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Lau WYV, Taylor PK, Brinkman FSL, Lee AHY. Pathogen-associated gene discovery workflows for novel antivirulence therapeutic development. EBioMedicine 2023; 88:104429. [PMID: 36628845 PMCID: PMC9843249 DOI: 10.1016/j.ebiom.2022.104429] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 11/23/2022] [Accepted: 12/15/2022] [Indexed: 01/11/2023] Open
Abstract
Novel therapeutics to manage bacterial infections are urgently needed as the impact and prevalence of antimicrobial resistance (AMR) grows. Antivirulence therapeutics are an alternative approach to antibiotics that aim to attenuate virulence rather than target bacterial essential functions, while minimizing microbiota perturbation and the risk of AMR development. Beyond known virulence factors, pathogen-associated genes (PAGs; genes found only in pathogens to date) may play an important role in virulence or host association. Many identified PAGs encode uncharacterized hypothetical proteins and represent an untapped wealth of novel drug targets. Here, we review current advances in antivirulence drug research and development, including PAG identification, and provide a comprehensive workflow from the discovery of antivirulence drug targets to drug discovery. We highlight the importance of integrating bioinformatic/genomic-based methods for novel virulence factor discovery, coupled with experimental characterization, into existing drug screening platforms to develop novel and effective antivirulence drugs.
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Affiliation(s)
- Wing Yin Venus Lau
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Patrick K Taylor
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Fiona S L Brinkman
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada.
| | - Amy H Y Lee
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada.
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2
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Rezzoagli C, Granato ET, Kümmerli R. Harnessing bacterial interactions to manage infections: a review on the opportunistic pathogen Pseudomonas aeruginosa as a case example. J Med Microbiol 2020; 69:147-161. [PMID: 31961787 PMCID: PMC7116537 DOI: 10.1099/jmm.0.001134] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
During infections, bacterial pathogens can engage in a variety of interactions with each other, ranging from the cooperative sharing of resources to deadly warfare. This is especially relevant in opportunistic infections, where different strains and species often co-infect the same patient and interact in the host. Here, we review the relevance of these social interactions during opportunistic infections using the human pathogen Pseudomonas aeruginosa as a case example. In particular, we discuss different types of pathogen-pathogen interactions, involving both cooperation and competition, and elaborate on how they impact virulence in multi-strain and multi-species infections. We then review evolutionary dynamics within pathogen populations during chronic infections. We particuarly discuss how local adaptation through niche separation, evolutionary successions and antagonistic co-evolution between pathogens can alter virulence and the damage inflicted on the host. Finally, we outline how studying bacterial social dynamics could be used to manage infections. We show that a deeper appreciation of bacterial evolution and ecology in the clinical context is important for understanding microbial infections and can inspire novel treatment strategies.
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Affiliation(s)
- Chiara Rezzoagli
- Department of Quantitative Biomedicine, University of Zurich, Zurich, Switzerland
| | - Elisa T. Granato
- Department of Zoology, University of Oxford, Oxford, United Kingdom
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Rolf Kümmerli
- Department of Quantitative Biomedicine, University of Zurich, Zurich, Switzerland
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3
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Rezzoagli C, Granato ET, Kümmerli R. In-vivo microscopy reveals the impact of Pseudomonas aeruginosa social interactions on host colonization. ISME JOURNAL 2019; 13:2403-2414. [PMID: 31123320 DOI: 10.1038/s41396-019-0442-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 03/20/2019] [Accepted: 04/24/2019] [Indexed: 12/21/2022]
Abstract
Pathogenic bacteria engage in social interactions to colonize hosts, which include quorum-sensing-mediated communication and the secretion of virulence factors that can be shared as "public goods" between individuals. While in-vitro studies demonstrated that cooperative individuals can be displaced by "cheating" mutants freeriding on social acts, we know less about social interactions in infections. Here, we developed a live imaging system to track virulence factor expression and social strain interactions in the human pathogen Pseudomonas aeruginosa colonizing the gut of Caenorhabditis elegans. We found that shareable siderophores and quorum-sensing systems are expressed during infections, affect host gut colonization, and benefit non-producers. However, non-producers were unable to successfully cheat and outcompete producers. Our results indicate that the limited success of cheats is due to a combination of the down-regulation of virulence factors over the course of the infection, the fact that each virulence factor examined contributed to but was not essential for host colonization, and the potential for negative frequency-dependent selection. Our findings shed new light on bacterial social interactions in infections and reveal potential limits of therapeutic approaches that aim to capitalize on social dynamics between strains for infection control.
