1
|
Gilhar O, Ben-Navi LR, Olender T, Aharoni A, Friedman J, Kolodkin-Gal I. Multigenerational inheritance drives symbiotic interactions of the bacterium Bacillus subtilis with its plant host. Microbiol Res 2024; 286:127814. [PMID: 38954993 DOI: 10.1016/j.micres.2024.127814] [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: 04/13/2024] [Revised: 06/04/2024] [Accepted: 06/18/2024] [Indexed: 07/04/2024]
Abstract
Bacillus subtilis is a beneficial bacterium that supports plant growth and protects plants from bacterial, fungal, and viral infections. Using a simplified system of B. subtilis and Arabidopsis thaliana interactions, we studied the fitness and transcriptome of bacteria detached from the root over generations of growth in LB medium. We found that bacteria previously associated with the root or exposed to its secretions had greater stress tolerance and were more competitive in root colonization than bacteria not previously exposed to the root. Furthermore, our transcriptome results provide evidence that plant secretions induce a microbial stress response and fundamentally alter signaling by the cyclic nucleotide c-di-AMP, a signature maintained by their descendants. The changes in cellular physiology due to exposure to plant exudates were multigenerational, as they allowed not only the bacterial cells that colonized a new plant but also their descendants to have an advance over naive competitors of the same species, while the overall plasticity of gene expression and rapid adaptation were maintained. These changes were hereditary but not permanent. Our work demonstrates a bacterial memory manifested by multigenerational reversible adaptation to plant hosts in the form of activation of the stressosome, which confers an advantage to symbiotic bacteria during competition.
Collapse
Affiliation(s)
- Omri Gilhar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel; Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | | | - Tsviya Olender
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Asaph Aharoni
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Jonathan Friedman
- Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Ilana Kolodkin-Gal
- Scojen Institute for Synthetic Biology, Reichman University, Herzliya, Israel.
| |
Collapse
|
2
|
Mehdizadeh Gohari I, Edwards AN, McBride SM, McClane BA. The impact of orphan histidine kinases and phosphotransfer proteins on the regulation of clostridial sporulation initiation. mBio 2024; 15:e0224823. [PMID: 38477571 PMCID: PMC11210211 DOI: 10.1128/mbio.02248-23] [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] [Indexed: 03/14/2024] Open
Abstract
Sporulation is an important feature of the clostridial life cycle, facilitating survival of these bacteria in harsh environments, contributing to disease transmission for pathogenic species, and sharing common early steps that are also involved in regulating industrially important solvent production by some non-pathogenic species. Initial genomics studies suggested that Clostridia lack the classical phosphorelay that phosphorylates Spo0A and initiates sporulation in Bacillus, leading to the hypothesis that sporulation in Clostridia universally begins when Spo0A is phosphorylated by orphan histidine kinases (OHKs). However, components of the classical Bacillus phosphorelay were recently identified in some Clostridia. Similar Bacillus phosphorelay components have not yet been found in the pathogenic Clostridia or the solventogenic Clostridia of industrial importance. For some of those Clostridia lacking a classical phosphorelay, the involvement of OHKs in sporulation initiation has received support from genetic studies demonstrating the involvement of several apparent OHKs in their sporulation. In addition, several clostridial OHKs directly phosphorylate Spo0A in vitro. Interestingly, there is considerable protein domain diversity among the sporulation-associated OHKs in Clostridia. Further adding to the emergent complexity of sporulation initiation in Clostridia, several candidate OHK phosphotransfer proteins that were OHK candidates were shown to function as phosphatases that reduce sporulation in some Clostridia. The mounting evidence indicates that no single pathway explains sporulation initiation in all Clostridia and supports the need for further study to fully understand the unexpected and biologically fascinating mechanistic diversity of this important process among these medically and industrially important bacteria.
Collapse
Affiliation(s)
- Iman Mehdizadeh Gohari
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Adrianne N. Edwards
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, USA
| | - Shonna M. McBride
- Department of Microbiology and Immunology, Emory University School of Medicine, Emory Antibiotic Resistance Center, Atlanta, Georgia, USA
| | - Bruce A. McClane
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| |
Collapse
|
3
|
Parmar D, Rosado-Rosa JM, Shrout JD, Sweedler JV. Metabolic insights from mass spectrometry imaging of biofilms: A perspective from model microorganisms. Methods 2024; 224:21-34. [PMID: 38295894 PMCID: PMC11149699 DOI: 10.1016/j.ymeth.2024.01.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 12/17/2023] [Accepted: 01/16/2024] [Indexed: 02/05/2024] Open
Abstract
Biofilms are dense aggregates of bacterial colonies embedded inside a self-produced polymeric matrix. Biofilms have received increasing attention in medical, industrial, and environmental settings due to their enhanced survival. Their characterization using microscopy techniques has revealed the presence of structural and cellular heterogeneity in many bacterial systems. However, these techniques provide limited chemical detail and lack information about the molecules important for bacterial communication and virulence. Mass spectrometry imaging (MSI) bridges the gap by generating spatial chemical information with unmatched chemical detail, making it an irreplaceable analytical platform in the multi-modal imaging of biofilms. In the last two decades, over 30 species of biofilm-forming bacteria have been studied using MSI in different environments. The literature conveys both analytical advancements and an improved understanding of the effects of environmental variables such as host surface characteristics, antibiotics, and other species of microorganisms on biofilms. This review summarizes the insights from frequently studied model microorganisms. We share a detailed list of organism-wide metabolites, commonly observed mass spectral adducts, culture conditions, strains of bacteria, substrate, broad problem definition, and details of the MS instrumentation, such as ionization sources and matrix, to facilitate future studies. We also compared the spatial characteristics of the secretome under different study designs to highlight changes because of various environmental influences. In addition, we highlight the current limitations of MSI in relation to biofilm characterization to enable cross-comparison between experiments. Overall, MSI has emerged to become an important approach for the spatial/chemical characterization of bacterial biofilms and its use will continue to grow as MSI becomes more accessible.
Collapse
Affiliation(s)
- Dharmeshkumar Parmar
- Department of Chemistry and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Joenisse M Rosado-Rosa
- Department of Chemistry and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Joshua D Shrout
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, United States; Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, United States
| | - Jonathan V Sweedler
- Department of Chemistry and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States.
| |
Collapse
|
4
|
Pomerleau M, Charron-Lamoureux V, Léonard L, Grenier F, Rodrigue S, Beauregard PB. Adaptive laboratory evolution reveals regulators involved in repressing biofilm development as key players in Bacillus subtilis root colonization. mSystems 2024; 9:e0084323. [PMID: 38206029 PMCID: PMC10878085 DOI: 10.1128/msystems.00843-23] [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: 08/10/2023] [Accepted: 12/04/2023] [Indexed: 01/12/2024] Open
Abstract
Root-associated microorganisms play an important role in plant health, such as plant growth-promoting rhizobacteria (PGPR) from the Bacillus and Pseudomonas genera. Although bacterial consortia including these two genera would represent a promising avenue to efficient biofertilizer formulation, we observed that Bacillus subtilis root colonization is decreased by the presence of Pseudomonas fluorescens and Pseudomonas protegens. To determine if B. subtilis can adapt to the inhibitory effect of Pseudomonas on roots, we conducted adaptative laboratory evolution experiments with B. subtilis in mono-association or co-cultured with P. fluorescens on tomato plant roots. Evolved isolates with various colony morphology and stronger colonization capacity of both tomato plant and Arabidopsis thaliana roots emerged rapidly from the two evolution experiments. Certain evolved isolates also had better fitness on the root in the presence of other Pseudomonas species. In all independent lineages, whole-genome resequencing revealed non-synonymous mutations in genes ywcC or sinR encoding regulators involved in repressing biofilm development, suggesting their involvement in enhanced root colonization. These findings provide insights into the molecular mechanisms underlying B. subtilis adaptation to root colonization and highlight the potential of directed evolution to enhance the beneficial traits of PGPR.IMPORTANCEIn this study, we aimed to enhance the abilities of the plant-beneficial bacterium Bacillus subtilis to colonize plant roots in the presence of competing Pseudomonas bacteria. To achieve this, we conducted adaptive laboratory experiments, allowing Bacillus to evolve in a defined environment. We successfully obtained strains of Bacillus that were more effective at colonizing plant roots than the ancestor strain. To identify the genetic changes driving this improvement, we sequenced the genomes of these evolved strains. Interestingly, mutations that facilitated the formation of robust biofilms on roots were predominant. Many of these evolved Bacillus isolates also displayed the remarkable ability to outcompete Pseudomonas species. Our research sheds light on the mutational paths selected in Bacillus subtilis to thrive in root environments and offers exciting prospects for improving beneficial traits in plant growth-promoting microorganisms. Ultimately, this could pave the way for the development of more effective biofertilizers and sustainable agricultural practices.
Collapse
Affiliation(s)
- Maude Pomerleau
- Département de biologie, Faculté des sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | | | - Lucille Léonard
- Département de Génie Biologique, Université de Technologie de Compiègne, Compiègne, France
| | - Frédéric Grenier
- Département de biologie, Faculté des sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Sébastien Rodrigue
- Département de biologie, Faculté des sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Pascale B. Beauregard
- Département de biologie, Faculté des sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
| |
Collapse
|
5
|
Zhang N, Wang Z, Shao J, Xu Z, Liu Y, Xun W, Miao Y, Shen Q, Zhang R. Biocontrol mechanisms of Bacillus: Improving the efficiency of green agriculture. Microb Biotechnol 2023; 16:2250-2263. [PMID: 37837627 PMCID: PMC10686189 DOI: 10.1111/1751-7915.14348] [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: 08/21/2023] [Revised: 09/14/2023] [Accepted: 09/20/2023] [Indexed: 10/16/2023] Open
Abstract
Species of the genus Bacillus have been widely used for the biocontrol of plant diseases in the demand for sustainable agricultural development. New mechanisms underlying Bacillus biocontrol activity have been revealed with the development of microbiome and microbe-plant interaction research. In this review, we first briefly introduce the typical Bacillus biocontrol mechanisms, such as the production of antimicrobial compounds, competition for niches/nutrients, and induction of systemic resistance. Then, we discussed in detail the new mechanisms of pathogen quorum sensing interference and reshaping of the soil microbiota. The "cry for help" mechanism was also introduced, in which plants can release specific signals under pathogen attack to recruit biocontrol Bacillus for root colonization against invasion. Finally, two emerging strategies for enhancing the biocontrol efficacy of Bacillus agents, including the construction of synthetic microbial consortia and the application of rhizosphere-derived prebiotics, were proposed.
Collapse
Affiliation(s)
- Nan Zhang
- Jiangsu Provincial Key Lab of Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center of Solid Organic WastesNanjing Agricultural UniversityNanjingChina
| | - Zhengqi Wang
- Jiangsu Provincial Key Lab of Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center of Solid Organic WastesNanjing Agricultural UniversityNanjingChina
| | - Jiahui Shao
- Jiangsu Provincial Key Lab of Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center of Solid Organic WastesNanjing Agricultural UniversityNanjingChina
| | - Zhihui Xu
- Jiangsu Provincial Key Lab of Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center of Solid Organic WastesNanjing Agricultural UniversityNanjingChina
| | - Yunpeng Liu
- State Key Laboratory of Efficient Utilization of Arid and Semi‐arid Arable Land in Northern China, The Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural SciencesBeijingChina
| | - Weibing Xun
- Jiangsu Provincial Key Lab of Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center of Solid Organic WastesNanjing Agricultural UniversityNanjingChina
| | - Youzhi Miao
- Jiangsu Provincial Key Lab of Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center of Solid Organic WastesNanjing Agricultural UniversityNanjingChina
| | - Qirong Shen
- Jiangsu Provincial Key Lab of Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center of Solid Organic WastesNanjing Agricultural UniversityNanjingChina
| | - Ruifu Zhang
- Jiangsu Provincial Key Lab of Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center of Solid Organic WastesNanjing Agricultural UniversityNanjingChina
| |
Collapse
|
6
|
de Barros Dantas LL, Eldridge BM, Dorling J, Dekeya R, Lynch DA, Dodd AN. Circadian regulation of metabolism across photosynthetic organisms. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 116:650-668. [PMID: 37531328 PMCID: PMC10953457 DOI: 10.1111/tpj.16405] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 07/15/2023] [Accepted: 07/18/2023] [Indexed: 08/04/2023]
Abstract
Circadian regulation produces a biological measure of time within cells. The daily cycle in the availability of light for photosynthesis causes dramatic changes in biochemical processes in photosynthetic organisms, with the circadian clock having crucial roles in adaptation to these fluctuating conditions. Correct alignment between the circadian clock and environmental day-night cycles maximizes plant productivity through its regulation of metabolism. Therefore, the processes that integrate circadian regulation with metabolism are key to understanding how the circadian clock contributes to plant productivity. This forms an important part of exploiting knowledge of circadian regulation to enhance sustainable crop production. Here, we examine the roles of circadian regulation in metabolic processes in source and sink organ structures of Arabidopsis. We also evaluate possible roles for circadian regulation in root exudation processes that deposit carbon into the soil, and the nature of the rhythmic interactions between plants and their associated microbial communities. Finally, we examine shared and differing aspects of the circadian regulation of metabolism between Arabidopsis and other model photosynthetic organisms, and between circadian control of metabolism in photosynthetic and non-photosynthetic organisms. This synthesis identifies a variety of future research topics, including a focus on metabolic processes that underlie biotic interactions within ecosystems.
