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Zhu B, Cen Z, Chen Y, Shang K, Zhai J, Han M, Wang J, Chen Z, Wei T, Han Z. α-Pyrone mediates quorum sensing through the conservon system in Nocardiopsis sp. Microbiol Res 2024; 285:127767. [PMID: 38776619 DOI: 10.1016/j.micres.2024.127767] [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] [Received: 01/30/2024] [Revised: 05/10/2024] [Accepted: 05/13/2024] [Indexed: 05/25/2024]
Abstract
Actinobacteria produce a plethora of bioactive secondary metabolites that are often regulated by quorum-sensing signaling molecules via specific binding to their cognate TetR-type receptors. Here, we identified monocyclic α-pyrone as a new class of actinobacterial signaling molecules influencing quorum sensing process in Nocardiopsis sp. LDBS0036, primarily evidenced by a significant reduction in the production of phenazines in the pyrone-null mutant compared to the wild-type strain. Exogenous addition of the α-pyrone can partially restore the expression of some pathways to the wild strain level. Moreover, a unique multicomponent system referred to as a conservon, which is widespread in actinobacteria and generally contains four or five functionally conserved proteins, may play an important role in detecting and transmitting α-pyrone signals in LDBS0036. We found the biosynthetic gene clusters of α-pyrone and their associated conservon genes are highly conserved in Nocardiopsis, indicating the widespread prevalence and significant function of this regulate mechanism within Nocardiopsis genus. Furthermore, homologous α-pyrones from different actinobacterial species were also found to mediate interspecies communication. Our results thus provide insights into a novel quorum-sensing signaling system and imply that various modes of bacterial communication remain undiscovered.
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Affiliation(s)
- Boyu Zhu
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ziyun Cen
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yiqiu Chen
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; Hainan University, Haikou, Hainan 570100, China
| | - Kun Shang
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China
| | - Ji'an Zhai
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Meigui Han
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiawei Wang
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; Hainan University, Haikou, Hainan 570100, China
| | - Zhiyong Chen
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China
| | - Taoshu Wei
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhuang Han
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China.
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2
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Rossetto V, Moore-Machacek A, Woods DF, Galvão HM, Shanahan RM, Hickey A, O'Leary N, O'Gara F, McGlacken GP, Reen FJ. Structural modification of the Pseudomonas aeruginosa alkylquinoline cell-cell communication signal, HHQ, leads to benzofuranoquinolines with anti-virulence behaviour in ESKAPE pathogens. MICROBIOLOGY (READING, ENGLAND) 2023; 169. [PMID: 36862576 DOI: 10.1099/mic.0.001303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Microbial populations have evolved intricate networks of negotiation and communication through which they can coexist in natural and host ecosystems. The nature of these systems can be complex and they are, for the most part, poorly understood at the polymicrobial level. The Pseudomonas Quinolone Signal (PQS) and its precursor 4-hydroxy-2-heptylquinoline (HHQ) are signal molecules produced by the important nosocomial pathogen
Pseudomonas aeruginosa
. They are known to modulate the behaviour of co-colonizing bacterial and fungal pathogens such as Bacillus atropheaus, Candida albicans and Aspergillus fumigatus. While the structural basis for alkyl-quinolone signalling within
P. aeruginosa
has been studied extensively, less is known about how structural derivatives of these molecules can influence multicellular behaviour and population-level decision-making in other co-colonizing organisms. In this study, we investigated a suite of small molecules derived initially from the HHQ framework, for anti-virulence activity against ESKAPE pathogens, at the species and strain levels. Somewhat surprisingly, with appropriate substitution, loss of the alkyl chain (present in HHQ and PQS) did not result in a loss of activity, presenting a more easily accessible synthetic framework for investigation. Virulence profiling uncovered significant levels of inter-strain variation among the responses of clinical and environmental isolates to small-molecule challenge. While several lead compounds were identified in this study, further work is needed to appreciate the extent of strain-level tolerance to small-molecule anti-infectives among pathogenic organisms.