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Affiliation(s)
- Chiara Rezzoagli
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland. .,Department of Quantitative Biomedicine, University of Zurich, Zurich, Switzerland.
| | | | - Rolf Kümmerli
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland. .,Department of Quantitative Biomedicine, University of Zurich, Zurich, Switzerland.
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4
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Gao X, Li W, Luo J, Zhang L, Ji J, Zhu X, Wang L, Zhang S, Cui J. Biodiversity of the microbiota in Spodoptera exigua (Lepidoptera: Noctuidae). J Appl Microbiol 2019; 126:1199-1208. [PMID: 30597740 DOI: 10.1111/jam.14190] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/23/2018] [Accepted: 12/27/2018] [Indexed: 02/05/2023]
Abstract
AIMS Spodoptera exigua is a serious pest of many agricultural crops. However, the bacterial communities of S. exigua are poorly studied, particularly over their entire life cycle. We aimed to study the biodiversity of the microbiota across the life cycle of S. exigua and to provide a better and obtain insight into new pest control strategies. METHODS AND RESULTS The bacterial diversity across the life cycle of S. exigua was studied using Illumina MiSeq sequencing of 16S rRNA genes. Spodoptera exigua is dominated by Proteobacteria and Firmicutes, with a total relative abundance of 90·03%. Enterococcus (24·6%), Pseudomonas (12·2%) and Asaia (45·9%) were abundant and active in eggs, while Methylobacterium (18·7%) and Halomonas (16·5%) dominated freshly eclosed larvae. The 3rd and 5th instar larvae were dominated by Enterococcus (76·3 and 62·0%). Pupal stages had the highest microbial diversity. There was no significant difference between newly emerged males and females. Symbionts of eggs were extremely similar and probably vertically transmitted by males during mating. CONCLUSIONS The result showed that the bacterial community was affected by the host developmental stages. Our results also suggest that symbionts of egg mass are probably vertically transmitted control by male spawning adults. SIGNIFICANCE AND IMPACT OF THE STUDY Our study documents the symbiont bacteria across the life cycle of S. exigua. Understanding the microbial symbionts may provide clues to develop potential biocontrol techniques against this pest.
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Affiliation(s)
- X Gao
- State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, PR China
| | - W Li
- State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, PR China
| | - J Luo
- State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, PR China
| | - L Zhang
- State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, PR China
| | - J Ji
- State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, PR China
| | - X Zhu
- State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, PR China
| | - L Wang
- State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, PR China
| | - S Zhang
- State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, PR China
| | - J Cui
- State Key Laboratory of Cotton Biology/Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, Henan, PR China
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5
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Santos LA, Adhikarla H, Yan X, Wang Z, Fouts DE, Vinetz JM, Alcantara LCJ, Hartskeerl RA, Goris MGA, Picardeau M, Reis MG, Townsend JP, Zhao H, Ko AI, Wunder EA. Genomic Comparison Among Global Isolates of L. interrogans Serovars Copenhageni and Icterohaemorrhagiae Identified Natural Genetic Variation Caused by an Indel. Front Cell Infect Microbiol 2018; 8:193. [PMID: 29971217 PMCID: PMC6018220 DOI: 10.3389/fcimb.2018.00193] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/22/2018] [Indexed: 12/30/2022] Open
Abstract
Leptospirosis is a worldwide zoonosis, responsible for more than 1 million cases and 60,000 deaths every year. Among the 13 pathogenic species of the genus Leptospira, serovars belonging to L. interrogans serogroup Icterohaemorrhagiae are considered to be the most virulent strains, and responsible for majority of the reported severe cases. Serovars Copenhageni and Icterohaemorrhagiae are major representatives of this serogroup and despite their public health relevance, little is known regarding the genetic differences between these two serovars. In this study, we analyzed the genome sequences of 67 isolates belonging to L. interrogans serovars Copenhageni and Icterohaemorrhagiae to investigate the influence of spatial and temporal variations on DNA sequence diversity. Out of the 1072 SNPs identified, 276 were in non-coding regions and 796 in coding regions. Indel analyses identified 258 indels, out of which 191 were found in coding regions and 67 in non-coding regions. Our phylogenetic analyses based on SNP dataset revealed that both serovars are closely related but showed distinct spatial clustering. However, likelihood ratio test of the indel data statistically confirmed the presence of a frameshift mutation within a homopolymeric tract of lic12008 gene (related to LPS biosynthesis) in all the L. interrogans serovar Icterohaemorrhagiae strains but not in the Copenhageni strains. Therefore, this internal indel identified can genetically distinguish L. interrogans serovar Copenhageni from serovar Icterohaemorrhagiae with high discriminatory power. To our knowledge, this is the first study to identify global sequence variations (SNPs and Indels) in L. interrogans serovars Copenhageni and Icterohaemorrhagiae.