Collapse
Affiliation(s)
| | - Bethany M. Eldridge
- Department of Cell and Developmental BiologyJohn Innes Centre, Norwich Research ParkNorwichUK
| | - Jack Dorling
- Department of Cell and Developmental BiologyJohn Innes Centre, Norwich Research ParkNorwichUK
| | - Richard Dekeya
- Department of Cell and Developmental BiologyJohn Innes Centre, Norwich Research ParkNorwichUK
| | - Deirdre A. Lynch
- Department of Cell and Developmental BiologyJohn Innes Centre, Norwich Research ParkNorwichUK
| | - Antony N. Dodd
- Department of Cell and Developmental BiologyJohn Innes Centre, Norwich Research ParkNorwichUK
| |
Collapse
|
7
|
Mazoyon C, Firmin S, Bensaddek L, Pecourt A, Chabot A, Faucon MP, Sarazin V, Dubois F, Duclercq J. Optimizing Crop Production with Bacterial Inputs: Insights into Chemical Dialogue between Sphingomonas sediminicola and Pisum sativum. Microorganisms 2023; 11:1847. [PMID: 37513019 PMCID: PMC10385058 DOI: 10.3390/microorganisms11071847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/13/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
The use of biological inputs is an interesting approach to optimize crop production and reduce the use of chemical inputs. Understanding the chemical communication between bacteria and plants is critical to optimizing this approach. Recently, we have shown that Sphingomonas (S.) sediminicola can improve both nitrogen supply and yield in pea. Here, we used biochemical methods and untargeted metabolomics to investigate the chemical dialog between S. sediminicola and pea. We also evaluated the metabolic capacities of S. sediminicola by metabolic profiling. Our results showed that peas release a wide range of hexoses, organic acids, and amino acids during their development, which can generally recruit and select fast-growing organisms. In the presence of S. sediminicola, a more specific pattern of these molecules took place, gradually adapting to the metabolic capabilities of the bacterium, especially for pentoses and flavonoids. In turn, S. sediminicola is able to produce several compounds involved in cell differentiation, biofilm formation, and quorum sensing to shape its environment, as well as several molecules that stimulate pea growth and plant defense mechanisms.
Collapse
Affiliation(s)
- Candice Mazoyon
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR7058 CNRS), Université de Picardie Jules Verne (UPJV), 80039 Amiens, France
| | - Stéphane Firmin
- Agroécologie, Hydrogéochimie, Milieux et Ressources (AGHYLE, UP2018.C101) UniLaSalle, 60026 Beauvais, France
| | - Lamine Bensaddek
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR7058 CNRS), Université de Picardie Jules Verne (UPJV), 80039 Amiens, France
| | - Audrey Pecourt
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR7058 CNRS), Université de Picardie Jules Verne (UPJV), 80039 Amiens, France
- AgroStation, 68700 Aspach-le-Bas, France
| | - Amélie Chabot
- UFR des Sciences, Université de Picardie Jules Verne (UPJV), 80039 Amiens, France
| | - Michel-Pierre Faucon
- Agroécologie, Hydrogéochimie, Milieux et Ressources (AGHYLE, UP2018.C101) UniLaSalle, 60026 Beauvais, France
| | | | - Fréderic Dubois
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR7058 CNRS), Université de Picardie Jules Verne (UPJV), 80039 Amiens, France
| | - Jérôme Duclercq
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR7058 CNRS), Université de Picardie Jules Verne (UPJV), 80039 Amiens, France
| |
Collapse
|
8
|
Angelini LL, Dos Santos RAC, Fox G, Paruthiyil S, Gozzi K, Shemesh M, Chai Y. Pulcherrimin protects Bacillus subtilis against oxidative stress during biofilm development. NPJ Biofilms Microbiomes 2023; 9:50. [PMID: 37468524 PMCID: PMC10356805 DOI: 10.1038/s41522-023-00418-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Accepted: 07/04/2023] [Indexed: 07/21/2023] Open
Abstract
Pulcherrimin is an iron-binding reddish pigment produced by various bacterial and yeast species. In the soil bacterium Bacillus subtilis, this pigment is synthesized intracellularly as the colorless pulcherriminic acid by using two molecules of tRNA-charged leucine as the substrate; pulcherriminic acid molecules are then secreted and bind to ferric iron extracellularly to form the red-colored pigment pulcherrimin. The biological importance of pulcherrimin is not well understood. A previous study showed that secretion of pulcherrimin caused iron depletion in the surroundings and growth arrest on cells located at the edge of a B. subtilis colony biofilm. In this study, we identified that pulcherrimin is primarily produced under biofilm conditions and provides protection to cells in the biofilm against oxidative stress. We presented molecular evidence on how pulcherrimin lowers the level of reactive oxygen species (ROS) and alleviates oxidative stress and DNA damage caused by ROS accumulation in a mature biofilm. We also performed global transcriptome profiling to identify differentially expressed genes in the pulcherrimin-deficient mutant compared with the wild type, and further characterized the regulation of genes by pulcherrimin that are related to iron homeostasis, DNA damage response (DDR), and oxidative stress response. Based on our findings, we propose pulcherrimin as an important antioxidant that modulates B. subtilis biofilm development.
Collapse
Affiliation(s)
| | | | - Gabriel Fox
- Department of Biology, Northeastern University, Boston, MA, 02115, USA
| | - Srinand Paruthiyil
- Department of Biology, Northeastern University, Boston, MA, 02115, USA
- Medical Scientist Training Program (MSTP), Washington University School of Medicine, 660 S Euclid Ave, St. Louis, MO, 63110, USA
| | - Kevin Gozzi
- Department of Biology, Northeastern University, Boston, MA, 02115, USA
- The Rowland Institute at Harvard, 100 Edwin H. Land Blvd., Cambridge, MA, 02142, USA
| | - Moshe Shemesh
- Department of Food Science, Agricultural Research Organization The Volcani Institute, Derech Hamacabim, POB 15159, Rishon LeZion, 7528809, Israel
| | - Yunrong Chai
- Department of Biology, Northeastern University, Boston, MA, 02115, USA.
| |
Collapse
|
9
|
Gangwal A, Kumar N, Sangwan N, Dhasmana N, Dhawan U, Sajid A, Arora G, Singh Y. Giving a signal: how protein phosphorylation helps Bacillus navigate through different life stages. FEMS Microbiol Rev 2023; 47:fuad044. [PMID: 37533212 PMCID: PMC10465088 DOI: 10.1093/femsre/fuad044] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 07/30/2023] [Accepted: 08/01/2023] [Indexed: 08/04/2023] Open
Abstract
Protein phosphorylation is a universal mechanism regulating a wide range of cellular responses across all domains of life. The antagonistic activities of kinases and phosphatases can orchestrate the life cycle of an organism. The availability of bacterial genome sequences, particularly Bacillus species, followed by proteomics and functional studies have aided in the identification of putative protein kinases and protein phosphatases, and their downstream substrates. Several studies have established the role of phosphorylation in different physiological states of Bacillus species as they pass through various life stages such as sporulation, germination, and biofilm formation. The most common phosphorylation sites in Bacillus proteins are histidine, aspartate, tyrosine, serine, threonine, and arginine residues. Protein phosphorylation can alter protein activity, structural conformation, and protein-protein interactions, ultimately affecting the downstream pathways. In this review, we summarize the knowledge available in the field of Bacillus signaling, with a focus on the role of protein phosphorylation in its physiological processes.
Collapse
Affiliation(s)
- Aakriti Gangwal
- Department of Zoology, University of Delhi, Faculty of Science, Delhi- 110007, India
| | - Nishant Kumar
- Department of Zoology, University of Delhi, Faculty of Science, Delhi- 110007, India
| | - Nitika Sangwan
- Department of Zoology, University of Delhi, Faculty of Science, Delhi- 110007, India
- Department of Biomedical Science, Bhaskaracharya College of Applied Sciences, University of Delhi, New Delhi-110075, India
| | - Neha Dhasmana
- School of Medicine, New York University, 550 First Avenue New York-10016, New York, United States
| | - Uma Dhawan
- Department of Biomedical Science, Bhaskaracharya College of Applied Sciences, University of Delhi, New Delhi-110075, India
| | - Andaleeb Sajid
- 300 Cedar St, Yale School of Medicine, Yale University, New Haven, Connecticut 06520, New Haven CT, United States
| | - Gunjan Arora
- 300 Cedar St, Yale School of Medicine, Yale University, New Haven, Connecticut 06520, New Haven CT, United States
| | - Yogendra Singh
- Department of Zoology, University of Delhi, Faculty of Science, Delhi- 110007, India
- Delhi School of Public Health, Institution of Eminence, University of Delhi, Delhi-110007, India
| |
Collapse
|
10
|
Hu G, Wang Y, Blake C, Nordgaard M, Liu X, Wang B, Kovács ÁT. Parallel genetic adaptation of Bacillus subtilis to different plant species. Microb Genom 2023; 9:mgen001064. [PMID: 37466402 PMCID: PMC10438812 DOI: 10.1099/mgen.0.001064] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 06/16/2023] [Indexed: 07/20/2023] Open
Abstract
Plant growth-promoting rhizobacteria benefit plants by stimulating their growth or protecting them against phytopathogens. Rhizobacteria must colonize and persist on plant roots to exert their benefits. However, little is known regarding the processes by which rhizobacteria adapt to different plant species, or behave under alternating host plant regimes. Here, we used experimental evolution and whole-population whole-genome sequencing to analyse how Bacillus subtilis evolves on Arabidopsis thaliana and tomato seedlings, and under an alternating host plant regime, in a static hydroponic setup. We observed parallel evolution across multiple levels of biological organization in all conditions, which was greatest for the two heterogeneous, multi-resource, spatially structured environments at the genetic level. Species-specific adaptation at the genetic level was also observed, possibly caused by the selection stress imposed by different host plants. Furthermore, a trade-off between motility and biofilm development was supported by mutational changes in motility- and biofilm-related genes. Finally, we identified several condition-specific and common targeted genes in different environments by comparing three different B. subtilis biofilm adaptation settings. The results demonstrate a common evolutionary pattern when B. subtilis is adapting to the plant rhizosphere in similar conditions, and reveal differences in genetic mechanisms between different host plants. These findings will likely support strain improvements for sustainable agriculture.
Collapse
Affiliation(s)
- Guohai Hu
- China National GeneBank, BGI-Shenzhen, Shenzhen 518120, PR China
- BGI-Shenzhen, Shenzhen 518083, PR China
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Yue Wang
- China National GeneBank, BGI-Shenzhen, Shenzhen 518120, PR China
- BGI-Shenzhen, Shenzhen 518083, PR China
- BGI-Beijing, Beijing 102601, PR China
| | - Christopher Blake
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Mathilde Nordgaard
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Xin Liu
- China National GeneBank, BGI-Shenzhen, Shenzhen 518120, PR China
- BGI-Shenzhen, Shenzhen 518083, PR China
- BGI-Beijing, Beijing 102601, PR China
| | - Bo Wang
- China National GeneBank, BGI-Shenzhen, Shenzhen 518120, PR China
- BGI-Shenzhen, Shenzhen 518083, PR China
- Shenzhen Key Laboratory of Environmental Microbial Genomics and Application, BGI Shenzhen, 518083 Shenzhen, PR China
| | - Ákos T. Kovács
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Lyngby, Denmark
- Institute of Biology Leiden, Leiden University, 2333BE Leiden, Netherlands
| |
Collapse
|
11
|
Gao T, Wang X, Qin Y, Ren Z, Zhao X. Watermelon Root Exudates Enhance Root Colonization of Bacillus amyloliquefaciens TR2. Curr Microbiol 2023; 80:110. [PMID: 36802037 DOI: 10.1007/s00284-023-03206-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 01/30/2023] [Indexed: 02/21/2023]
Abstract
Bacillus amyloliquefaciens TR2, one of plant growth-promoting rhizobacteria (PGPR), is capable of colonizing plant roots in a large population size. However, the interaction of watermelon root exudates and colonization of the strain TR2 has not yet been clearly elucidated. In this investigation, we demonstrated that B. amyloliquefaciens TR2 promoted watermelon plants growth and exhibited biocontrol efficacy against watermelon Fusarium wilt under greenhouse conditions. Collected watermelon root exudates significantly induced chemotaxis, swarming motility, and biofilm formation of the strain TR2. We also tested the components of root exudates (organic acids: malic acid, citric acid, succinic acid, and fumaric acid; amino acids: methionine, glutamic acid, alanine, and aspartic acid; phenolic acid: benzoic acid) and the results showed that a majority of these compounds could promote chemotactic response, swarming motility, and biofilm formation in a different degree. Benzoic acid induced the strongest chemotactic response; however, the swarming motility and biofilm formation of the strain TR2 were maximumly enhanced by supplement of fumaric acid and glutamic acid, respectively. In addition, the root colonization examination indicated that the population of B. amyloliquefaciens TR2 colonized on watermelon root surfaces was dramatically increased by adding concentrated watermelon root exudates. In summary, our studies provide evidence suggesting that root exudates are important for colonization of B. amyloliquefaciens TR2 on plant roots and help us to understand the interaction between plants and beneficial bacteria.
Collapse
Affiliation(s)
- Tantan Gao
- Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, No.7 Beinong Road, Huilongguan District, Beijing, 102206, China
| | - Xudong Wang
- Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, No.7 Beinong Road, Huilongguan District, Beijing, 102206, China
| | - Yanqiu Qin
- Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, No.7 Beinong Road, Huilongguan District, Beijing, 102206, China
| | - Zhengguang Ren
- Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, No.7 Beinong Road, Huilongguan District, Beijing, 102206, China
| | - Xiaoyan Zhao
- Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, No.7 Beinong Road, Huilongguan District, Beijing, 102206, China.
| |
Collapse
|
12
|
Jiao H, Xu W, Hu Y, Tian R, Wang Z. Citric Acid in Rice Root Exudates Enhanced the Colonization and Plant Growth-Promoting Ability of Bacillus altitudinis LZP02. Microbiol Spectr 2022; 10:e0100222. [PMID: 36264248 PMCID: PMC9769925 DOI: 10.1128/spectrum.01002-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 09/24/2022] [Indexed: 01/05/2023] Open
Abstract
Exploration of the underlying mechanisms of plant-microbe interactions is very important. In the present study, citric acid in the root exudates of rice significantly enhanced the colonization of Bacillus altitudinis LZP02 in the rhizosphere. According to the results of transcriptome and reverse transcription-quantitative PCR or analyses, citric acid increased the expression of several genes involved in bacterial chemotaxis and biofilm formation in B. altitudinis LZP02. In addition, citric acid also increased the expression of several genes associated with S-adenosylmethionine biosynthesis and metabolism. Interestingly, the secretion of citric acid by rice roots could be increased by inoculation with B. altitudinis LZP02. The result indicated that citric acid might be a vital signal in the interaction between rice and B. altitudinis LZP02. Further verification showed that citric acid enhanced the plant growth-promoting ability of B. altitudinis LZP02. IMPORTANCE In a previous study, the mechanism by which citric acid in rice root exudates enhanced the colonization of Bacillus altitudinis LZP02 was discovered. The present study verified that citric acid increased the recruitment and rice growth-promoting ability of B. altitudinis LZP02. These findings serve as an interesting case for explaining the underlying mechanisms of plant-microbe interactions. Henceforth, citric acid and B. altitudinis LZP02 could be exploited for the development of sustainable agronomy.
