncharacterized. The integral membrane protein Lit (lipoprotein intramolecular transacylase) from the opportunistic nosocomial pathogen Enterococcus faecalis synthesizes a specific lysoform lipoprotein (N-acyl S-monoacylglycerol) chemotype by an unknown mechanism that helps this bacterium evade immune recognition by the Toll-like receptor 2 family complex. Here, we used a deuterium-labeled lipoprotein substrate with reconstituted Lit to investigate intramolecular acyl chain transfer. We observed that Lit transfers the sn-2 ester-linked lipid from the diacylglycerol moiety to the α-amino terminus without forming a covalent thioester intermediate. Utilizing Mut-Seq to analyze an alanine scan library of Lit alleles, we identified two stretches of functionally important amino acid residues containing two conserved histidines. Topology maps based on reporter fusion assays and cysteine accessibility placed both histidines in the extracellular half of the cytoplasmic membrane. We propose a general acid base-promoted catalytic mechanism, invoking direct nucleophilic attack by the substrate α-amino group on the sn-2 ester to form a cyclic tetrahedral intermediate that then collapses to produce lyso-lipoprotein. Lit is a unique example of an intramolecular transacylase differentiated from that catalyzed by Lnt, and provides insight into the heterogeneity of bacterial lipoprotein biosynthetic systems.
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Affiliation(s)
- Krista M Armbruster
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Gloria Komazin
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Timothy C Meredith
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA .,The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park Pennsylvania, USA
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22
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van Hensbergen VP, Wu Y, van Sorge NM, Touqui L. Type IIA Secreted Phospholipase A2 in Host Defense against Bacterial Infections. Trends Immunol 2020; 41:313-326. [PMID: 32151494 DOI: 10.1016/j.it.2020.02.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 02/07/2020] [Accepted: 02/08/2020] [Indexed: 12/13/2022]
Abstract
The enzyme type IIA secreted phospholipase A2 (sPLA2-IIA) is crucial for mammalian innate host defense against bacterial pathogens. Most studies have investigated the role of sPLA2-IIA in systemic bacterial infections, identifying molecular pathways of bacterial resistance against sPLA2-IIA-mediated killing, and providing insight into sPLA2-IIA mechanisms of action. Sensitization of (antibiotic-resistant) bacteria to sPLA2-IIA action by blocking bacterial resistance or by applying sPLA2-IIA to treat bacterial infections might represent a therapeutic option in the future. Because sPLA2-IIA is highly expressed at mucosal barriers, we also discuss how sPLA2-IIA is likely to be an important driver of microbiome composition; we anticipate that future research in this area may bring new insights into the role of sPLA2-IIA in health and disease.
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Affiliation(s)
- Vincent P van Hensbergen
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Yongzheng Wu
- Unité de Biologie Cellulaire de l'infection Microbienne, CNRS UMR3691, Institut Pasteur, Paris, France
| | - Nina M van Sorge
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.
| | - Lhousseine Touqui
- Mucoviscidose et Bronchopathies Chroniques, département Santé Globale; Pasteur Institute, Paris, France.
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23
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Lin Y, Zheng L, Bogdanov M. Measurement of Lysophospholipid Transport Across the Membrane Using Escherichia coli Spheroplasts. Methods Mol Biol 2019; 1949:165-180. [PMID: 30790256 DOI: 10.1007/978-1-4939-9136-5_13] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
In the inner membrane of Gram-negative bacteria lysophospholipid transporter (LplT) and the bifunctional acyl-acyl carrier protein (ACP) synthetase/2-acylglycerolphosphoethanolamine acyltransferase (Aas) form a glycerophospholipid remodeling system, which is capable of facilitating rapid retrograde translocation of lyso forms of phosphatidylethanolamine, phosphatidylglycerol, and cardiolipin across the cytoplasmic membrane. This coupled remodeling enzyme tandem provides an effective method for the measurement of substrate specificity of the lipid regeneration and lysophospholipid transport per se across the membrane. This chapter describes two distinct but complementary methods for the measurement of lysophospholipid transport across membrane using Escherichia coli spheroplasts.