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Affiliation(s)
- Veronica Rossetto
- Faculty of Science and Technology, Universidade do Algarve, Algarve, Portugal.,School of Microbiology, University College Cork, Cork, Ireland
| | | | - David F Woods
- School of Microbiology, University College Cork, Cork, Ireland
| | - Helena M Galvão
- Faculty of Science and Technology, Universidade do Algarve, Algarve, Portugal
| | - Rachel M Shanahan
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Aobha Hickey
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Niall O'Leary
- School of Microbiology, University College Cork, Cork, Ireland
| | - Fergal O'Gara
- School of Microbiology, University College Cork, Cork, Ireland.,Biomerit Research Centre, School of Microbiology, University College Cork, Cork, Ireland.,Wal-yan Respiratory Research Centre, Telethon Kids Institute, Perth, WA, Australia
| | - Gerard P McGlacken
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland.,Synthesis and Solid State Pharmaceutical Centre, University College Cork, Cork, Ireland
| | - F Jerry Reen
- School of Microbiology, University College Cork, Cork, Ireland.,Synthesis and Solid State Pharmaceutical Centre, University College Cork, Cork, Ireland
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3
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Jamil F, Mukhtar H, Fouillaud M, Dufossé L. Rhizosphere Signaling: Insights into Plant-Rhizomicrobiome Interactions for Sustainable Agronomy. Microorganisms 2022; 10:microorganisms10050899. [PMID: 35630345 PMCID: PMC9147336 DOI: 10.3390/microorganisms10050899] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 04/19/2022] [Accepted: 04/21/2022] [Indexed: 02/01/2023] Open
Abstract
Rhizospheric plant-microbe interactions have dynamic importance in sustainable agriculture systems that have a reduced reliance on agrochemicals. Rhizosphere signaling focuses on the interactions between plants and the surrounding symbiotic microorganisms that facilitate the development of rhizobiome diversity, which is beneficial for plant productivity. Plant-microbe communication comprises intricate systems that modulate local and systemic defense mechanisms to mitigate environmental stresses. This review deciphers insights into how the exudation of plant secondary metabolites can shape the functions and diversity of the root microbiome. It also elaborates on how rhizosphere interactions influence plant growth, regulate plant immunity against phytopathogens, and prime the plant for protection against biotic and abiotic stresses, along with some recent well-reported examples. A holistic understanding of these interactions can help in the development of tailored microbial inoculants for enhanced plant growth and targeted disease suppression.
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Affiliation(s)
- Fatima Jamil
- Institute of Industrial Biotechnology, Government College University, Lahore 54000, Pakistan;
| | - Hamid Mukhtar
- Institute of Industrial Biotechnology, Government College University, Lahore 54000, Pakistan;
- Correspondence: (H.M.); (M.F.); Tel.: +92-333-424-5581 (H.M.); +262-262-483-363 (M.F.)
| | - Mireille Fouillaud
- CHEMBIOPRO Chimie et Biotechnologie des Produits Naturels, Faculté des Sciences et Technologies, Université de la Réunion, F-97490 Sainte-Clotilde, Ile de La Réunion, France
- Correspondence: (H.M.); (M.F.); Tel.: +92-333-424-5581 (H.M.); +262-262-483-363 (M.F.)
| | - Laurent Dufossé
- CHEMBIOPRO Chimie et Biotechnologie des Produits Naturels, ESIROI Département Agroalimentaire, Université de la Réunion, F-97490 Sainte-Clotilde, Ile de La Réunion, France;
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4
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Ruiz CH, Osorio-Llanes E, Trespalacios MH, Mendoza-Torres E, Rosales W, Gómez CMM. Quorum Sensing Regulation as a Target for Antimicrobial Therapy. Mini Rev Med Chem 2021; 22:848-864. [PMID: 34856897 DOI: 10.2174/1389557521666211202115259] [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: 10/04/2020] [Revised: 05/20/2021] [Accepted: 09/04/2021] [Indexed: 11/22/2022]
Abstract
Some bacterial species use a cell-to-cell communication mechanism called Quorum Sensing (QS). Bacteria release small diffusible molecules, usually termed signals which allow the activation of beneficial phenotypes that guarantee bacterial survival and the expression of a diversity of virulence genes in response to an increase in population density. The study of the molecular mechanisms that relate signal molecules with bacterial pathogenesis is an area of growing interest due to its use as a possible therapeutic alternative through the development of synthetic analogues of autoinducers as a strategy to regulate bacterial communication as well as the study of bacterial resistance phenomena, the study of these relationships is based on the structural diversity of natural or synthetic autoinducers and their ability to inhibit bacterial QS, which can be approached with a molecular perspective from the following topics: i) Molecular signals and their role in QS regulation; ii) Strategies in the modulation of Quorum Sensing; iii) Analysis of Bacterial QS circuit regulation strategies; iv) Structural evolution of natural and synthetic autoinducers as QS regulators. This mini-review allows a molecular view of the QS systems, showing a perspective on the importance of the molecular diversity of autoinducer analogs as a strategy for the design of new antimicrobial agents.