Collapse
Affiliation(s)
- Huiwen Jiao
- School of Life Science and Agriculture Forestry, Qiqihar University, Qiqihar, Heilongjiang, China
- Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, China
| | - Weihui Xu
- School of Life Science and Agriculture Forestry, Qiqihar University, Qiqihar, Heilongjiang, China
- Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, China
| | - Yunlong Hu
- School of Life Science and Agriculture Forestry, Qiqihar University, Qiqihar, Heilongjiang, China
- Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, China
| | - Renmao Tian
- Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, Illinois, USA
| | - Zhigang Wang
- School of Life Science and Agriculture Forestry, Qiqihar University, Qiqihar, Heilongjiang, China
- Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, China
| |
Collapse
|
13
|
Khan AR, Mustafa A, Hyder S, Valipour M, Rizvi ZF, Gondal AS, Yousuf Z, Iqbal R, Daraz U. Bacillus spp. as Bioagents: Uses and Application for Sustainable Agriculture. BIOLOGY 2022; 11:biology11121763. [PMID: 36552272 PMCID: PMC9775066 DOI: 10.3390/biology11121763] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 11/28/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022]
Abstract
Food security will be a substantial issue in the near future due to the expeditiously growing global population. The current trend in the agriculture industry entails the extravagant use of synthesized pesticides and fertilizers, making sustainability a difficult challenge. Land degradation, lower production, and vulnerability to both abiotic and biotic stresses are problems caused by the usage of these pesticides and fertilizers. The major goal of sustainable agriculture is to ameliorate productivity and reduce pests and disease prevalence to such a degree that prevents large-scale damage to crops. Agriculture is a composite interrelation among plants, microbes, and soil. Plant microbes play a major role in growth promotion and improve soil fertility as well. Bacillus spp. produces an extensive range of bio-chemicals that assist in plant disease control, promote plant development, and make them suitable for agricultural uses. Bacillus spp. support plant growth by N fixation, P and K solubilization, and phytohormone synthesis, in addition to being the most propitious biocontrol agent. Moreover, Bacilli excrete extracellular metabolites, including antibiotics, lytic enzymes, and siderophores, and demonstrate antagonistic activity against phytopathogens. Bacillus spp. boosts plant resistance toward pathogens by inducing systemic resistance (ISR). The most effective microbial insecticide against insects and pests in agriculture is Bacillus thuringiensis (Bt). Additionally, the incorporation of toxin genes in genetically modified crops increases resistance to insects and pests. There is a constant increase in the identified Bacillus species as potential biocontrol agents. Moreover, they have been involved in the biosynthesis of metallic nanoparticles. The main objective of this review article is to display the uses and application of Bacillus specie as a promising biopesticide in sustainable agriculture. Bacillus spp. strains that are antagonistic and promote plant yield attributes could be valuable in developing novel formulations to lead the way toward sustainable agriculture.
Collapse
Affiliation(s)
- Aimen Razzaq Khan
- Department of Botany, Government College Women University Sialkot, Sialkot 51310, Pakistan
| | - Adeena Mustafa
- Department of Botany, Government College Women University Sialkot, Sialkot 51310, Pakistan
| | - Sajjad Hyder
- Department of Botany, Government College Women University Sialkot, Sialkot 51310, Pakistan
- Correspondence: (S.H.); (M.V.)
| | - Mohammad Valipour
- Department of Engineering and Engineering Technology, Metropolitan State University of Denver, Denver, CO 80217, USA
- Correspondence: (S.H.); (M.V.)
| | - Zarrin Fatima Rizvi
- Department of Botany, Government College Women University Sialkot, Sialkot 51310, Pakistan
| | - Amjad Shahzad Gondal
- Department of Plant Pathology, Bahauddin Zakariya University Multan, Multan 60000, Pakistan
| | - Zubaida Yousuf
- Department of Botany, Lahore College for Women University, Lahore 54000, Pakistan
| | - Rashid Iqbal
- Department of Agronomy, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan
| | - Umar Daraz
- State Key Laboratory of Grassland Agroecosystem, Center for Grassland Microbiome, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China
| |
Collapse
|
14
|
Biosynthesis of gold nanoparticles and inhibition of various stages of bacterial biofilms formed by drug-resistant Aeromonas hydrophila, Escherichia coli, and Klebsiella pneumoniae. Arch Microbiol 2022; 204:719. [DOI: 10.1007/s00203-022-03325-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 11/02/2022] [Accepted: 11/07/2022] [Indexed: 11/21/2022]
|
15
|
Böhning J, Ghrayeb M, Pedebos C, Abbas DK, Khalid S, Chai L, Bharat TAM. Donor-strand exchange drives assembly of the TasA scaffold in Bacillus subtilis biofilms. Nat Commun 2022; 13:7082. [PMID: 36400765 PMCID: PMC9674648 DOI: 10.1038/s41467-022-34700-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 11/03/2022] [Indexed: 11/19/2022] Open
Abstract
Many bacteria in nature exist in multicellular communities termed biofilms, where cells are embedded in an extracellular matrix that provides rigidity to the biofilm and protects cells from chemical and mechanical stresses. In the Gram-positive model bacterium Bacillus subtilis, TasA is the major protein component of the biofilm matrix, where it has been reported to form functional amyloid fibres contributing to biofilm structure and stability. Here, we present electron cryomicroscopy structures of TasA fibres, which show that, rather than forming amyloid fibrils, TasA monomers assemble into fibres through donor-strand exchange, with each subunit donating a β-strand to complete the fold of the next subunit along the fibre. Combining electron cryotomography, atomic force microscopy, and mutational studies, we show how TasA fibres congregate in three dimensions to form abundant fibre bundles that are essential for B. subtilis biofilm formation. Our study explains the previously observed biochemical properties of TasA and shows how a bacterial extracellular globular protein can assemble from monomers into β-sheet-rich fibres, and how such fibres assemble into bundles in biofilms.
Collapse
Affiliation(s)
- Jan Böhning
- grid.4991.50000 0004 1936 8948Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE UK
| | - Mnar Ghrayeb
- grid.9619.70000 0004 1937 0538Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, 91904 Israel ,grid.9619.70000 0004 1937 0538The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, 91904 Israel
| | - Conrado Pedebos
- grid.4991.50000 0004 1936 8948Department of Biochemistry, University of Oxford, Oxford, OX1 3QU UK
| | - Daniel K. Abbas
- grid.4991.50000 0004 1936 8948Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE UK
| | - Syma Khalid
- grid.4991.50000 0004 1936 8948Department of Biochemistry, University of Oxford, Oxford, OX1 3QU UK
| | - Liraz Chai
- Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, 91904, Israel. .,The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, 91904, Israel.
| | - Tanmay A. M. Bharat
- grid.4991.50000 0004 1936 8948Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE UK ,grid.42475.300000 0004 0605 769XStructural Studies Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH UK
| |
Collapse
|
16
|
Boyeldieu A, Poli J, Ali Chaouche A, Fierobe H, Giudici‐Orticoni M, Méjean V, Jourlin‐Castelli C. Multiple detection of both attractants and repellents by the dCache-chemoreceptor SO_1056 of Shewanella oneidensis. FEBS J 2022; 289:6752-6766. [PMID: 35668695 PMCID: PMC9796306 DOI: 10.1111/febs.16548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 05/17/2022] [Accepted: 06/06/2022] [Indexed: 01/01/2023]
Abstract
Chemoreceptors are usually transmembrane proteins dedicated to the detection of compound gradients or signals in the surroundings of a bacterium. After detection, they modulate the activation of CheA-CheY, the core of the chemotactic pathway, to allow cells to move upwards or downwards depending on whether the signal is an attractant or a repellent, respectively. Environmental bacteria such as Shewanella oneidensis harbour dozens of chemoreceptors or MCPs (methyl-accepting chemotaxis proteins). A recent study revealed that MCP SO_1056 of S. oneidensis binds chromate. Here, we show that this MCP also detects an additional attractant (l-malate) and two repellents (nickel and cobalt). The experiments were performed in vivo by the agarose-in-plug technique after overproducing MCP SO_1056 and in vitro, when possible, by submitting the purified ligand-binding domain (LBD) of SO_1056 to a thermal shift assay (TSA) coupled to isothermal titration calorimetry (ITC). ITC assays revealed a KD of 3.4 μm for l-malate and of 47.7 μm for nickel. We conclude that MCP SO_1056 binds attractants and repellents of unrelated composition. The LBD of SO_1056 belongs to the double Cache_1 family and is highly homologous to PctA, a chemoreceptor from Pseudomonas aeruginosa that detects several amino acids. Therefore, LBDs of the same family can bind diverse compounds, confirming that experimental approaches are required to define accurate LBD-binding molecules or signals.
Collapse
Affiliation(s)
- Anne Boyeldieu
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance,Present address:
Laboratoire de Microbiologie et de Génétique Moléculaires, UMR5100, Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS)Université de Toulouse, UPSFrance
| | - Jean‐Pierre Poli
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance,Université de Corse Pasquale PaoliCorteFrance
| | - Amine Ali Chaouche
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance
| | - Henri‐Pierre Fierobe
- Laboratoire de Chimie Bactérienne (LCB, UMR7283), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance
| | - Marie‐Thérèse Giudici‐Orticoni
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance
| | - Vincent Méjean
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance
| | - Cécile Jourlin‐Castelli
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance
| |
Collapse
|
17
|
Yang W, Yan H, Dong G, Li Z, Jiang C, Gu D, Niu D, Zhou D, Luo Y. Comparative transcriptomics reveal different genetic adaptations of biofilm formation in Bacillus subtilis isolate 1JN2 in response to Cd2+ treatment. Front Microbiol 2022; 13:1002482. [PMID: 36267191 PMCID: PMC9577173 DOI: 10.3389/fmicb.2022.1002482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/05/2022] [Indexed: 12/01/2022] Open
Abstract
Biofilm plays important roles in the life cycle of Bacillus species, such as promoting host and object surface colonization and resisting heavy metal stress. This study utilized transcriptomics to evaluate the impacts of cadmium on the components, morphology, and function of biofilms of Bacillus subtilis strain 1JN2. Under cadmium ion stress, the morphology of the B. subtilis 1JN2 biofilm was flattened, and its mobility increased. Moreover, differential gene expression analysis showed that the main regulator of biofilm formation, Spo0A, decreased in expression under cadmium ion stress, thereby inhibiting extracellular polysaccharide synthesis through the SinI/SinR two-component regulatory system and the AbrB pathway. Cadmium ion treatment also increased the SigD content significantly, thereby increasing the expression of the flagella encoding and assembly genes in the strain. This promoted poly-γ-glutamic acid production via the DegS/DegU two-component regulatory system and the conversion of biofilm extracellular polysaccharide to poly-γ-glutamic acid. This conferred cadmium stress tolerance in the strain. Additionally, the cadmium ion-mediated changes in the biofilm composition affected the colonization of the strain on the host plant root surface. Cadmium ions also induced surfactin synthesis. These findings illustrate the potential of Bacillus species as biocontrol strains that can mitigate plant pathogenic infections and heavy metal stress. The results also provide a basis for the screening of multifunctional biocontrol strains.