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Affiliation(s)
- Luciane A Santos
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States.,Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Brazil
| | - Haritha Adhikarla
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States
| | - Xiting Yan
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | - Zheng Wang
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | | | - Joseph M Vinetz
- Division of Infectious Diseases, Department of Medicine, University of California San Diego School of Medicine, La Jolla, CA, United States
| | | | - Rudy A Hartskeerl
- Royal Tropical Institute, KIT Biomedical Research, Amsterdam, Netherlands
| | - Marga G A Goris
- Royal Tropical Institute, KIT Biomedical Research, Amsterdam, Netherlands
| | | | | | - Jeffrey P Townsend
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | - Hongyu Zhao
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, United States
| | - Albert I Ko
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States.,Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Brazil
| | - Elsio A Wunder
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States.,Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Brazil
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6
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Martínez-García R, Nadell CD, Hartmann R, Drescher K, Bonachela JA. Cell adhesion and fluid flow jointly initiate genotype spatial distribution in biofilms. PLoS Comput Biol 2018; 14:e1006094. [PMID: 29659578 PMCID: PMC5901778 DOI: 10.1371/journal.pcbi.1006094] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 03/16/2018] [Indexed: 11/18/2022] Open
Abstract
Biofilms are microbial collectives that occupy a diverse array of surfaces. It is well known that the function and evolution of biofilms are strongly influenced by the spatial arrangement of different strains and species within them, but how spatiotemporal distributions of different genotypes in biofilm populations originate is still underexplored. Here, we study the origins of biofilm genetic structure by combining model development, numerical simulations, and microfluidic experiments using the human pathogen Vibrio cholerae. Using spatial correlation functions to quantify the differences between emergent cell lineage segregation patterns, we find that strong adhesion often, but not always, maximizes the size of clonal cell clusters on flat surfaces. Counterintuitively, our model predicts that, under some conditions, investing in adhesion can reduce rather than increase clonal group size. Our results emphasize that a complex interaction between fluid flow and cell adhesiveness can underlie emergent patterns of biofilm genetic structure. This structure, in turn, has an outsize influence on how biofilm-dwelling populations function and evolve.
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Affiliation(s)
- Ricardo Martínez-García
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, United States of America
| | - Carey D. Nadell
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, United States of America
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Raimo Hartmann
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Knut Drescher
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
- Department of Physics, Phillips-Universität Marburg, Marburg, Germany
| | - Juan A. Bonachela
- Marine Population Modeling Group, Department of Mathematics and Statistics, University of Strathclyde, Glasgow, Scotland, United Kingdom
- Department of Ecology, Evolution, and Natural Resources, Rutgers University, New Brunswick, New Jersey, United States of America
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7
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Ben Cheikh Y, Travers MA, Le Foll F. Infection dynamics of a V. splendidus strain pathogenic to Mytilus edulis: In vivo and in vitro interactions with hemocytes. FISH & SHELLFISH IMMUNOLOGY 2017; 70:515-523. [PMID: 28935598 DOI: 10.1016/j.fsi.2017.09.047] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 09/10/2017] [Accepted: 09/15/2017] [Indexed: 06/07/2023]
Abstract
The pathogenic strain V. splendidus 10/068 1T1 has previously been reported for its virulence to the blue mussel and for its capacity to alter immune responses. In this study, we expanded the knowledge on hemocyte-pathogen interactions by using in vitro and in vivo assays. V. splendidus 10/068 1T1 severely inhibited cell adhesion and acidic vacuole formation unlike the innocuous phylogenetically related V. splendidus 12/056 M24T1 which had no effect on these cell functions. Furthermore, the virulent bacteria decreased hemocyte viability (59% of viability after 24 h). Infection dynamics were explored by using a model based on water tank cohabitation with septic mussels infected by GFP-tagged V. splendidus 10/068 1T1. Experimental infections were successfully produced (16.6% and 45% mortalities in 3 days and 6 days). The amount of GFP Vibrio in seawater decreased during the experiment suggesting its horizontal transfer from diseased animals to healthy ones. At the same time periods, bacteria were detected in hemocytes and in various organs and caused necrosis especially in gills. Total hemocyte count and viability were affected. Taken together, our results indicate that the pathogen V. splendidus 10/068 1T1 colonizes its host both by bypassing external defense barriers and impairing hemocyte defense activities.