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Affiliation(s)
- Caterine Henríquez Ruiz
- Grupo de Investigación en Química Orgánica y Biomédica. Faculty of Basic Sciences. Universidad del Atlántico. Barranquilla. Colombia
| | - Estefanie Osorio-Llanes
- Faculty of Exact and Natural sciences. Grupo de Investigación Avanzada en Biomedicina. Universidad Libre. Barranquilla. Colombia
| | - Mayra Hernández Trespalacios
- Grupo de Investigación en Química Orgánica y Biomédica. Faculty of Basic Sciences. Universidad del Atlántico. Barranquilla. Colombia
| | - Evelyn Mendoza-Torres
- Faculty of Health Sciences. Grupo de Investigación Avanzada en Biomedicina-Universidad Libre. Barranquilla. Colombia
| | - Wendy Rosales
- Faculty of Exact and Natural sciences. Grupo de Investigación Avanzada en Biomedicina. Universidad Libre. Barranquilla. Colombia
| | - Carlos Mario Meléndez Gómez
- Grupo de Investigación en Química Orgánica y Biomédica. Faculty of Basic Sciences. Universidad del Atlántico. Barranquilla. Colombia
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5
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Shah A, Nazari M, Antar M, Msimbira LA, Naamala J, Lyu D, Rabileh M, Zajonc J, Smith DL. PGPR in Agriculture: A Sustainable Approach to Increasing Climate Change Resilience. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2021. [DOI: 10.3389/fsufs.2021.667546] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Growing environmental concerns are potentially narrowing global yield capacity of agricultural systems. Climate change is the most significant problem the world is currently facing. To meet global food demand, food production must be doubled by 2050; over exploitation of arable lands using unsustainable techniques might resolve food demand issues, but they have negative environmental effects. Current crop production systems are a major reason for changing global climate through diminishing biodiversity, physical and chemical soil degradation, and water pollution. The over application of fertilizers and pesticides contribute to climate change through greenhouse gas emissions (GHG) and toxic soil depositions. At this crucial time, there is a pressing need to transition to more sustainable crop production practices, ones that concentrate more on promoting sustainable mechanisms, which enable crops to grow well in resource limited and environmentally challenging environments, and also develop crops with greater resource use efficiency that have optimum sustainable yields across a wider array of environmental conditions. The phytomicrobiome is considered as one of the best strategies; a better alternative for sustainable agriculture, and a viable solution to meet the twin challenges of global food security and environmental stability. Use of the phytomicrobiome, due to its sustainable and environmentally friendly mechanisms of plant growth promotion, is becoming more widespread in the agricultural industry. Therefore, in this review, we emphasize the contribution of beneficial phytomicrobiome members, particularly plant growth promoting rhizobacteria (PGPR), as a strategy to sustainable improvement of plant growth and production in the face of climate change. Also, the roles of soil dwelling microbes in stress amelioration, nutrient supply (nitrogen fixation, phosphorus solubilization), and phytohormone production along with the factors that could potentially affect their efficiency have been discussed extensively. Lastly, limitations to expansion and use of biobased techniques, for instance, the perspective of crop producers, indigenous microbial competition and regulatory approval are discussed. This review largely focusses on the importance and need of sustainable and environmentally friendly approaches such as biobased/PGPR-based techniques in our agricultural systems, especially in the context of current climate change conditions, which are almost certain to worsen in near future.