Collapse
Affiliation(s)
- Wei Yang
- Jiangsu Key Laboratory for Eco-Agricultural Biotechnology Around Hongze Lake, School of Life Science, Huaiyin Normal University, Huai’an, China
- Jiangsu Collaborative Innovation Center of Regional Modern Agriculture & Environmental Protection, Huai’an, China
| | - Haixia Yan
- Agro-Tech Extension and Service Center, Huai’an, China
| | - Guanghui Dong
- Jiangsu Key Laboratory for Eco-Agricultural Biotechnology Around Hongze Lake, School of Life Science, Huaiyin Normal University, Huai’an, China
| | - Zhengpeng Li
- Jiangsu Key Laboratory for Eco-Agricultural Biotechnology Around Hongze Lake, School of Life Science, Huaiyin Normal University, Huai’an, China
- Jiangsu Collaborative Innovation Center of Regional Modern Agriculture & Environmental Protection, Huai’an, China
| | - Chunhao Jiang
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Dalu Gu
- Huaiyin Institute of Agricultural Sciences of Xuhuai Region in Jiangsu, Huaian Academy of Agricultural Sciences, Huai’an, China
| | - Dongdong Niu
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Danni Zhou
- Jiangsu Key Laboratory for Eco-Agricultural Biotechnology Around Hongze Lake, School of Life Science, Huaiyin Normal University, Huai’an, China
| | - Yuming Luo
- Jiangsu Key Laboratory for Eco-Agricultural Biotechnology Around Hongze Lake, School of Life Science, Huaiyin Normal University, Huai’an, China
- Jiangsu Collaborative Innovation Center of Regional Modern Agriculture & Environmental Protection, Huai’an, China
- *Correspondence: Yuming Luo,
| |
Collapse
|
18
|
Kin Discrimination Modifies Strain Distribution, Spatial Segregation, and Incorporation of Extracellular Matrix Polysaccharide Mutants of Bacillus subtilis Strains into Mixed Floating Biofilms. Appl Environ Microbiol 2022; 88:e0087122. [PMID: 36094206 PMCID: PMC9499035 DOI: 10.1128/aem.00871-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microorganisms in nature form multicellular groups called biofilms. In biofilms, bacteria embedded in the extracellular matrix (ECM) interact intensely due to their proximity. Most studies have investigated genetically homogeneous biofilms, leaving a gap in knowledge on genetically heterogeneous biofilms. Recent insights show that a Gram-positive model bacterium, Bacillus subtilis, discriminates between strains of high (kin) and low (nonkin) genetic similarity, reflected in merging (kin) and boundaries (nonkin) between swarms. However, it is unclear how kinship between interacting strains affects their fitness, the genotype assortment, and incorporation of the mutant lacking the main structural ECM polysaccharide (EpsA-O) into floating biofilms (pellicles). We cultivated Bacillus subtilis strains as mixtures of isogenic, kin, and nonkin strain combinations in the biofilm-promoting minimal medium under static conditions, allowing them to form pellicles. We show that in nonkin pellicles, the dominant strain strongly reduced the frequency of the other strain. Segregation of nonkin mixtures in pellicles increased and invasion of nonkin EpsA-O-deficient mutants into pellicles decreased compared to kin and isogenic floating biofilms. Kin and isogenic strains had comparable relative frequencies in pellicles and showed more homogenous cell mixing. Overall, our results emphasize kin discrimination as a social behavior that shapes strain distribution, spatial segregation, and ECM mutant ability to incorporate into genetically heterogenous biofilms of B. subtilis. IMPORTANCE Biofilm communities have beneficial and harmful effects on human societies in natural, medical, and industrial environments. Bacillus subtilis is a biotechnologically important bacterium that serves as a model for studying biofilms. Recent studies have shown that this species engages in kin discriminatory behavior during swarming, which may have implications for community assembly, thus being of fundamental importance. Effects of kin discrimination on fitness, genotype segregation, and success of extracellular matrix (ECM) polysaccharide (EpsA-O) mutant invasion into biofilms are not well understood. We provide evidence that kin discrimination depends on the antagonism of the dominant strain against nonkin by using environmental strains with determined kin types and integrated fluorescent reporters. Moreover, this antagonism has important implications for genotype segregation and for when the bacteria are mixed with ECM producers. The work advances the understanding of kin-discrimination-dependent bacterial sociality in biofilms and its role in the assembly of multicellular groups.
Collapse
|
19
|
Nie LJ, Ye WQ, Xie WY, Zhou WW. Biofilm: New insights in the biological control of fruits with Bacillus amyloliquefaciens B4. Microbiol Res 2022; 265:127196. [PMID: 36116146 DOI: 10.1016/j.micres.2022.127196] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 08/07/2022] [Accepted: 09/09/2022] [Indexed: 10/14/2022]
Abstract
Biofilms are sessile microbial communities growing on surfaces, which are encased in some self-produced extracellular material. Beneficial biofilm could be widely used in agriculture, food, medicine, environment and other fields. As an ideal biocontrol agent, Bacillus amyloliquefaciens B4 can form a strong biofilm under static conditions. In this study, we screened out metal compounds that enhanced or inhibited the biofilm formation ability of B4, established the relationship between the biofilm of B4 strain and its postharvest biocontrol effect, and explored the regulation of metal compounds on the biofilm formation. The results showed 0.5 mmol L-1 ferric chloride could enhance the biofilm formation and strengthen the antifungal effect of B4, indicating that there was a positive relationship between the growth of biofilm and its biocontrol effect. The enhanced biofilm had a certain biocontrol effect on different fruit, including peach, loquat, Kyoho grape and cherry tomato. Furthermore, the expression of degU and tasA was affected by metal ion treatment, which meant the genes might be essential for the biofilm formation of B4. Our findings suggested that biofilm of B. amyloliquefaciens played an essential role in the process of biocontrol and it might be a novel strategy for managing postharvest fruit decay.
Collapse
Affiliation(s)
- Lin-Jie Nie
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Wan-Qiong Ye
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Wan-Yue Xie
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Wen-Wen Zhou
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou 310058, Zhejiang, China.
| |
Collapse
|
20
|
Korenblum E, Massalha H, Aharoni A. Plant-microbe interactions in the rhizosphere via a circular metabolic economy. THE PLANT CELL 2022; 34:3168-3182. [PMID: 35678568 PMCID: PMC9421461 DOI: 10.1093/plcell/koac163] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 04/25/2022] [Indexed: 05/30/2023]
Abstract
Chemical exchange often serves as the first step in plant-microbe interactions and exchanges of various signals, nutrients, and metabolites continue throughout the interaction. Here, we highlight the role of metabolite exchanges and metabolic crosstalk in the microbiome-root-shoot-environment nexus. Roots secret a diverse set of metabolites; this assortment of root exudates, including secondary metabolites such as benzoxazinoids, coumarins, flavonoids, indolic compounds, and terpenes, shapes the rhizosphere microbiome. In turn, the rhizosphere microbiome affects plant growth and defense. These inter-kingdom chemical interactions are based on a metabolic circular economy, a seemingly wasteless system in which rhizosphere members exchange (i.e. consume, reuse, and redesign) metabolites. This review also describes the recently discovered phenomenon "Systemically Induced Root Exudation of Metabolites" in which the rhizosphere microbiome governs plant metabolism by inducing systemic responses that shift the metabolic profiles of root exudates. Metabolic exchange in the rhizosphere is based on chemical gradients that form specific microhabitats for microbial colonization and we describe recently developed high-resolution methods to study chemical interactions in the rhizosphere. Finally, we propose an action plan to advance the metabolic circular economy in the rhizosphere for sustainable solutions to the cumulative degradation of soil health in agricultural lands.
Collapse
Affiliation(s)
| | - Hassan Massalha
- Theory of Condensed Matter Group, Cavendish Laboratory, Wellcome Sanger Institute, University of Cambridge, Cambridge CB2 1TN, UK
| | - Asaph Aharoni
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| |
Collapse
|
21
|
Chen Y, Kolodkin-Gal I. Host-Biofilm Interactions. Microorganisms 2022; 10:microorganisms10081641. [PMID: 36014059 PMCID: PMC9416182 DOI: 10.3390/microorganisms10081641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 08/10/2022] [Indexed: 11/16/2022] Open
Affiliation(s)
- Yun Chen
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Ilana Kolodkin-Gal
- Department of Plant Pathology and Microbiology, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
- Correspondence:
| |
Collapse
|
22
|
Xue J, Tong T, Wang R, Qiu Y, Gu Y, Sun L, Xu H, Lei P. Secretion of poly-γ-glutamic acid by Bacillus atrophaeus NX-12 enhanced its root colonization and biocontrol activity. Front Microbiol 2022; 13:972393. [PMID: 35966665 PMCID: PMC9372288 DOI: 10.3389/fmicb.2022.972393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 07/04/2022] [Indexed: 11/22/2022] Open
Abstract
Bacilli are used as biocontrol agents (BCAs) against phytopathogens and most of them can produce poly-γ-glutamic acid (γ-PGA) as one of the major extracellular polymeric substances (EPSs). However, the role of γ-PGA in plant biocontrol is still unclear. In this study, Bacillus atrophaeus NX-12 (γ-PGA yield: 16.8 g/l) was screened, which formed a strong biofilm and has been proved to be a promising BCA against Cucumber Fusarium wilt. Then, the γ-PGA synthesis gene cluster pgsBCA was knocked out by CRISPR-Cas9n. Interestingly, the antifungal ability of γ-PGA synthetase-deficient strain NX-12Δpgs (γ-PGA yield: 1.65 g/l) was improved in vitro, while the biocontrol ability of NX-12Δpgs was greatly diminished in situ. Data proved that γ-PGA produced by NX-12 contributes to the biofilm formation and rhizosphere colonization, which effectively improved biocontrol capability. Taken together, these findings prove that the mechanism of γ-PGA promotes the colonization of NX-12 and thus assists in controlling plant diseases, which highlight the key role of γ-PGA produced by BCA in biocontrol.
Collapse
|
23
|
Xu S, Cao Q, Liu Z, Chen J, Yan P, Li B, Xu Y. Transcriptomic Analysis Reveals the Role of tmRNA on Biofilm Formation in Bacillus subtilis. Microorganisms 2022; 10:microorganisms10071338. [PMID: 35889057 PMCID: PMC9319509 DOI: 10.3390/microorganisms10071338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 06/30/2022] [Accepted: 06/30/2022] [Indexed: 11/16/2022] Open
Abstract
Bacillus strains are widely distributed in terrestrial and marine environments, and some of them are used as biocontrol organisms for their biofilm-formation ability. In Bacillus subtilis, biofilm formation is fine-tuned by a complex network, a clear understanding of which still requires study. In bacteria, tmRNA, encoded by the ssrA gene, catalyzes trans-translation that can rescue ribosomes stalled on mRNA transcripts lacking a functional stop codon. tmRNA also affects physiological bioprocesses in some bacteria. In this study, we constructed a ssrA mutant in B. subtilis and found that the biofilm formation in the ssrA mutant was largely impaired. Moreover, we isolated a biofilm-formation suppressor of ssrA, in which the biofilm formation was restored to a level even stronger than that in the wild type. We further performed RNAseq assays with the wild type, ssrA mutant, and suppressor of ssrA for comparisons of their transcriptomes. By analyzing the transcriptomic data, we predicted the possible functions of some differentially expressed genes (DEGs) in the tmRNA regulation of biofilm formation in B. subtilis. Finally, we found that the overexpression of two DEGs, acoA and yhjR, could restore the biofilm formation in the ssrA mutant, indicating that AcoA and YhjR were immediate regulators involved in the tmRNA regulatory web controlling biofilm formation in B. subtilis. Our data can improve the knowledge about the molecular network involved in Bacillus biofilm formation and provide new targets for manipulation of Bacillus biofilms for future investigation.
Collapse
Affiliation(s)
- Shanshan Xu
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518055, China; (S.X.); (Q.C.); (Z.L.); (J.C.)
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China;
| | - Qianqian Cao
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518055, China; (S.X.); (Q.C.); (Z.L.); (J.C.)
| | - Zengzhi Liu
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518055, China; (S.X.); (Q.C.); (Z.L.); (J.C.)
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China;
| | - Junpeng Chen
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518055, China; (S.X.); (Q.C.); (Z.L.); (J.C.)
| | - Peiguang Yan
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China;
| | - Bingyu Li
- Guangdong Key Laboratory for Genome Stability and Disease Prevention, Health Science Center, Shenzhen University, Shenzhen 518055, China
- Correspondence: (B.L.); (Y.X.)
| | - Ying Xu
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518055, China; (S.X.); (Q.C.); (Z.L.); (J.C.)
- Correspondence: (B.L.); (Y.X.)
| |
Collapse
|
24
|
Nordgaard M, Blake C, Maróti G, Hu G, Wang Y, Strube ML, Kovács ÁT. Experimental evolution of Bacillus subtilis on Arabidopsis thaliana roots reveals fast adaptation and improved root colonization. iScience 2022; 25:104406. [PMID: 35663012 PMCID: PMC9157203 DOI: 10.1016/j.isci.2022.104406] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 01/22/2022] [Accepted: 05/05/2022] [Indexed: 12/16/2022] Open
Abstract
Bacillus subtilis is known to promote plant growth and protect plants against disease. B. subtilis rapidly adapts to Arabidopsis thaliana root colonization, as evidenced by improved root colonizers already after 12 consecutive transfers between seedlings in a hydroponic setup. Re-sequencing of single evolved isolates and endpoint populations revealed mutations in genes related to different bacterial traits, in accordance with evolved isolates displaying increased root colonization associated with robust biofilm formation in response to the plant polysaccharide xylan and impaired motility. Interestingly, evolved isolates suffered a fitness disadvantage in a non-selective environment, demonstrating an evolutionary cost of adaptation to the plant root. Finally, increased root colonization by an evolved isolate was also demonstrated in the presence of resident soil microbes. Our findings highlight how a plant growth-promoting rhizobacterium rapidly adapts to an ecologically relevant environment and reveal evolutionary consequences that are fundamental to consider when evolving strains for biocontrol purposes. Bacillus subtilis shows fast adaptation to Arabidopsis thaliana roots in a hydroponic setup Evolved isolates exhibit robust biofilms in response to xylan and impaired motility Adaptation to A. thaliana roots is accompanied by an evolutionary cost An evolved isolate shows higher root colonization in the presence of soil bacteria
Collapse
Affiliation(s)
- Mathilde Nordgaard
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Christopher Blake
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Gergely Maróti
- Institute of Plant Biology, Biological Research Centre, Eötvös Loránd Research Network (ELKH), 6726 Szeged, Hungary
| | - Guohai Hu
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.,China National GeneBank, BGI-Shenzhen, 518120 Shenzhen, China
| | - Yue Wang
- China National GeneBank, BGI-Shenzhen, 518120 Shenzhen, China.,BGI-Beijing, BGI-Shenzhen, 100101 Beijing, China
| | - Mikael Lenz Strube
- Bacterial Ecophysiology and Biotechnology Group, DTU Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Ákos T Kovács
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| |
Collapse
|
25
|
Xie L, Timonen S, Gange AC, Kuoppamäki K, Hagner M, Lehvävirta S. Effect of weather conditions, substrate pH, biochar amendment and plant species on two plant growth-promoting microbes on vegetated roofs and facades. Heliyon 2022; 8:e09560. [PMID: 35677418 PMCID: PMC9167976 DOI: 10.1016/j.heliyon.2022.e09560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 04/19/2022] [Accepted: 05/24/2022] [Indexed: 11/27/2022] Open
Abstract
Background Vegetated building envelopes (VBEs), such as vegetated roofs and facades, are becoming more frequent in urban planning nowadays. However, harsh growing conditions restrain the application of VBEs. Plant growth-promoting microbes (PGPMs) might help ease the stresses, but first, it is necessary to investigate how to ensure their survival and growth under VBE conditions. Methods We conducted three experiments to test the impact of various factors on the microbial populations of inoculated PGPMs in VBEs, a mycorrhizal fungus Rhizophagus irregularis and a bacterium Bacillus amyloliquefaciens. The first experiment was conducted by inoculating the two PGPMs separately in Sedum roof plots, and the microbial populations associated with Poa alpina was monitored for two consecutive years under local weather conditions. The second experiment was conducted in a laboratory testing the effect of substrate pH (substrates collected from balcony gardens) on R. irregularis population associated with Trifolium repens and Viola tricolor. The third experiment was conducted on a meadow roof testing the effect of biochar amendment on R. irregularis population associated with Thymus serpyllum and Fragaria vesca. Results In the first experiment, Bacillus was found to associate with P. alpina, but Rhizophagus wasn't. Yet, the fungus induced high Bacillus population density in the Rhizophagus treated plots in the first year. In the second experiment, Rhizophagus abundance in T. repens was higher in the neutral substrate (6–6.5), while V. tricolor was more colonized in acidic substrate (5–5.5), suggesting an important interactive effect of substrate pH and plant species on Rhizophagus abundance. The third experiment suggested a negligible impact of biochar amendment on Rhizophagus abundance for both host plants. Conclusion Three experiments demonstrate that PGPM inoculation on VBEs is feasible, and various factors and interactions affect the PGPM populations. This paper provides reference and inspiration for other VBE research involving substrate microbial manipulation.