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Affiliation(s)
- Yibin Lin
- Division of Infectious Diseases, Department of Pediatrics, Center for Antimicrobial Resistance and Microbial Genomics, University of Texas Health Science Center at Houston McGovern Medical School, Houston, TX, USA.
| | - Lei Zheng
- Department of Biochemistry and Molecular Biology, Center for Membrane Biology, University of Texas Health Science Center at Houston McGovern Medical School, Houston, TX, USA
| | - Mikhail Bogdanov
- Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston McGovern Medical School, Houston, TX, USA.,Department of Biochemistry and Biotechnology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation
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24
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Shende P, Khair R, Gaud RS. Nanostructured cochleates: a multi-layered platform for cellular transportation of therapeutics. Drug Dev Ind Pharm 2019; 45:869-881. [PMID: 30767577 DOI: 10.1080/03639045.2019.1583757] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Among lipid-based nanocarriers, multi-layered cochleates emerge as a novel delivery system because of prevention of oxidation of hydrophobic and hydrophilic drugs, enhancement in permeability, and reduction in dose of drugs. It also improves oral bioavailability and increases the safety of a drug by targeting at a specific site with less side effects. Nanostructured cochleates are used as a carrier for the delivery of water-insoluble or hydrophobic drugs of anticancer, antiviral and anti-inflammatory action. This review article focuses on different methods for preparation of cochleates, mechanism of formation of cochleates, mechanism of action like cochleate undergoes macrophagic endocytosis and release the drug into the systemic circulation by acting on membrane proteins, phospholipids, and receptors. Advanced methods such as calcium-substituted and β-cyclodextrin-based cochleates, novel techniques include microfluidic and modified trapping method. Cochleates showed enhancement in oral bioavailability of amphotericin B, delivery of factor VII, oral mucosal vaccine adjuvant-delivery system, and delivery of volatile oil. In near future, cochleate will be one of the interesting delivery systems to overcome the stability and encapsulation efficiency issues associated with liposomes. The current limiting factors for commercial preparation of cochleates involve high cost of manufacturing, lack of standardization, and specialized equipments.
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Affiliation(s)
- Pravin Shende
- a Shobhaben Pratapbhai Patel School of Pharmacy and Technology Management , SVKM's NMIMS , Mumbai , India
| | - Rohan Khair
- a Shobhaben Pratapbhai Patel School of Pharmacy and Technology Management , SVKM's NMIMS , Mumbai , India
| | - Ram S Gaud
- a Shobhaben Pratapbhai Patel School of Pharmacy and Technology Management , SVKM's NMIMS , Mumbai , India
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25
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Nandanwar SK, Kim HJ. Anticancer and Antibacterial Activity of Transition Metal Complexes. ChemistrySelect 2019. [DOI: 10.1002/slct.201803073] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Sondavid K. Nandanwar
- Department of Marine Convergence ProgramPukyong National University Busan 48513 Republic of Korea
| | - Hak Jun Kim
- Department of ChemistryPukyong National University Busan 48513 Republic of Korea
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26
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Pang D, Liao S, Wang W, Mu L, Li E, Shen W, Liu F, Zou Y. Destruction of the cell membrane and inhibition of cell phosphatidic acid biosynthesis inStaphylococcus aureus: an explanation for the antibacterial mechanism of morusin. Food Funct 2019; 10:6438-6446. [DOI: 10.1039/c9fo01233h] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Morusin from mulberry inhibits the growth ofS. aureusby destroying its cell membrane and further moderating the phosphatidic acid biosynthesis pathway.