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6
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Wang C, Wang S, Jiao X, Yang B, Liang S, Luo Z, Mao L. Periodic density as an endpoint of customized plankton community responses to petroleum hydrocarbons: A level of toxic effect should be matched with a suitable time scale. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 201:110723. [PMID: 32485490 DOI: 10.1016/j.ecoenv.2020.110723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 04/28/2020] [Accepted: 05/03/2020] [Indexed: 06/11/2023]
Abstract
As an endpoint of community response to contaminants, average periodic density of populations (APDP) has been introduced to model species interactions in a community with 4 planktonic species. An ecological model for the community was developed by means of interspecific relationship including competition and predation to calculate the APDP. As a case study, we reported here the ecotoxicological effects of petroleum hydrocarbons (PHC) collected from Bohai oil field on densities of two algae, Platymonas subcordiformis and Isochrysis galbana, a rotifer, Brachionus plicatilis, and of a cladocera, Penilia avirostris, in single species and a microcosm experiment. Time scales expressing toxic effect increased with increasing levels of toxic effect from molecule to community. Remarkable periodic changes in densities were found during the tests in microcosm experiment, revealing a strong species reaction. The minimum time scale characterizing toxic effect at a community level should be the common cycle of population densities of the microcosm. In addition, the cycles of plankton densities shortened in general with increasing PHC, showing an evident toxic effect on the microcosm. Using APDP as the endpoint, a threshold concentration for the modeled microcosm was calculated to be 0.404 mg-PHC L-1. The APDP was found to be more sensitive and reliable than the standing crops of populations as the endpoint. This indicated that the APDP, an endpoint at the community level, could be quantitatively related to the endpoints at the population level, and led to the quantitative concentration-toxic effect relationship at the community level.
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Affiliation(s)
- Changyou Wang
- School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
| | - Siwen Wang
- School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Xinming Jiao
- Jiangsu Environmental Monitoring Center, Nanjing, 210036, China
| | - Bin Yang
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou, 535011, China
| | - Shengkang Liang
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China
| | - Zhuhua Luo
- School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Longjiang Mao
- School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing, 210044, China
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7
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Sharma A, Singh P, Sarmah BK, Nandi SP. Quorum sensing: its role in microbial social networking. Res Microbiol 2020; 171:159-164. [PMID: 32592751 DOI: 10.1016/j.resmic.2020.06.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 10/24/2022]
Abstract
Twentieth century observed a huge paradigm shift in the field of sociobiology, which moved from social intelligence of animals to microbes. Quorum Sensing Molecules (QSMs) are the small chemical molecules, which establish the mode of communication among microbes, and is called Quorum Sensing (QS). These molecules are crucial for determining the decisions of large groups of cells, which is a density-dependent process. Thus, this mechanism draws a very thin line between bacteria that are actually prokaryotes and clustered bacteria mimicking eukaryotes. This review discusses about the designs of microbial communication networks, and the role of QS in plant-microbe interaction.
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Affiliation(s)
- Angkita Sharma
- Amity Institute of Biotechnology, Amity University, Noida, 201313, Uttar Pradesh, India.
| | - Pooja Singh
- Amity Institute of Biotechnology, Amity University, Noida, 201313, Uttar Pradesh, India.
| | - Bidyut Kr Sarmah
- DBT-AAU Centre, Assam Agricultural University, Jorhat, 785013, Assam, India.
| | - Shoma Paul Nandi
- Amity Institute of Biotechnology, Amity University, Noida, 201313, Uttar Pradesh, India.