Collapse
Affiliation(s)
- Long Xie
- Department of Agricultural Sciences, University of Helsinki, PO Box 27, FI-00014, Finland
| | - Sari Timonen
- Department of Microbiology, University of Helsinki, PO Box 56, FI-00014, Finland
| | - Alan C Gange
- Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK
| | - Kirsi Kuoppamäki
- Ecosystems and Environment Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, FI-15140, Lahti, Finland
| | - Marleena Hagner
- Natural Resources Institute Finland (Luke), FI-31600, Jokioinen, Finland
| | - Susanna Lehvävirta
- Ecosystems and Environment Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, PO Box 65, FI-00014, Finland
| |
Collapse
|
26
|
Qin Y, Angelini LL, Chai Y. Bacillus subtilis Cell Differentiation, Biofilm Formation and Environmental Prevalence. Microorganisms 2022; 10:microorganisms10061108. [PMID: 35744626 PMCID: PMC9227780 DOI: 10.3390/microorganisms10061108] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/20/2022] [Accepted: 05/24/2022] [Indexed: 11/26/2022] Open
Abstract
Bacillus subtilis is a soil-dwelling, spore-forming Gram-positive bacterium capable of cell differentiation. For decades, B. subtilis has been used as a model organism to study development of specialized cell types. In this minireview, we discuss cell differentiation in B. subtilis, covering both past research and recent progresses, and the role of cell differentiation in biofilm formation and prevalence of this bacterium in the environment. We review B. subtilis as a classic model for studies of endospore formation, and highlight more recent investigations on cell fate determination and generation of multiple cell types during biofilm formation. We present mechanistic details of how cell fate determination and mutually exclusive cell differentiation are regulated during biofilm formation.
Collapse
Affiliation(s)
- Yuxuan Qin
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Correspondence: (Y.Q.); (Y.C.)
| | | | - Yunrong Chai
- Department of Biology, Northeastern University, Boston, MA 02115, USA;
- Correspondence: (Y.Q.); (Y.C.)
| |
Collapse
|
27
|
Si P, Shao W, Yu H, Xu G, Du G. Differences in Microbial Communities Stimulated by Malic Acid Have the Potential to Improve Nutrient Absorption and Fruit Quality of Grapes. Front Microbiol 2022; 13:850807. [PMID: 35663858 PMCID: PMC9159917 DOI: 10.3389/fmicb.2022.850807] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 03/31/2022] [Indexed: 11/13/2022] Open
Abstract
Malic acid is a component of the rhizosphere exudate and is vital for crop growth. However, little information is available about the effects of external applications of malic acid on the nutrient absorption and quality of grape fruit, and few studies have been performed on the relationship between the changes in the rhizosphere microbial community and nutrient absorption and fruit quality of grapes after adding malic acid. Here, the LM (low concentration of malic acid) and HM (high concentration of malic acid) treatments comprised 5% and 10% malic acid (the ratio of acid to the total weight of the fertilizer) combined with NPK fertilizer, respectively. Applying malic acid changed the grape rhizosphere microbial community structure and community-level physiological profile (CLPP) significantly, and HM had a positive effect on the utilization of substrates. The microbial community structure in the rhizosphere of the grapes with added malic acid was closely related to the CLPP. The N and P content in the leaves and fruits increased after applying malic acid compared to the control, while K content in the fruits increased significantly. In addition, malic acid significantly reduced the weight per fruit, significantly increased soluble sugar content (SSC) and vitamin C content of the fruit, and significantly improved the fruit sugar-acid ratio and grape tasting score. Moreover, the principal component analysis and grape nutrient and fruit quality scores showed that grape nutrients and fruit quality were significantly affected by malic acid and ranked as 5% malic acid > 10% malic acid > control. Pearson's correlation heatmap of microbial composition, nutrient absorption and fruit quality of the grapes showed that the grape microbial community was closely related to grape nutrients and fruit quality. Adding malic acid was positively correlated to Planococcaceae, Bacillaceae, Woeseiaceae and Rhodobacteraceae. Furthermore, Planococcaceae, Bacillaceae, Woeseiaceae and Rhodobacteraceae were closely related to grape nutrient absorption and fruit quality. Bacillaceae and Woeseiaceae were positively correlated with total soluble sugar, while Planococcaceae and Rhodobacteraceae were positively correlated with titratable acid. Hence, Bacillaceae and Woeseiaceae were the key bacteria that played a major role in grape fruit quality and nutrient absorption after applying malic acid water-soluble fertilizer.
Collapse
Affiliation(s)
- Peng Si
- College of Horticulture, Hebei Agricultural University, Baoding, China
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Zhengzhou, China
| | - Wei Shao
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Zhengzhou, China
- College of Forestry, Henan Agricultural University, Zhengzhou, China
| | - Huili Yu
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Zhengzhou, China
| | - Guoyi Xu
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Zhengzhou, China
| | - Guoqiang Du
- College of Horticulture, Hebei Agricultural University, Baoding, China
| |
Collapse
|
28
|
Ivo Ganchev. Role of Multispecies Biofilms with a Dominance of Bacillus subtilis in the Rhizosphere. BIOL BULL+ 2022. [DOI: 10.1134/s1062359021150061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
29
|
Zhang H, Qian Y, Fan D, Tian Y, Huang X. Biofilm formed by Hansschlegelia zhihuaiae S113 on root surface mitigates the toxicity of bensulfuron-methyl residues to maize. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 292:118366. [PMID: 34653590 DOI: 10.1016/j.envpol.2021.118366] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 09/20/2021] [Accepted: 10/11/2021] [Indexed: 06/13/2023]
Abstract
Bensulfuron-methyl (BSM) residues in soil threaten the rotation of BSM-sensitive crops. Microbial biofilms formed on crop roots could improve the ability of microbes to survive and protect crop roots. However, the research on biofilms with the purpose of mitigating or even eliminating BSM damage to sensitive crops is very limited. In this study, one BSM-degrading bacterium, Hansschlegelia zhihuaiae S113, colonized maize roots by forming a biofilm. Root exudates were associated with increased BSM degradation efficiency with strain S113 in rhizosphere soil relative to bulk soil, so the interactions among BSM degradation, root exudates, and biofilms may provide a new approach for the BSM-contaminated soil bioremediation. Root exudates and their constituent organic acids, including fumaric acid, tartaric acid, and l-malic acid, enhanced biofilm formation with 13.0-22.2% increases, owing to the regulation of genes encoding proteins responsible for cell motility/chemotaxis (fla/che cluster) and materials metabolism, thus promoting S113 population increases. Additionally, root exudates were also able to induce exopolysaccharide production to promote mature biofilm formation. Complete BSM degradation and healthy maize growth were found in BSM-contaminated rhizosphere soil treated with wild strain S113, compared to that treated with loss-of-function mutants ΔcheA-S113 (89.3%, without biofilm formation ability) and ΔsulE-S113 (22.1%, without degradation ability) or sterile water (10.7%, control). Furthermore, the biofilm mediated by organic acids, such as l-malic acid, exhibited a more favorable effect on BSM degradation and maize growth. These results showed that root exudates and their components (such as organic acids) can induce the biosynthesis of the biofilm to promote BSM degradation, emphasizing the contribution of root biofilm in reducing BSM damage to maize.
Collapse
Affiliation(s)
- Hao Zhang
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, PR China; College of Life Science and Agricultural Engineering, Nanyang Normal University, Nanyang, 473061, PR China; Innovation Center of Water Security for Water Source Region of Mid-route Project of South-North Water Diversion of Henan Province, Nanyang Normal University, Nanyang, 473061, PR China
| | - Yingying Qian
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Dandan Fan
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Yanning Tian
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Xing Huang
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, PR China.
| |
Collapse
|
30
|
He P, Li S, Xu S, Fan H, Wang Y, Zhou W, Fu G, Han G, Wang YY, Zheng SJ. Monitoring Tritrophic Biocontrol Interactions Between Bacillus spp., Fusarium oxysporum f. sp. cubense, Tropical Race 4, and Banana Plants in vivo Based on Fluorescent Transformation System. Front Microbiol 2021; 12:754918. [PMID: 34721361 PMCID: PMC8550332 DOI: 10.3389/fmicb.2021.754918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 09/22/2021] [Indexed: 11/27/2022] Open
Abstract
Bacillus spp. is effective biocontrol agents for Fusarium wilt of banana (FWB), tropical race 4 (TR4). This study explores the colonization by Bacillus subtilis, Bacillus velezensis, and Bacillus amyloliquefaciens of host banana plants and elucidates the mechanism of antagonistic TR4 biocontrol. The authors selected one B. subtilis strain, three B. velezensis strains, and three B. amyloliquefaciens strains that are proven to significantly inhibit TR4 in vitro, optimized the genetic transformation conditions and explored their colonization process in banana plants. The results showed that we successfully constructed an optimized fluorescent electro-transformation system (OD600 of bacteria concentration=0.7, plasmid concentration=50ng/μl, plasmid volume=2μl, transformation voltage=1.8kV, and transformation capacitance=400Ω) of TR4-inhibitory Bacillus spp. strains. The red fluorescent protein (RFP)-labeled strains were shown to have high stability with a plasmid-retention frequency above 98%, where bacterial growth rates and TR4 inhibition are unaffected by fluorescent plasmid insertion. In vivo colonizing observation by Laser Scanning Confocal Microscopy (LSCM) and Scanning Electron Microscopy (SEM) showed that Bacillus spp. can colonize the internal cells of banana plantlets roots. Further, fluorescent observation by LSCM showed these RFP-labeled bacteria exhibit chemotaxis (chemotaxis ratio was 1.85±0.04) toward green fluorescent protein (GFP)-labeled TR4 hyphae in banana plants. We conclude that B. subtilis, B. velezensis, and B. amyloliquefaciens can successfully colonize banana plants and interact with TR4. Monitoring its dynamic interaction with TR4 and its biocontrol mechanism is under further study.
Collapse
Affiliation(s)
- Ping He
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Ministry of Education Key Laboratory of Agriculture Biodiversity for Plant Disease Management, College of Plant Protection, Yunnan Agricultural University, Kunming, China.,Yunnan Key Laboratory of Green Prevention and Control of Agricultural Transboundary Pests, Agricultural Environment and Resources Institute, Yunnan Academy of Agricultural Sciences, Kunming, China
| | - Shu Li
- Yunnan Key Laboratory of Green Prevention and Control of Agricultural Transboundary Pests, Agricultural Environment and Resources Institute, Yunnan Academy of Agricultural Sciences, Kunming, China
| | - Shengtao Xu
- Yunnan Key Laboratory of Green Prevention and Control of Agricultural Transboundary Pests, Agricultural Environment and Resources Institute, Yunnan Academy of Agricultural Sciences, Kunming, China
| | - Huacai Fan
- Yunnan Key Laboratory of Green Prevention and Control of Agricultural Transboundary Pests, Agricultural Environment and Resources Institute, Yunnan Academy of Agricultural Sciences, Kunming, China
| | - Yongfen Wang
- Yunnan Key Laboratory of Green Prevention and Control of Agricultural Transboundary Pests, Agricultural Environment and Resources Institute, Yunnan Academy of Agricultural Sciences, Kunming, China.,Institute of Tropical and Subtropical Industry Crops, Yunnan Academy of Agricultural Sciences, Baoshan, China
| | - Wei Zhou
- Biotechnology Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, China
| | - Gang Fu
- Institute of Plant Protection, Guangxi Academy of Agricultural Sciences, Nanning, China
| | - Guangyu Han
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Ministry of Education Key Laboratory of Agriculture Biodiversity for Plant Disease Management, College of Plant Protection, Yunnan Agricultural University, Kunming, China
| | - Yun-Yue Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Ministry of Education Key Laboratory of Agriculture Biodiversity for Plant Disease Management, College of Plant Protection, Yunnan Agricultural University, Kunming, China
| | - Si-Jun Zheng
- Yunnan Key Laboratory of Green Prevention and Control of Agricultural Transboundary Pests, Agricultural Environment and Resources Institute, Yunnan Academy of Agricultural Sciences, Kunming, China.,Bioversity International, Kunming, China
| |
Collapse
|
31
|
Xue L, Sun B, Yang Y, Jin B, Zhuang G, Bai Z, Zhuang X. Efficiency and mechanism of reducing ammonia volatilization in alkaline farmland soil using Bacillus amyloliquefaciens biofertilizer. ENVIRONMENTAL RESEARCH 2021; 202:111672. [PMID: 34265351 DOI: 10.1016/j.envres.2021.111672] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 06/09/2021] [Accepted: 07/06/2021] [Indexed: 06/13/2023]
Abstract
Ammonia volatilization from the farmland caused by the application of synthetic nitrogen fertilizer is the most important source of anthropogenic ammonia emissions. Biofertilizer application has been considered as an alternative option for agriculture sustainability and soil improvement. In this study, field trials were carried out to investigate the efficiency of Bacillus amyloliquefaciens (BA) biofertilizer on alleviating ammonia volatilization in alkaline farmland soil and increasing crop yield and nitrogen utilization. Potential response mechanisms were investigated from soil enzyme, nitrogen cycle function genes and microbial community levels. Compared with conventional fertilization, BA biofertilizer application reduced the ammonia volatilization by 68%, increased the crop yield and nitrogen recovery by 19% and 19%, respectively. Soil enzyme activity analysis showed that BA biofertilizer inhibited the urease activity and enhanced the potential ammonia oxidation (PAO). In addition, BA biofertilizer application also increased the bacterial amoA gene abundance, while decreased the ureC gene abundance. BA biofertilizer also significantly altered the community structure and composition, and especially raised the abundance of ammonia oxidation bacteria (AOB), while no changes were observed in abundance of nitrite oxidation bacteria (NOB). Briefly, BA biofertilizer was approved to reduce the transformation of fertilizer nitrogen to NH4+-N, simultaneously accelerating NH4+-N into the nitrification process, thus decreasing the NH4+-N content remained in alkaline soil and consequently alleviating the ammonia volatilization. Thus, these results suggested that the application of BA biofertilizer is a feasible strategy to improve crop yields and reduce agricultural ammonia emissions.