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Affiliation(s)
- Daorui Pang
- Sericultural & Agri-Food Research Institute
- Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods
- Ministry of Agriculture and Rural Affairs
- Guangzhou 510610
- China
| | - Sentai Liao
- Sericultural & Agri-Food Research Institute
- Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods
- Ministry of Agriculture and Rural Affairs
- Guangzhou 510610
- China
| | - Weifei Wang
- Sericultural & Agri-Food Research Institute
- Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods
- Ministry of Agriculture and Rural Affairs
- Guangzhou 510610
- China
| | - Lixia Mu
- Sericultural & Agri-Food Research Institute
- Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods
- Ministry of Agriculture and Rural Affairs
- Guangzhou 510610
- China
| | - Erna Li
- Sericultural & Agri-Food Research Institute
- Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods
- Ministry of Agriculture and Rural Affairs
- Guangzhou 510610
- China
| | - Weizhi Shen
- Sericultural & Agri-Food Research Institute
- Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods
- Ministry of Agriculture and Rural Affairs
- Guangzhou 510610
- China
| | - Fan Liu
- Sericultural & Agri-Food Research Institute
- Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods
- Ministry of Agriculture and Rural Affairs
- Guangzhou 510610
- China
| | - Yuxiao Zou
- Sericultural & Agri-Food Research Institute
- Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Agricultural Products Processing; Key Laboratory of Functional Foods
- Ministry of Agriculture and Rural Affairs
- Guangzhou 510610
- China
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27
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Lin Y, Deepak RNVK, Zheng JZ, Fan H, Zheng L. A dual substrate-accessing mechanism of a major facilitator superfamily protein facilitates lysophospholipid flipping across the cell membrane. J Biol Chem 2018; 293:19919-19931. [PMID: 30373772 DOI: 10.1074/jbc.ra118.005548] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 10/23/2018] [Indexed: 11/06/2022] Open
Abstract
Lysophospholipid transporter (LplT) is a member of the major facilitator superfamily present in many Gram-negative bacteria. LplT catalyzes flipping of lysophospholipids (LPLs) across the bacterial inner membrane, playing an important role in bacterial membrane homeostasis. We previously reported that LplT promotes both uptake of exogenous LPLs and intramembranous LPL flipping across the bilayer. To gain mechanistic insight into this dual LPL-flipping activity, here we implemented a combination of computational approaches and LPL transport analyses to study LPL binding of and translocation by LplT. Our results suggest that LplT translocates LPLs through an elongated cavity exhibiting an extremely asymmetric polarity. We found that two D(E)N motifs form a head group-binding site, in which the carboxylate group of Asp-30 is important for LPL head group recognition. Substitutions of residues in the head group-binding site disrupted both LPL uptake and flipping activities. However, alteration of hydrophobic residues on the interface between the N- and C-terminal domains impaired LPL flipping specifically, resulting in LPLs accumulation in the membrane, but LPL uptake remained active. These results suggest a dual substrate-accessing mechanism, in which LplT recruits LPLs to its substrate-binding site via two routes, either from its extracellular entry or through a membrane-embedded groove between transmembrane helices, and then moves them toward the inner membrane leaflet. This LPL-flipping mechanism is likely conserved in many bacterial species, and our findings illustrate how LplT adjusts the major facilitator superfamily translocation pathway to perform its versatile lipid homeostatic functions.
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Affiliation(s)
- Yibin Lin
- From the Department of Biochemistry and Molecular Biology, Center for Membrane Biology, the University of Texas Health Science Center at Houston McGovern Medical School, Houston Texas 77030
| | - R N V Krishna Deepak
- the Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 138671 Singapore, and
| | - Jonathan Zixiang Zheng
- From the Department of Biochemistry and Molecular Biology, Center for Membrane Biology, the University of Texas Health Science Center at Houston McGovern Medical School, Houston Texas 77030
| | - Hao Fan
- the Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 138671 Singapore, and .,the Department of Biological Sciences (DBS), National University of Singapore, 117558 Singapore, and Center for Computational Biology, DUKE-NUS Medical School, 169857 Singapore
| | - Lei Zheng
- From the Department of Biochemistry and Molecular Biology, Center for Membrane Biology, the University of Texas Health Science Center at Houston McGovern Medical School, Houston Texas 77030,
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Group IIA-Secreted Phospholipase A 2 in Human Serum Kills Commensal but Not Clinical Enterococcus faecium Isolates. Infect Immun 2018; 86:IAI.00180-18. [PMID: 29784864 DOI: 10.1128/iai.00180-18] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 05/18/2018] [Indexed: 11/20/2022] Open
Abstract
Human innate immunity employs cellular and humoral mechanisms to facilitate rapid killing of invading bacteria. The direct killing of bacteria by human serum is attributed mainly to the activity of the complement system, which forms pores in Gram-negative bacteria. Although Gram-positive bacteria are considered resistant to killing by serum, we uncover here that normal human serum effectively kills Enterococcus faecium Comparison of a well-characterized collection of commensal and clinical E. faecium isolates revealed that human serum specifically kills commensal E. faecium strains isolated from normal gut microbiota but not clinical isolates. Inhibitor studies show that the human group IIA secreted phospholipase A2 (hGIIA), but not complement, is responsible for killing of commensal E. faecium strains in human normal serum. This is remarkable since the hGIIA concentration in "noninflamed" serum was considered too low to be bactericidal against Gram-positive bacteria. Mechanistic studies showed that serum hGIIA specifically causes permeabilization of commensal E. faecium membranes. Altogether, we find that a normal concentration of hGIIA in serum effectively kills commensal E. faecium and that resistance of clinical E. faecium to hGIIA could have contributed to the ability of these strains to become opportunistic pathogens in hospitalized patients.
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