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8
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Bukhat S, Imran A, Javaid S, Shahid M, Majeed A, Naqqash T. Communication of plants with microbial world: Exploring the regulatory networks for PGPR mediated defense signaling. Microbiol Res 2020; 238:126486. [PMID: 32464574 DOI: 10.1016/j.micres.2020.126486] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/20/2020] [Accepted: 03/28/2020] [Indexed: 02/01/2023]
Abstract
Agricultural manipulation of potentially beneficial rhizosphere microbes is increasing rapidly due to their multi-functional plant-protective and growth related benefits. Plant growth promoting rhizobacteria (PGPR) are mostly non-pathogenic microbes which exert direct benefits on plants while there are rhizosphere bacteria which indirectly help plant by ameliorating the biotic and/or abiotic stress or induction of defense response in plant. Regulation of these direct or indirect effect takes place via highly specialized communication system induced at multiple levels of interaction i.e., inter-species, intra-species, and inter-kingdom. Studies have provided insights into the functioning of signaling molecules involved in communication and induction of defense responses. Activation of host immune responses upon bacterial infection or rhizobacteria perception requires comprehensive and precise gene expression reprogramming and communication between hosts and microbes. Majority of studies have focused on signaling of host pattern recognition receptors (PRR) and nod-like receptor (NLR) and microbial effector proteins under mining the role of other components such as mitogen activated protein kinase (MAPK), microRNA, histone deacytylases. The later ones are important regulators of gene expression reprogramming in plant immune responses, pathogen virulence and communications in plant-microbe interactions. During the past decade, inoculation of PGPR has emerged as potential strategy to induce biotic and abiotic stress tolerance in plants; hence, it is imperative to expose the basis of these interactions. This review discusses microbes and plants derived signaling molecules for their communication, regulatory and signaling networks of PGPR and their different products that are involved in inducing resistance and tolerance in plants against environmental stresses and the effect of defense signaling on root microbiome. We expect that it will lead to the development and exploitation of beneficial microbes as source of crop biofertilizers in climate changing scenario enabling more sustainable agriculture.
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Affiliation(s)
- Sherien Bukhat
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, 60800 Multan, Pakistan.
| | - Asma Imran
- National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box 577, Jhang Road, Faisalabad, Pakistan.
| | - Shaista Javaid
- Institute of Molecular Biology and Biotechnology, University of Lahore Main Campus, Defense road, Lahore, Pakistan.
| | - Muhammad Shahid
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad 38000, Pakistan.
| | - Afshan Majeed
- Department of Soil and Environmental Sciences, The University of Poonch, Rawalakot, Azad Jammu and Kashmir, Pakistan.
| | - Tahir Naqqash
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, 60800 Multan, Pakistan.
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9
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Wang C, Jiao X, Liu G. A toxic effect at molecular level can be expressed at community level: A case study on toxic hierarchy. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 693:133573. [PMID: 31374497 DOI: 10.1016/j.scitotenv.2019.07.379] [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: 06/09/2019] [Revised: 07/22/2019] [Accepted: 07/22/2019] [Indexed: 06/10/2023]
Abstract
This study demonstrated hierarchical toxicity and addressed the relevance and differences of toxic effects at the molecular, individual, population, and community levels. Superoxide dismutase (SOD) activity, photosynthetic oxygen production, filtration rate, life span and densities of Platymonas helgolandica var. tsingtaoensis, Isochrysis galbana, and Brachionus plicatilis in single-species tests and customized community tests were examined in response to a concentration gradient of aniline ranging from 0 to 50.0 mg L-1. The SOD activity was the most sensitive endpoint with the fastest response to aniline according to the calculated no-detection of toxic effect concentration (NDEC) and the EC50. The individual- and population-level endpoints, showing a lower response to aniline, could be constructed from the SOD activity in a stepwise manner. A multi-scale hierarchical model with endpoints at 4 levels was used to characterize toxic effects, at the scales of time and size. Linkage of SOD activity to toxic effects at a community level was established level by level to express the change in the customized community with the concentration of aniline. The calculated threshold concentration of aniline for the customized community was nearly equal to the minimum NDEC, demonstrating as great an impact on interactions by the toxic effect at subpopulation-level as that at the community level. However, we identified a trend of higher sensitivities of measured endpoints at sub-population level, decreasing sensitivity at higher levels but a great variety of sensitivities at community level. Although the characteristics of toxic effects are different at different levels, the structure and process of endpoints at adjacent levels are related to and interact with each other. The resulted indirect effects, together with direct effect, determine the toxic effect at every levels of biological complexity. The toxic effects at adjacent levels should be studied at the same time to better understand the ecological risk of contaminants.