Collapse
Affiliation(s)
- Lixia Xue
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; School of Civil Engineering, Lanzhou University of Technology, Lanzhou, 730050, China; Gansu Engineering Design Research Institute Co., Ltd. Lanzhou, 730030, China
| | - Bo Sun
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yahong Yang
- School of Civil Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Bo Jin
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA, 5005, Australia
| | - Guoqiang Zhuang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhihui Bai
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Xuliang Zhuang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
| |
Collapse
|
32
|
Wang JF, Li WL, Ahmad I, He BY, Wang LL, He T, Wang FP, Xu ZM, Li QS. Biomineralization of Cd 2+ and inhibition on rhizobacterial Cd mobilization function by Bacillus Cereus to improve safety of maize grains. CHEMOSPHERE 2021; 283:131095. [PMID: 34144288 DOI: 10.1016/j.chemosphere.2021.131095] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/28/2021] [Accepted: 06/01/2021] [Indexed: 06/12/2023]
Abstract
Reducing cadmium (Cd) bioavailability and rhizobacterial Cd mobilization functions in the rhizosphere via the inoculation of screened microbial inoculum is an environmental-friendly strategy to improve safety of crop grains. In this study, Bacillus Cereus, a model Cd resistant strain, was selected to explore its effects on Cd bioavailability and uptake, bacterial metabolic functions related to Cd mobilization. Results indicated that inoculation of Bacillus Cereus in maize roots of sand pot with water-soluble Cd (0.06-0.15 mg/kg) and soil pot with high Cd-contaminated soil (total Cd: 2.33 mg/kg; Cd extracted by NH4NO3: 38.6 μg/kg) could decrease water-soluble Cd ion concentration by 7.7-30.1% and Cd extracted with NH4NO3 solution by 7.8-22.5%, inducing Cd concentrations in maize grains reduced by 10.6-39.9% and 17.4-38.6%, respectively. Even for a single inoculation in soil, Cd concentration in maize grains still satisfy food safety requirements (Cd content: 0.1 mg/kg dry weight) due to its successful colonization on root surface of maize. Bacillus Cereus could enrich more plant growth promotion bacteria (PGPB) and down-regulate the expression of genes related to bacterial motility, membrane transports, carbon and nitrogen metabolism in the rhizosphere soil, decreasing Cd bioavailability in soil. Approximately 80% Cd2+ in media was transferred into intracellular, meanwhile Cd salts (sulfide and/or phosphate) were produced in Bacillus Cereus through biomineralization process. Overall, this study could provide a feasible method for improving safety of maize grains via the inoculation of Bacillus Cereus under Cd pollution.
Collapse
Affiliation(s)
- Jun-Feng Wang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 510632, China
| | - Wan-Li Li
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 510632, China
| | - Iftikhar Ahmad
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari Campus, Vehari, 61100, Pakistan
| | - Bao-Yan He
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 510632, China
| | - Li-Li Wang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 510632, China
| | - Tao He
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 510632, China
| | - Fo-Peng Wang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 510632, China
| | - Zhi-Min Xu
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 510632, China
| | - Qu-Sheng Li
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou, 510632, China.
| |
Collapse
|
33
|
Structural and functional characterization of the bacterial biofilm activator RemA. Nat Commun 2021; 12:5707. [PMID: 34588455 PMCID: PMC8481266 DOI: 10.1038/s41467-021-26005-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 09/07/2021] [Indexed: 11/23/2022] Open
Abstract
Bacillus subtilis can form structurally complex biofilms on solid or liquid surfaces, which requires expression of genes for matrix production. The transcription of these genes is activated by regulatory protein RemA, which binds to poorly conserved, repetitive DNA regions but lacks obvious DNA-binding motifs or domains. Here, we present the structure of the RemA homologue from Geobacillus thermodenitrificans, showing a unique octameric ring with the potential to form a 16-meric superstructure. These results, together with further biochemical and in vivo characterization of B. subtilis RemA, suggests that the protein can wrap DNA around its ring-like structure through a LytTR-related domain. Biofilm formation in Bacillus subtilis requires expression of matrix production genes, which are upregulated by transcriptional activator RemA. Here, the authors show that RemA forms octameric rings with the potential to form a 16-meric superstructure, suggesting that the protein can wrap DNA through a LytTR-related domain.
Collapse
|
34
|
Luo C, Liu J, Bilal M, Liu X, Wang X, Dong F, Liu Y, Zang S, Yin X, Yang X, Zhu T, Zhang S, Zhang W, Li B. Extracellular lipopeptide bacillomycin L regulates serial expression of genes for modulating multicellular behavior in Bacillus velezensis Bs916. Appl Microbiol Biotechnol 2021; 105:6853-6870. [PMID: 34477941 DOI: 10.1007/s00253-021-11524-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 06/30/2021] [Accepted: 08/05/2021] [Indexed: 11/29/2022]
Abstract
In wild strains of Bacillus, a handful of extracellular natural products act as signals that can regulate multicellular behavior, but relatively little is known about molecular mechanisms' detail. We proposed a previously unreported molecular mechanism for triggering multicellularity in B. velezensis Bs916 by an endogenous cyclic lipopeptide, bacillomycin L. The genome-wide effect on gene expression was caused by the disruption of bacillomycin L gene cluster, and 100 µg/mL bacillomycin L was revealed by quantitative transcriptomics. A total of 878 differentially expressed genes among Bs916, Δbl, and Δbl + 100BL were identified and grouped into 9 functional categories. The transcription levels of 40 candidate genes were further evaluated by RT-qPCR analysis. The expression of eight candidate genes regulated by bacillomycin L in a dose-dependent manner was revealed by LacZ fusion experiment. Although the addition of bacillomycin L could not completely restore the expression levels of the differentially regulated genes in △bl, our results strongly suggest that bacillomycin L acts as a tuning signal of swarming motility and complex biofilm formation by indirectly regulating the expression levels of some two-component systems (TCSs) connector genes, particularly including several Raps that potentially regulate the phosphorylation levels of three major regulators ComA, DegU, and Spo0A.Key points• Proposed model for bacillomycin L regulation in B. velezensis Bs916.• Bacillomycin L can act as an extracellular signal to regulate the phosphorylation levels of three major regulators, ComA, DegU, and Spo0A and control the multicellular processes of vegetative growth, competent, motility, matrix production, sporulation, and autolysis.
Collapse
Affiliation(s)
- Chuping Luo
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China. .,Institute of Veterinary Medicine, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China.
| | - Jiachen Liu
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China
| | - Muhammad Bilal
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China
| | - Xuehui Liu
- Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiaohua Wang
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China
| | - Fei Dong
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China
| | - Yuan Liu
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China.,Institute of Veterinary Medicine, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Shanshan Zang
- Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiulian Yin
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China
| | - Xueting Yang
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China
| | - Tao Zhu
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China
| | - Shuangyu Zhang
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China
| | - Weifeng Zhang
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China
| | - Bin Li
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huai'an, 223003, China. .,Institute of Veterinary Medicine, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China.
| |
Collapse
|
35
|
Arnaouteli S, Bamford NC, Stanley-Wall NR, Kovács ÁT. Bacillus subtilis biofilm formation and social interactions. Nat Rev Microbiol 2021; 19:600-614. [PMID: 33824496 DOI: 10.1038/s41579-021-00540-9] [Citation(s) in RCA: 155] [Impact Index Per Article: 51.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/02/2021] [Indexed: 02/03/2023]
Abstract
Biofilm formation is a process in which microbial cells aggregate to form collectives that are embedded in a self-produced extracellular matrix. Bacillus subtilis is a Gram-positive bacterium that is used to dissect the mechanisms controlling matrix production and the subsequent transition from a motile planktonic cell state to a sessile biofilm state. The collective nature of life in a biofilm allows emergent properties to manifest, and B. subtilis biofilms are linked with novel industrial uses as well as probiotic and biocontrol processes. In this Review, we outline the molecular details of the biofilm matrix and the regulatory pathways and external factors that control its production. We explore the beneficial outcomes associated with biofilms. Finally, we highlight major advances in our understanding of concepts of microbial evolution and community behaviour that have resulted from studies of the innate heterogeneity of biofilms.
Collapse
Affiliation(s)
- Sofia Arnaouteli
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, UK
| | - Natalie C Bamford
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, UK
| | - Nicola R Stanley-Wall
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, UK.
| | - Ákos T Kovács
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kongens Lyngby, Denmark.
| |
Collapse
|
36
|
Abstract
Bacteriophage predation is an important factor in bacterial community dynamics and evolution. Phage-bacterium interaction has mainly been studied in lab cultures, while dynamics in natural habitats, and especially in the plant root niche, are underexplored. To better understand this process, we characterized infection of the soil bacterium Bacillus subtilis NCBI 3610 by the lytic phage SPO1 during growth in LB medium and compared it to root colonization. Resistance in vitro was primarily through modification of the phage receptor. However, this type of resistance reduced the ability to colonize the root. From a line that survived phage infection while retaining the ability to colonize the root, we identified a new phage resistance mechanism involving potassium (K+) ion influx modulation and enhanced biofilm formation. Furthermore, we show that potassium serves as a stimulator of root colonization among diverse growth-promoting bacilli species, with implications for plant health.
Collapse
|
37
|
Huang M, Bulut A, Shrestha B, Matera C, Grundler FMW, Schleker ASS. Bacillus firmus I-1582 promotes plant growth and impairs infection and development of the cyst nematode Heterodera schachtii over two generations. Sci Rep 2021; 11:14114. [PMID: 34239009 PMCID: PMC8266893 DOI: 10.1038/s41598-021-93567-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 06/25/2021] [Indexed: 11/09/2022] Open
Abstract
Plant-parasitic nematodes wreak havoc on crops by root parasitism worldwide. An approach to combat nematode root parasitism is the application of antagonistic microbes like the rhizobacterium Bacillus firmus I-1582 which is promoted as biological control agent. Although B. firmus is a known nematode antagonist in general, the underlying mechanisms about its interaction with nematodes and plants have not yet been elucidated. Therefore, we explored the influence of B. firmus I-1582 as well as its extracellular and secreted molecules on plant–nematode interaction utilizing the plant–pathogen system Arabidopsis thaliana–Heterodera schachtii. We demonstrated that B. firmus I-1582 is attracted by A. thaliana root exudates, particularly by those of young plants. The bacterium colonized the root and showed a strictly pH-dependent development and plant growth promotion effect. Our results revealed that root colonization by B. firmus I-1582 significantly protected A. thaliana from infestation by the beet cyst nematode whereas dead bacterial cells or the culture supernatant were not effective. The bacterium also negatively affected nematode reproduction as well as pathogenicity and development of next generation nematodes. The obtained results highlight B. firmus I-1582 as a promising biocontrol agent that is well suited as an element of integrated control management strategies in sustainable agriculture.