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Affiliation(s)
- Yosra Ben Cheikh
- UMR-I 02 INERIS-URCA-ULH SEBIO / Environmental Stresses and Aquatic Biomonitoring, FR CNRS 3730 Scale, Université Le Havre Normandie, F-76063, Le Havre Cedex, France.
| | - Marie-Agnès Travers
- Ifremer, SG2M-LGPMM, Laboratoire de Génétique et Pathologie des Mollusques Marins Avenue de Mus de Loup, 17390 La Tremblade, France
| | - Frank Le Foll
- UMR-I 02 INERIS-URCA-ULH SEBIO / Environmental Stresses and Aquatic Biomonitoring, FR CNRS 3730 Scale, Université Le Havre Normandie, F-76063, Le Havre Cedex, France
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8
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Bruce JB, Cooper GA, Chabas H, West SA, Griffin AS. Cheating and resistance to cheating in natural populations of the bacteriumPseudomonas fluorescens. Evolution 2017; 71:2484-2495. [DOI: 10.1111/evo.13328] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 07/14/2017] [Accepted: 08/08/2017] [Indexed: 12/11/2022]
Affiliation(s)
- John B. Bruce
- Department of Zoology; University of Oxford; Oxford UK
| | - Guy A. Cooper
- Department of Zoology; University of Oxford; Oxford UK
| | - Hélène Chabas
- CEFE UMR 5175, CNRS-Université de Montpellier; Université Paul-Valéry Montpellier; Montpellier Cedex 5 France
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9
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Pollitt EJG, Diggle SP. Defining motility in the Staphylococci. Cell Mol Life Sci 2017; 74:2943-2958. [PMID: 28378043 PMCID: PMC5501909 DOI: 10.1007/s00018-017-2507-z] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 02/16/2017] [Accepted: 03/14/2017] [Indexed: 01/17/2023]
Abstract
The ability of bacteria to move is critical for their survival in diverse environments and multiple ways have evolved to achieve this. Two forms of motility have recently been described for Staphylococcus aureus, an organism previously considered to be non-motile. One form is called spreading, which is a type of sliding motility and the second form involves comet formation, which has many observable characteristics associated with gliding motility. Darting motility has also been observed in Staphylococcus epidermidis. This review describes how motility is defined and how we distinguish between passive and active motility. We discuss the characteristics of the various forms of Staphylococci motility, the molecular mechanisms involved and the potential future research directions.
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Affiliation(s)
- Eric J G Pollitt
- Department of Biomedical Science, Western Bank, University of Sheffield, Sheffield, UK
| | - Stephen P Diggle
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA.
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10
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The Fitness of Pseudomonas aeruginosa Quorum Sensing Signal Cheats Is Influenced by the Diffusivity of the Environment. mBio 2017; 8:mBio.00353-17. [PMID: 28465424 PMCID: PMC5414003 DOI: 10.1128/mbio.00353-17] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Experiments examining the social dynamics of bacterial quorum sensing (QS) have focused on mutants which do not respond to signals and the role of QS-regulated exoproducts as public goods. The potential for QS signal molecules to themselves be social public goods has received much less attention. Here, we analyze how signal-deficient (lasI) mutants of the opportunistic pathogen Pseudomonas aeruginosa interact with wild-type cells in an environment where QS is required for growth. We show that when growth requires a "private" intracellular metabolic mechanism activated by the presence of QS signal, lasI mutants act as social cheats and outcompete signal-producing wild-type bacteria in mixed cultures, because they can exploit the signals produced by wild-type cells. However, reducing the ability of signal molecules to diffuse through the growth medium results in signal molecules becoming less accessible to mutants, leading to reduced cheating. Our results indicate that QS signal molecules can be considered social public goods in a way that has been previously described for other exoproducts but that spatial structuring of populations reduces exploitation by noncooperative signal cheats.IMPORTANCE Bacteria communicate via signaling molecules to regulate the expression of a whole range of genes. This process, termed quorum sensing (QS), moderates bacterial metabolism under many environmental conditions, from soil and water (where QS-regulated genes influence nutrient cycling) to animal hosts (where QS-regulated genes determine pathogen virulence). Understanding the ecology of QS could therefore yield vital clues to how we might modify bacterial behavior for environmental or clinical gains. Here, we demonstrate that QS signals act as shareable public goods. This means that their evolution, and therefore population-level responses to interference with QS, will be constrained by population structure. Further, we show that environmental structure (constraints on signal diffusion) alters the accessibility of QS signals and demonstrates that we need to consider population and environmental structure to help us further our understanding of QS signaling systems.