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Affiliation(s)
- Changyou Wang
- School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, China; Jiangsu Research Center for Ocean Survey Technology, Nanjing University of Information Science and Technology, Nanjing 210044, China.
| | - Xinming Jiao
- Jiangsu Environmental Monitoring Center, Nanjing 210036, China
| | - Gang Liu
- School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, China; Jiangsu Research Center for Ocean Survey Technology, Nanjing University of Information Science and Technology, Nanjing 210044, China
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10
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Bartolini M, Grau R. Assessing Different Ways of Bacillus subtilis Spreading over Abiotic Surfaces. Bio Protoc 2019; 9:e3425. [PMID: 33654922 DOI: 10.21769/bioprotoc.3425] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 10/16/2019] [Accepted: 10/22/2019] [Indexed: 11/02/2022] Open
Abstract
Surface-associate motility on biotic and abiotic environments is a key mechanism used by the model bacterium Bacillus subtilis and its closest relatives (i.e., B. amyloliquefaciens, B. thuringiensis, B. cereus, B. pumilus) for surface colonization and spreading across surfaces. The study of this mechanism in a research, industrial or clinic laboratory is essential; however, precautions should be taken for the reproducibility of the results, for example, the procedure to inoculate the bacteria on the testing plate, the humidity of the plate and the agar concentration. In this protocol, we describe, using Bacillus subtilis, how to perform these assays and, in addition, we show how by varying the agar concentration in the plate, you can make a first approximation of what type of motility has other bacterial species.
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Affiliation(s)
- Marco Bartolini
- Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, CONICET, Rosario, Argentina
| | - Roberto Grau
- Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, CONICET, Rosario, Argentina
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11
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Microbial Electrosynthesis I: Pure and Defined Mixed Culture Engineering. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2019; 167:181-202. [PMID: 29071400 DOI: 10.1007/10_2017_17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In the past 6 years, microbial bioelectrochemistry has strongly increased in attraction and audience when expanding from mainly environmental technology applications to biotechnology. In particular, the promise to combine electrosynthesis with microbial catalysis opens attractive approaches for new sustainable redox-cofactor recycling, redox-balancing, or even biosynthesis processes. Much of this promise is still not fulfilled, but it has opened and fueled entirely new research areas in this discipline. Activities in designing, tailoring, and applying specific microbial catalysts as pure or defined co-cultures for defined target bioproductions are greatly accelerating. This chapter gives an overview of the current progress as well as the emerging trends in molecular and ecological engineering of defined microbial biocatalysts to prepare them for evolving microbial electrosynthesis processes. In addition, the multitude of microbial electrosynthetic processes with complex undefined mixed cultures is covered by ter Heijne et al. (Adv Biochem Eng Biotechnol. https://doi.org/10.1007/10_2017_15 , 2017). Graphical Abstract.
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12
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Palmer AG, Senechal AC, Haire TC, Mehta NP, Valiquette SD, Blackwell HE. Selection of Appropriate Autoinducer Analogues for the Modulation of Quorum Sensing at the Host-Bacterium Interface. ACS Chem Biol 2018; 13:3115-3122. [PMID: 30296049 PMCID: PMC6239973 DOI: 10.1021/acschembio.8b00676] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Bacteria regulate a variety of phenotypes in response to their population density using quorum sensing (QS). This phenomenon is regulated by small molecule or peptide signals, the best characterized of which are the N-acyl l-homoserine lactones (AHLs) utilized by Gram-negative bacteria. As many QS-controlled phenotypes, notably pathogenicity and symbiosis, can profoundly impact host eukaryotes, there is significant interest in developing methods for modulating QS signaling and either ameliorating or augmenting these phenotypes. One strategy has been the use of non-native AHL analogues to agonize or antagonize specific AHL receptors. This approach is complicated, however, by the potential for prospective hosts to respond to both native AHLs and synthetic analogues. Accordingly, identifying AHL analogues with little or no activity toward eukaryotes is important in developing QS modulation as a strategy for the regulation of prokaryotic behaviors. Herein, we utilize the model plant Arabidopsis thaliana to characterize eukaryotic responses to a variety of synthetic AHL analogues to identify structural elements of existing scaffolds that may elicit responses in prospective hosts. Our results indicate that, while many of these compounds have no discernible effect on A. thaliana, some elicit strong phenotypes similar to those produced by auxin, a hormone involved in almost all aspects of plant development. We outline concentrations and chemical scaffolds that are ideal for deployment on plant hosts for the regulation of QS. This approach should be exportable to other eukaryotes for the selection of optimal AHL tools for the study of QS at the host-microbe interface.