Collapse
Affiliation(s)
- Mengmeng Huang
- INRES-Department of Molecular Phytomedicine, Rheinische Friedrich-Wilhelms-University of Bonn, 53115, Bonn, Germany
| | - Aylin Bulut
- INRES-Department of Molecular Phytomedicine, Rheinische Friedrich-Wilhelms-University of Bonn, 53115, Bonn, Germany
| | - Bidhya Shrestha
- INRES-Department of Molecular Phytomedicine, Rheinische Friedrich-Wilhelms-University of Bonn, 53115, Bonn, Germany
| | - Christiane Matera
- INRES-Department of Molecular Phytomedicine, Rheinische Friedrich-Wilhelms-University of Bonn, 53115, Bonn, Germany
| | - Florian M W Grundler
- INRES-Department of Molecular Phytomedicine, Rheinische Friedrich-Wilhelms-University of Bonn, 53115, Bonn, Germany
| | - A Sylvia S Schleker
- INRES-Department of Molecular Phytomedicine, Rheinische Friedrich-Wilhelms-University of Bonn, 53115, Bonn, Germany.
| |
Collapse
|
38
|
Antequera‐Gómez ML, Díaz‐Martínez L, Guadix JA, Sánchez‐Tévar AM, Sopeña‐Torres S, Hierrezuelo J, Doan HK, Leveau JH, de Vicente A, Romero D. Sporulation is dispensable for the vegetable-associated life cycle of the human pathogen Bacillus cereus. Microb Biotechnol 2021; 14:1550-1565. [PMID: 33955675 PMCID: PMC8313275 DOI: 10.1111/1751-7915.13816] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/18/2021] [Accepted: 04/03/2021] [Indexed: 11/28/2022] Open
Abstract
Bacillus cereus is a common food-borne pathogen that is responsible for important outbreaks of food poisoning in humans. Diseases caused by B. cereus usually exhibit two major symptoms, emetic or diarrheic, depending on the toxins produced. It is assumed that after the ingestion of contaminated vegetables or processed food, spores of enterotoxigenic B. cereus reach the intestine, where they germinate and produce the enterotoxins that are responsible for food poisoning. In our study, we observed that sporulation is required for the survival of B. cereus in leaves but is dispensable in ready-to-eat vegetables, such as endives. We demonstrate that vegetative cells of B. cereus that are originally impaired in sporulation but not biofilm formation are able to reach the intestine and cause severe disorders in a murine model. Furthermore, our findings emphasise that the number of food poisoning cases associated with B. cereus is underestimated and suggest the need to revise the detection protocols, which are based primarily on spores and toxins.
Collapse
Affiliation(s)
- María Luisa Antequera‐Gómez
- Departamento de MicrobiologíaInstituto de Hortofruticultura Subtropical y Mediterránea "La Mayora"Universidad de Málaga‐Consejo Superior de Investigaciones Científicas (IHSM‐UMA‐CSIC)Universidad de MálagaBulevar Louis Pasteur 31 (Campus Universitario de teatinos)Málaga29071Spain
| | - Luis Díaz‐Martínez
- Departamento de MicrobiologíaInstituto de Hortofruticultura Subtropical y Mediterránea "La Mayora"Universidad de Málaga‐Consejo Superior de Investigaciones Científicas (IHSM‐UMA‐CSIC)Universidad de MálagaBulevar Louis Pasteur 31 (Campus Universitario de teatinos)Málaga29071Spain
| | - Juan Antonio Guadix
- Departamento de Biología AnimalFacultad de CienciasUniversidad de Málaga ‐ IBIMACampus de Teatinos s/nMálaga29071Spain
- Centro Andaluz de Nanomedicina y Biotecnología (BIONAND)Junta de AndalucíaUniversidad de MálagaC/ Severo Ochoa 35Campanillas (Málaga)29590Spain
| | - Ana María Sánchez‐Tévar
- Departamento de Biología AnimalFacultad de CienciasUniversidad de Málaga ‐ IBIMACampus de Teatinos s/nMálaga29071Spain
- Centro Andaluz de Nanomedicina y Biotecnología (BIONAND)Junta de AndalucíaUniversidad de MálagaC/ Severo Ochoa 35Campanillas (Málaga)29590Spain
| | - Sara Sopeña‐Torres
- Departamento de MicrobiologíaInstituto de Hortofruticultura Subtropical y Mediterránea "La Mayora"Universidad de Málaga‐Consejo Superior de Investigaciones Científicas (IHSM‐UMA‐CSIC)Universidad de MálagaBulevar Louis Pasteur 31 (Campus Universitario de teatinos)Málaga29071Spain
| | - Jesús Hierrezuelo
- Departamento de MicrobiologíaInstituto de Hortofruticultura Subtropical y Mediterránea "La Mayora"Universidad de Málaga‐Consejo Superior de Investigaciones Científicas (IHSM‐UMA‐CSIC)Universidad de MálagaBulevar Louis Pasteur 31 (Campus Universitario de teatinos)Málaga29071Spain
| | - Hung K. Doan
- Department of Plant PathologyUniversity of CaliforniaDavisCAUSA
| | | | - Antonio de Vicente
- Departamento de MicrobiologíaInstituto de Hortofruticultura Subtropical y Mediterránea "La Mayora"Universidad de Málaga‐Consejo Superior de Investigaciones Científicas (IHSM‐UMA‐CSIC)Universidad de MálagaBulevar Louis Pasteur 31 (Campus Universitario de teatinos)Málaga29071Spain
| | - Diego Romero
- Departamento de MicrobiologíaInstituto de Hortofruticultura Subtropical y Mediterránea "La Mayora"Universidad de Málaga‐Consejo Superior de Investigaciones Científicas (IHSM‐UMA‐CSIC)Universidad de MálagaBulevar Louis Pasteur 31 (Campus Universitario de teatinos)Málaga29071Spain
| |
Collapse
|
39
|
Nordgaard M, Mortensen RMR, Kirk NK, Gallegos‐Monterrosa R, Kovács ÁT. Deletion of Rap-Phr systems in Bacillus subtilis influences in vitro biofilm formation and plant root colonization. Microbiologyopen 2021; 10:e1212. [PMID: 34180604 PMCID: PMC8236291 DOI: 10.1002/mbo3.1212] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 05/27/2021] [Accepted: 06/01/2021] [Indexed: 12/19/2022] Open
Abstract
Natural isolates of the soil-dwelling bacterium Bacillus subtilis form robust biofilms under laboratory conditions and colonize plant roots. B. subtilis biofilm gene expression displays phenotypic heterogeneity that is influenced by a family of Rap-Phr regulatory systems. Most Rap-Phr systems in B. subtilis have been studied independently, in different genetic backgrounds and under distinct conditions, hampering true comparison of the Rap-Phr systems' impact on bacterial cell differentiation. Here, we investigated each of the 12 Rap-Phr systems of B.subtilis NCIB 3610 for their effect on biofilm formation. By studying single ∆rap-phr mutants, we show that despite redundancy between the cell-cell communication systems, deletion of each of the 12 Rap-Phr systems influences matrix gene expression. These Rap-Phr systems therefore enable fine-tuning of the timing and level of matrix production in response to specific conditions. Furthermore, some of the ∆rap-phr mutants demonstrated altered biofilm formation in vitro and colonization of Arabidopsis thaliana roots, but not necessarily similarly in both processes, indicating that the pathways regulating matrix gene expression and other factors important for biofilm formation may be differently regulated under these distinct conditions.
Collapse
Affiliation(s)
- Mathilde Nordgaard
- Bacterial Interactions and Evolution GroupDTU BioengineeringTechnical University of DenmarkLyngbyDenmark
| | | | - Nikolaj Kaae Kirk
- Bacterial Interactions and Evolution GroupDTU BioengineeringTechnical University of DenmarkLyngbyDenmark
| | | | - Ákos T. Kovács
- Bacterial Interactions and Evolution GroupDTU BioengineeringTechnical University of DenmarkLyngbyDenmark
| |
Collapse
|
40
|
Sucrose triggers a novel signaling cascade promoting Bacillus subtilis rhizosphere colonization. ISME JOURNAL 2021; 15:2723-2737. [PMID: 33772107 PMCID: PMC8397739 DOI: 10.1038/s41396-021-00966-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 03/02/2021] [Accepted: 03/15/2021] [Indexed: 11/26/2022]
Abstract
Beneficial rhizobacteria promote plant growth and protect plants against phytopathogens. Effective colonization on plant roots is critical for the rhizobacteria to exert beneficial activities. How bacteria migrate swiftly in the soil of semisolid or solid nature remains unclear. Here we report that sucrose, a disaccharide ubiquitously deployed by photosynthetic plants for fixed carbon transport and storage, and abundantly secreted from plant roots, promotes solid surface motility (SSM) and root colonization by Bacillus subtilis through a previously uncharacterized mechanism. Sucrose induces robust SSM by triggering a signaling cascade, first through extracellular synthesis of polymeric levan, which in turn stimulates strong production of surfactin and hyper-flagellation of the cells. B. subtilis poorly colonizes the roots of Arabidopsis thaliana mutants deficient in root-exudation of sucrose, while exogenously added sucrose selectively shapes the rhizomicrobiome associated with the tomato plant roots, promoting specifically bacilli and pseudomonad. We propose that sucrose activates a signaling cascade to trigger SSM and promote rhizosphere colonization by B. subtilis. Our findings also suggest a practicable approach to boost prevalence of beneficial Bacillus species in plant protection.
Collapse
|
41
|
Sharipova MR, Mardanova AM, Rudakova NL, Pudova DS. Bistability and Formation of the Biofilm Matrix as Adaptive Mechanisms during the Stationary Phase of Bacillus subtilis. Microbiology (Reading) 2021. [DOI: 10.1134/s002626172006017x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
|
42
|
Hou Q, Kolodkin-Gal I. Harvesting the complex pathways of antibiotic production and resistance of soil bacilli for optimizing plant microbiome. FEMS Microbiol Ecol 2021; 96:5872479. [PMID: 32672816 DOI: 10.1093/femsec/fiaa142] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/13/2020] [Indexed: 01/04/2023] Open
Abstract
A sustainable future increasing depends on our capacity to utilize beneficial plant microbiomes to meet our growing needs. Plant microbiome symbiosis is a hallmark of the beneficial interactions between bacteria and their host. Specifically, colonization of plant roots by biocontrol agents and plant growth-promoting bacteria can play an important role in maintaining the optimal rhizosphere environment, supporting plant growth and promoting its fitness. Rhizosphere communities confer immunity against a wide range of foliar diseases by secreting antibiotics and activating plant defences. At the same time, the rhizosphere is a highly competitive niche, with multiple microbial species competing for space and resources, engaged in an arms race involving the production of a vast array of antibiotics and utilization of a variety of antibiotic resistance mechanisms. Therefore, elucidating the mechanisms that govern antibiotic production and resistance in the rhizosphere is of great significance for designing beneficial communities with enhanced biocontrol properties. In this review, we used Bacillus subtilis and B. amyloliquefaciens as models to investigate the genetics of antibiosis and the potential for its translation of into improved plant microbiome performance.
Collapse
Affiliation(s)
- Qihui Hou
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ilana Kolodkin-Gal
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| |
Collapse
|
43
|
Hou Q, Keren-Paz A, Korenblum E, Oved R, Malitsky S, Kolodkin-Gal I. Weaponizing volatiles to inhibit competitor biofilms from a distance. NPJ Biofilms Microbiomes 2021; 7:2. [PMID: 33402677 PMCID: PMC7785731 DOI: 10.1038/s41522-020-00174-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 11/19/2020] [Indexed: 01/29/2023] Open
Abstract
The soil bacterium Bacillus subtilis forms beneficial biofilms that induce plant defences and prevent the growth of pathogens. It is naturally found in the rhizosphere, where microorganisms coexist in an extremely competitive environment, and thus have evolved a diverse arsenal of defence mechanisms. In this work, we found that volatile compounds produced by B. subtilis biofilms inhibited the development of competing biofilm colonies, by reducing extracellular matrix gene expression, both within and across species. This effect was dose-dependent, with the structural defects becoming more pronounced as the number of volatile-producing colonies increased. This inhibition was mostly mediated by organic volatiles, and we identified the active molecules as 3-methyl-1-butanol and 1-butanol. Similar results were obtained with biofilms formed by phylogenetically distinct bacterium sharing the same niche, Escherichia coli, which produced the biofilm-inhibiting 3-methyl-1-butanol and 2-nonanon. The ability of established biofilms to inhibit the development and spreading of new biofilms from afar might be a general mechanism utilized by bacterial biofilms to protect an occupied niche from the invasion of competing bacteria.
Collapse
Affiliation(s)
- Qihui Hou
- grid.13992.300000 0004 0604 7563Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Alona Keren-Paz
- grid.13992.300000 0004 0604 7563Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Elisa Korenblum
- grid.13992.300000 0004 0604 7563Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Rela Oved
- grid.13992.300000 0004 0604 7563Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Sergey Malitsky
- grid.13992.300000 0004 0604 7563Metabolic Profiling Unit, Weizmann Institute of Science, Rehovot, Israel
| | - Ilana Kolodkin-Gal
- grid.13992.300000 0004 0604 7563Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|
44
|
Blake C, Christensen MN, Kovács ÁT. Molecular Aspects of Plant Growth Promotion and Protection by Bacillus subtilis. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2021; 34:15-25. [PMID: 32986513 DOI: 10.1094/mpmi-08-20-0225-cr] [Citation(s) in RCA: 92] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Bacillus subtilis is one of the most widely studied plant growth-promoting rhizobacteria. It is able to promote plant growth as well as control plant pathogens through diverse mechanisms, including the improvement of nutrient availability and alteration of phytohormone homeostasis as well as the production of antimicrobials and triggering induced systemic resistance, respectively. Even though its benefits for crop production have been recognized and studied extensively under laboratory conditions, the success of its application in fields varies immensely. It is widely accepted that agricultural application of B. subtilis often fails because the bacteria are not able to persist in the rhizosphere. Bacterial colonization of plant roots is a crucial step in the interaction between microbe and plant and seems, therefore, to be of great importance for its growth promotion and biocontrol effects. A successful root colonization depends thereby on both bacterial traits, motility and biofilm formation, as well as on a signal interplay with the plant. This review addresses current knowledge about plant-microbial interactions of the B. subtilis species, including the various mechanisms for supporting plant growth as well as the necessity for the establishment of the relationship.[Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Collapse
Affiliation(s)
- Christopher Blake
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kgs. Lyngby, Denmark
| | | | - Ákos T Kovács
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kgs. Lyngby, Denmark
| |
Collapse
|
45
|
Sharma M, Saleh D, Charron JB, Jabaji S. A Crosstalk Between Brachypodium Root Exudates, Organic Acids, and Bacillus velezensis B26, a Growth Promoting Bacterium. Front Microbiol 2020; 11:575578. [PMID: 33123106 PMCID: PMC7573104 DOI: 10.3389/fmicb.2020.575578] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 09/10/2020] [Indexed: 12/23/2022] Open
Abstract
Plant growth-promoting rhizobacteria (PGPR) are associated with plant roots and use organic compounds that are secreted from root exudates as food and energy source. Root exudates can chemoattract and help bacteria to colonize the surface of plant roots by inducing chemotactic responses of rhizospheric bacteria. In this study, we show that root colonization of Brachypodium distachyon by Bacillus velezensis strain B26 depends on several factors. These include root exudates, organic acids, and their biosynthetic genes, chemotaxis, biofilm formation and the induction of biofilm encoding genes. Analysis of root exudates by GC-MS identified five intermediates of the TCA cycle; malic, fumaric, citric, succinic, oxaloacetic acids, and were subsequently evaluated. The strongest chemotactic responses were induced by malic, succinic, citric, and fumaric acids. In comparison, the biofilm formation was induced by all organic acids with maximal induction by citric acid. Relative to the control, the individual organic acids, succinic and citric acids activated the epsD gene related to EPS biofilm, and also the genes encoding membrane protein (yqXM) and hydrophobin component (bslA) of the biofilm of strain B26. Whereas epsA and epsB genes were highly induced genes by succinic acid. Similarly, concentrated exudates released from inoculated roots after 48 h post-inoculation also induced all biofilm-associated genes. The addition of strain B26 to wild type and to icdh mutant line led to a slight induction but not biologically significant relative to their respective controls. Thus, B26 has no effect on the expression of the ICDH gene, both in the wild type and the mutant backgrounds. Our results indicate that root exudates and individual organic acids play an important role in selective recruitment and colonization of PGPR and inducing biofilm. The current study increases the understanding of molecular mechanisms behind biofilm induction by organic acids.