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11
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Bertani I, Abbruscato P, Piffanelli P, Subramoni S, Venturi V. Rice bacterial endophytes: isolation of a collection, identification of beneficial strains and microbiome analysis. ENVIRONMENTAL MICROBIOLOGY REPORTS 2016; 8:388-98. [PMID: 27038229 DOI: 10.1111/1758-2229.12403] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 03/04/2016] [Indexed: 05/12/2023]
Abstract
Endophytes are harmless or beneficial microorganisms that live inside plants between cells. The relationship they develop with the plant as well as their potential role in plant health is at large unexplored and it is believed that the opportunity to find new and interesting endophytes among the large variety of plants is great. Here, we present the isolation and analysis of a large collection of endophytes from one cultivar of rice grown in Italy. A total 1318 putative endophytes were isolated from roots, leaves and stems from rice grown in submerged and dry conditions and a working collection of 229 isolates was created. Among these, several isolates were confirmed to be endophytes and a few displayed the trait of plant growth promotion. A cultivation independent analysis via 16S rDNA amplicons of the bacterial community of the endosphere was also performed providing information on bacterial diversity in the rice endopshere.
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Affiliation(s)
- Iris Bertani
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149, Trieste, Italy
| | - Pamela Abbruscato
- Parco Tecnologico Padano (PTP) via A. Einstein Loc. Codazza, 26900, Lodi, Italy
| | - Pietro Piffanelli
- Parco Tecnologico Padano (PTP) via A. Einstein Loc. Codazza, 26900, Lodi, Italy
| | - Sujatha Subramoni
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149, Trieste, Italy
| | - Vittorio Venturi
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149, Trieste, Italy
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12
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Ren Y, Yang J, Chen S. The fate of a nitrobenzene-degrading bacterium in pharmaceutical wastewater treatment sludge. CHEMOSPHERE 2015; 141:13-18. [PMID: 26086561 DOI: 10.1016/j.chemosphere.2015.05.098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 05/09/2015] [Accepted: 05/29/2015] [Indexed: 06/04/2023]
Abstract
This paper describes the fate of a nitrobenzene-degrading bacterium, Klebsiella oxytoca NBA-1, which was isolated from a pharmaceutical wastewater treatment facility. The 90-day survivability of strain NBA-1 after exposure to sludge under anaerobic and aerobic conditions was investigated. The bacterium was inoculated into sludge amended with glucose and p-chloronitrobenzene (p-CNB) to compare the bacterial community variations between the modified sludge and nitrobenzene amendment. The results showed that glucose had no obvious effect on nitrobenzene biodegradation in the co-metabolism process, regardless of the presence/absence of oxygen. When p-CNB was added under anaerobic conditions, the biodegradation rate of nitrobenzene remained unchanged although p-CNB inhibited the production of aniline. The diversity of the microbial community increased and NBA-1 continued to be one of the dominant strains. Under aerobic conditions, the degradation rate of both nitrobenzene and p-CNB was only 20% of that under anaerobic conditions. p-CNB had a toxic effect on the microorganisms in the sludge so that most of the DGGE (denaturing gradient gel electrophoresis) bands, including that of NBA-1, began to disappear under aerobic conditions after 90days of exposure. These data show that the bacterial community was stable under anaerobic conditions and the microorganisms, including NBA-1, were more resistant to the adverse environment.
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Affiliation(s)
- Yuan Ren
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Panyu District, Guangzhou 510006, PR China; The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, PR China; The Key Laboratory of Environmental Protection and Eco-Remediation of Guangdong Regular Higher Education Institutions, PR China.
| | - Juan Yang
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Panyu District, Guangzhou 510006, PR China
| | - Shaoyi Chen
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Panyu District, Guangzhou 510006, PR China
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13
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Scutera S, Zucca M, Savoia D. Novel approaches for the design and discovery of quorum-sensing inhibitors. Expert Opin Drug Discov 2014; 9:353-66. [DOI: 10.1517/17460441.2014.894974] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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