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Affiliation(s)
- Andrew G. Palmer
- Department of Biomedical and Chemical Engineering and Science, Florida Institute of Technology, 150 West University Blvd., Melbourne, FL 32901
| | - Amanda C. Senechal
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706
| | - Timothy C. Haire
- Department of Biomedical and Chemical Engineering and Science, Florida Institute of Technology, 150 West University Blvd., Melbourne, FL 32901
| | - Nidhi P. Mehta
- Department of Biomedical and Chemical Engineering and Science, Florida Institute of Technology, 150 West University Blvd., Melbourne, FL 32901
| | - Sara D. Valiquette
- Department of Biomedical and Chemical Engineering and Science, Florida Institute of Technology, 150 West University Blvd., Melbourne, FL 32901
| | - Helen E. Blackwell
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706
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D'Souza G, Shitut S, Preussger D, Yousif G, Waschina S, Kost C. Ecology and evolution of metabolic cross-feeding interactions in bacteria. Nat Prod Rep 2018; 35:455-488. [PMID: 29799048 DOI: 10.1039/c8np00009c] [Citation(s) in RCA: 248] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Literature covered: early 2000s to late 2017Bacteria frequently exchange metabolites with other micro- and macro-organisms. In these often obligate cross-feeding interactions, primary metabolites such as vitamins, amino acids, nucleotides, or growth factors are exchanged. The widespread distribution of this type of metabolic interactions, however, is at odds with evolutionary theory: why should an organism invest costly resources to benefit other individuals rather than using these metabolites to maximize its own fitness? Recent empirical work has shown that bacterial genotypes can significantly benefit from trading metabolites with other bacteria relative to cells not engaging in such interactions. Here, we will provide a comprehensive overview over the ecological factors and evolutionary mechanisms that have been identified to explain the evolution and maintenance of metabolic mutualisms among microorganisms. Furthermore, we will highlight general principles that underlie the adaptive evolution of interconnected microbial metabolic networks as well as the evolutionary consequences that result for cells living in such communities.
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Affiliation(s)
- Glen D'Souza
- Department of Environmental Systems Sciences, ETH-Zürich, Zürich, Switzerland
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Interkingdom signaling in plant-microbe interactions. SCIENCE CHINA-LIFE SCIENCES 2017; 60:785-796. [PMID: 28755299 DOI: 10.1007/s11427-017-9092-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 05/04/2017] [Indexed: 12/18/2022]
Abstract
The widespread communications between prokaryotes and eukaryotes via signaling molecules are believed to affect gene expression in both partners. During the communication process, the contacted organisms produce and release small molecules that establish communication channels between two kingdoms-this procedure is known as interkingdom signaling. Interkingdom communications are widespread between pathogenic or beneficial bacteria and their host plants, with diversified outcomes depending on the specific chemical-triggered signaling pathways. Deciphering the signals or language of this interkingdom communication and uncovering the underlying mechanisms are major current challenges in this field. It is evident that diverse signaling molecules can be produced or derived from bacteria and plants, and researchers have sought to identify these signals and explore the mechanisms of the signaling pathways. The results of such studies will lead to the development of strategies to improve plant disease resistance through controlling interkingdom signals, rather than directly killing the pathogenic bacteria. Also, the identification of signals produced by beneficial bacteria will be useful for agricultural applications. In this review, we summarize the recent progress of cross-kingdom interactions between plant and bacteria, and how LuxR-family transcription factors in plant associated bacterial quorum sensing system are involved in the interkingdom signaling.
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