Collapse
Affiliation(s)
- Meha Sharma
- Department of Plant Science, Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, Canada
| | - Dina Saleh
- Department of Plant Science, Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, Canada
| | - Jean-Benoit Charron
- Department of Plant Science, Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, Canada
| | - Suha Jabaji
- Department of Plant Science, Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, Canada
| |
Collapse
|
46
|
Negative Interplay between Biofilm Formation and Competence in the Environmental Strains of Bacillus subtilis. mSystems 2020; 5:5/5/e00539-20. [PMID: 32873610 PMCID: PMC7470987 DOI: 10.1128/msystems.00539-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The soil bacterium Bacillus subtilis can form robust biofilms, which are important for its survival in the environment. B. subtilis also exhibits natural competence. By investigating competence development in B. subtilisin situ during biofilm formation, we reveal that robust biofilm formation often greatly reduces the frequency of competent cells within the biofilm. We then characterize a cross-pathway regulation that allows cells in these two developmental events to undergo mutually exclusive cell differentiation during biofilm formation. Finally, we discuss potential biological implications of limiting competence in a bacterial biofilm. Environmental strains of the soil bacterium Bacillus subtilis have valuable applications in agriculture, industry, and biotechnology; however, environmental strains are genetically less accessible. This reduced accessibility is in sharp contrast to laboratory strains, which are well known for their natural competence, and a limitation in their applications. In this study, we observed that robust biofilm formation by environmental strains of B. subtilis greatly reduced the frequency of competent cells in the biofilm. By using model strain 3610, we revealed a cross-pathway regulation that allows biofilm matrix producers and competence-developing cells to undergo mutually exclusive cell differentiation. We further demonstrated that the competence activator ComK represses the key biofilm regulatory gene sinI by directly binding to the sinI promoter, thus blocking competent cells from simultaneously becoming matrix producers. In parallel, the biofilm activator SlrR represses competence through three distinct mechanisms involving both genetic regulation and cell morphological changes. Finally, we discuss the potential implications of limiting competence in a bacterial biofilm. IMPORTANCE The soil bacterium Bacillus subtilis can form robust biofilms, which are important for its survival in the environment. B. subtilis also exhibits natural competence. By investigating competence development in B. subtilisin situ during biofilm formation, we reveal that robust biofilm formation often greatly reduces the frequency of competent cells within the biofilm. We then characterize a cross-pathway regulation that allows cells in these two developmental events to undergo mutually exclusive cell differentiation during biofilm formation. Finally, we discuss potential biological implications of limiting competence in a bacterial biofilm.
Collapse
|
47
|
Peng N, Cai P, Mortimer M, Wu Y, Gao C, Huang Q. The exopolysaccharide-eDNA interaction modulates 3D architecture of Bacillus subtilis biofilm. BMC Microbiol 2020; 20:115. [PMID: 32410574 PMCID: PMC7227074 DOI: 10.1186/s12866-020-01789-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 04/16/2020] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Bacterial biofilms are surface-adherent microbial communities in which individual cells are surrounded by a self-produced extracellular matrix of polysaccharides, extracellular DNA (eDNA) and proteins. Interactions among matrix components within biofilms are responsible for creating an adaptable structure during biofilm development. However, it is unclear how the interactions among matrix components contribute to the construction of the three-dimensional (3D) biofilm architecture. RESULTS DNase I treatment significantly inhibited Bacillus subtilis biofilm formation in the early phases of biofilm development. Confocal laser scanning microscopy (CLSM) and image analysis revealed that eDNA was cooperative with exopolysaccharide (EPS) in the early stages of B. subtilis biofilm development, while EPS played a major structural role in the later stages. In addition, deletion of the EPS production gene epsG in B. subtilis SBE1 resulted in loss of the interaction between EPS and eDNA and reduced the biofilm biomass in pellicles at the air-liquid interface. The physical interaction between these two essential biofilm matrix components was confirmed by isothermal titration calorimetry (ITC). CONCLUSIONS Biofilm 3D structures become interconnected through surrounding eDNA and EPS. eDNA interacts with EPS in the early phases of biofilm development, while EPS mainly participates in the maturation of biofilms. The findings of this study provide a better understanding of the role of the interaction between eDNA and EPS in shaping the biofilm 3D matrix structure and biofilm formation.
Collapse
Affiliation(s)
- Na Peng
- State Key Laboratory of Agricultural Microbiology, College of Resources of Environment, Huazhong Agricultural University, Wuhan, 430070 China
| | - Peng Cai
- State Key Laboratory of Agricultural Microbiology, College of Resources of Environment, Huazhong Agricultural University, Wuhan, 430070 China
| | - Monika Mortimer
- Bren School of Environmental Science and Management and Earth Research Institute, University of California, Santa Barbara, California, 93106 USA
| | - Yichao Wu
- State Key Laboratory of Agricultural Microbiology, College of Resources of Environment, Huazhong Agricultural University, Wuhan, 430070 China
| | - Chunhui Gao
- State Key Laboratory of Agricultural Microbiology, College of Resources of Environment, Huazhong Agricultural University, Wuhan, 430070 China
| | - Qiaoyun Huang
- State Key Laboratory of Agricultural Microbiology, College of Resources of Environment, Huazhong Agricultural University, Wuhan, 430070 China
| |
Collapse
|
48
|
Multiple and Overlapping Functions of Quorum Sensing Proteins for Cell Specialization in Bacillus Species. J Bacteriol 2020; 202:JB.00721-19. [PMID: 32071096 DOI: 10.1128/jb.00721-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In bacterial populations, quorum sensing (QS) systems participate in the regulation of specialization processes and regulate collective behaviors that mediate interactions and allow survival of the species. In Gram-positive bacteria, QS systems of the RRNPP family (Rgg, Rap, NprR, PlcR, and PrgX) consist of intracellular receptors and their cognate signaling peptides. Two of these receptors, Rap and NprR, have regained attention in Bacillus subtilis and the Bacillus cereus group. Some Rap proteins, such as RapH and Rap60, are multifunctional and/or redundant in function, linking the specialization processes of sporulation and competence, as well as global expression changes in the transition phase in B. subtilis NprR, an evolutionary intermediate between Rap and RRNPP transcriptional activators, is a bifunctional regulator that modulates sporulation initiation and activates nutrient scavenging genes. In this review, we discuss how these receptors switch between functions and connect distinct signaling pathways. Based on structural evidence, we propose that RapH and Rap60 should be considered moonlighting proteins. Additionally, we analyze an evolutionary and ecological perspective to understand the multifunctionality and functional redundancy of these regulators in both Bacillus spp. and non-Bacillus Firmicutes Understanding the mechanistic, structural, ecological, and evolutionary basis for the multifunctionality and redundancy of these QS systems is a key step for achieving the development of innovative technologies for health and agriculture.
Collapse
|
49
|
Sampedro I, Pérez-Mendoza D, Toral L, Palacios E, Arriagada C, Llamas I. Effects of Halophyte Root Exudates and Their Components on Chemotaxis, Biofilm Formation and Colonization of the Halophilic Bacterium Halomonas Anticariensis FP35 T. Microorganisms 2020; 8:E575. [PMID: 32316222 PMCID: PMC7232322 DOI: 10.3390/microorganisms8040575] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 04/13/2020] [Accepted: 04/14/2020] [Indexed: 12/25/2022] Open
Abstract
Increase in soil salinity poses an enormous problem for agriculture and highlights the need for sustainable crop production solutions. Plant growth-promoting bacteria can be used to boost the growth of halophytes in saline soils. Salicornia is considered to be a promising salt-accumulating halophyte for capturing large amounts of carbon from the atmosphere. In addition, colonization and chemotaxis could play an important role in Salicornia-microbe interactions. In this study, the role of chemotaxis in the colonization of the halophilic siredophore-producing bacteria, Halomonas anticariensis FP35T, on Salicornia hispanica plants was investigated. The chemotactic response of FP35T to Salicornia root exudates showed optimum dependence at a salt concentration of 5 % NaCl (w/v). Oleanolic acid, the predominant compound in the exudates detected by HPLC and identified by UPLC-HRMS Q-TOF, acts as a chemoattractant. In vitro experiments demonstrated the enhanced positive effects of wild-type H. anticariensis strain FP35T on root length, shoot length, germination and the vigour index of S. hispanica. Furthermore, these positive effects partially depend on an active chemotaxis system, as the chemotaxis mutant H. anticariensis FP35 ΔcheA showed reduced plant growth promotion for all the parameters tested. Overall, our results suggest that chemotaxis responses to root exudates play an important role in interactions between Salicornia and halophilic bacteria, enhance their colonization and boost plant growth promotion. Preliminary results also indicate that root exudates have a positive impact on H. anticariensis FP35T biofilm formation under saline conditions, an effect which totally depends on the presence of the cheA gene.
Collapse
Affiliation(s)
- Inmaculada Sampedro
- Department of Microbiology, Pharmacy Faculty, Campus de Cartuja s/n, 18071 Granada, Spain; (D.P.-M.); (E.P.); (I.L.)
- Biomedical Research Center (CIBM), Biotechnology Institute, Avda del Conocimiento s/n, 18100 Armilla, Granada, Spain
| | - Daniel Pérez-Mendoza
- Department of Microbiology, Pharmacy Faculty, Campus de Cartuja s/n, 18071 Granada, Spain; (D.P.-M.); (E.P.); (I.L.)
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, Spanish National Research Council (CSIC), Profesor Albareda 1, 18008 Granada, Spain
| | - Laura Toral
- Xtrem Biotech S.L., European Business Innovation Center, Avenida de la Innovación, 1, 18016 Armilla, Granada, Spain;
| | - Esther Palacios
- Department of Microbiology, Pharmacy Faculty, Campus de Cartuja s/n, 18071 Granada, Spain; (D.P.-M.); (E.P.); (I.L.)
- Biomedical Research Center (CIBM), Biotechnology Institute, Avda del Conocimiento s/n, 18100 Armilla, Granada, Spain
| | - César Arriagada
- Department of Forestry Science, Bioremediation Laboratory, Faculty of Agricultural and Forestry Science, University of La Frontera, 01145 Temuco, Chile;
| | - Inmaculada Llamas
- Department of Microbiology, Pharmacy Faculty, Campus de Cartuja s/n, 18071 Granada, Spain; (D.P.-M.); (E.P.); (I.L.)
- Biomedical Research Center (CIBM), Biotechnology Institute, Avda del Conocimiento s/n, 18100 Armilla, Granada, Spain
| |
Collapse
|
50
|
Tian T, Reverdy A, She Q, Sun B, Chai Y. The role of rhizodeposits in shaping rhizomicrobiome. ENVIRONMENTAL MICROBIOLOGY REPORTS 2020; 12:160-172. [PMID: 31858707 DOI: 10.1111/1758-2229.12816] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 12/09/2019] [Accepted: 12/10/2019] [Indexed: 05/22/2023]
Abstract
Rhizomicrobiome, the communities of microorganisms surrounding the root of the plant, plays a vital role in promoting plant growth and health. The composition of rhizomicrobiome is dynamic both temporally and spatially, and is influenced greatly by the plant host and environmental factors. One of the key influencing factors is rhizodeposits, composed of root-released tissue cells, exudates, lysates, volatile compounds, etc. Rhizodeposits are rich in carbon and nitrogen elements, and able to select and fuel the growth of rhizomicrobiome. In this minireview, we overview the generation, composition and dynamics of rhizodeposits, and discuss recent work describing the general and specific impacts of rhizodeposits on rhizomicrobiome. We focus further on root exudates, the most dynamic component of rhizodeposits, and review recent progresses about the influence of specific root exudates in promoting bacterial root colonization, inducing biofilm development, acting as plant defence and shaping the rhizomicrobiome.
Collapse
Affiliation(s)
- Tao Tian
- Tianjin Academy of Agricultural Sciences, Institute of Plant Protection, Tianjin, China
- Department of Biology, Northeastern University, Boston, MA, USA
| | - Alicyn Reverdy
- Department of Biology, Northeastern University, Boston, MA, USA
| | - Qianxuan She
- Department of Biology, Northeastern University, Boston, MA, USA
| | - Bingbing Sun
- Tianjin Academy of Agricultural Sciences, Institute of Plant Protection, Tianjin, China
| | - Yunrong Chai
- Department of Biology, Northeastern University, Boston, MA, USA
| |
Collapse
|