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Guerrero-Egido G, Pintado A, Bretscher KM, Arias-Giraldo LM, Paulson JN, Spaink HP, Claessen D, Ramos C, Cazorla FM, Medema MH, Raaijmakers JM, Carrión VJ. bacLIFE: a user-friendly computational workflow for genome analysis and prediction of lifestyle-associated genes in bacteria. Nat Commun 2024; 15:2072. [PMID: 38453959 PMCID: PMC10920822 DOI: 10.1038/s41467-024-46302-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 02/21/2024] [Indexed: 03/09/2024] Open
Abstract
Bacteria have an extensive adaptive ability to live in close association with eukaryotic hosts, exhibiting detrimental, neutral or beneficial effects on host growth and health. However, the genes involved in niche adaptation are mostly unknown and their functions poorly characterized. Here, we present bacLIFE ( https://github.com/Carrion-lab/bacLIFE ) a streamlined computational workflow for genome annotation, large-scale comparative genomics, and prediction of lifestyle-associated genes (LAGs). As a proof of concept, we analyzed 16,846 genomes from the Burkholderia/Paraburkholderia and Pseudomonas genera, which led to the identification of hundreds of genes potentially associated with a plant pathogenic lifestyle. Site-directed mutagenesis of 14 of these predicted LAGs of unknown function, followed by plant bioassays, showed that 6 predicted LAGs are indeed involved in the phytopathogenic lifestyle of Burkholderia plantarii and Pseudomonas syringae pv. phaseolicola. These 6 LAGs encompassed a glycosyltransferase, extracellular binding proteins, homoserine dehydrogenases and hypothetical proteins. Collectively, our results highlight bacLIFE as an effective computational tool for prediction of LAGs and the generation of hypotheses for a better understanding of bacteria-host interactions.
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Affiliation(s)
- Guillermo Guerrero-Egido
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands
- Departamento de Microbiología, Facultad de Ciencias, Campus Universitario de Teatinos s/n, Universidad de Málaga, 29010, Málaga, Spain
- Departamento de Protección de Cultivos, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", Campus Universitario de Teatinos, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), 29010, Málaga, Spain
| | - Adrian Pintado
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
- Departamento de Microbiología, Facultad de Ciencias, Campus Universitario de Teatinos s/n, Universidad de Málaga, 29010, Málaga, Spain
- Departamento de Protección de Cultivos, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", Campus Universitario de Teatinos, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), 29010, Málaga, Spain
| | - Kevin M Bretscher
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands
- Departamento de Microbiología, Facultad de Ciencias, Campus Universitario de Teatinos s/n, Universidad de Málaga, 29010, Málaga, Spain
- Departamento de Protección de Cultivos, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", Campus Universitario de Teatinos, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), 29010, Málaga, Spain
| | - Luisa-Maria Arias-Giraldo
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands
| | - Joseph N Paulson
- Department of Data Sciences, N-Power Medicine, Redwood City, CA, 94063, USA
| | - Herman P Spaink
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Dennis Claessen
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Cayo Ramos
- Departamento de Protección de Cultivos, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", Campus Universitario de Teatinos, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), 29010, Málaga, Spain
- Área de Genética, Facultad de Ciencias, Campus Universitario de Teatinos s/n, Universidad de Málaga, 29010, Málaga, Spain
| | - Francisco M Cazorla
- Departamento de Microbiología, Facultad de Ciencias, Campus Universitario de Teatinos s/n, Universidad de Málaga, 29010, Málaga, Spain
- Departamento de Protección de Cultivos, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", Campus Universitario de Teatinos, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), 29010, Málaga, Spain
| | - Marnix H Medema
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
- Bioinformatics Group, Wageningen University, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Jos M Raaijmakers
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands
| | - Víctor J Carrión
- Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands.
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands.
- Departamento de Microbiología, Facultad de Ciencias, Campus Universitario de Teatinos s/n, Universidad de Málaga, 29010, Málaga, Spain.
- Departamento de Protección de Cultivos, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", Campus Universitario de Teatinos, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), 29010, Málaga, Spain.
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Xiao WN, Nunn GM, Fufeng AB, Belu N, Brookman RK, Halim A, Krysmanski EC, Cameron RK. Exploring Pseudomonas syringae pv. tomato biofilm-like aggregate formation in susceptible and PTI-responding Arabidopsis thaliana. MOLECULAR PLANT PATHOLOGY 2024; 25:e13403. [PMID: 37988240 PMCID: PMC10799205 DOI: 10.1111/mpp.13403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 10/06/2023] [Indexed: 11/23/2023]
Abstract
Bacterial biofilm-like aggregates have been observed in plants, but their role in pathogenicity is underinvestigated. In the present study, we observed that extracellular DNA and polysaccharides colocalized with green fluorescent protein (GFP)-expressing Pseudomonas syringae pv. tomato (Pst) aggregates in Arabidopsis leaves, suggesting that Pst aggregates are biofilms. GFP-expressing Pst, Pst ΔalgU ΔmucAB (Pst algU mutant), and Pst ΔalgD ΔalgU ΔmucAB (Pst algU algD mutant) were examined to explore the roles of (1) alginate, a potential biofilm component; (2) Pst AlgU, thought to regulate alginate biosynthesis and some type III secretion system effector genes; and (3) intercellular salicylic acid (SA) accumulation during pathogen-associated molecular pattern-triggered immunity (PTI). Pst formed extensive aggregates in susceptible plants, whereas aggregate numbers and size were reduced in Pst algU and Pst algD algU mutants, and both multiplied poorly in planta, suggesting that aggregate formation contributes to Pst success in planta. However, in SA-deficient sid2-2 plants, Pst algD algU mutant multiplication and aggregate formation were partially restored, suggesting plant-produced SA contributes to suppression of Pst aggregate formation. Pst algD algU mutants formed fewer and smaller aggregates than Pst algU mutants, suggesting both AlgU and AlgD contribute to Pst aggregate formation. Col-0 plants accumulated low levels of SA in response to Pst and both mutants (Pst algU and Pst algD algU), suggesting the regulatory functions of AlgU are not involved in suppressing SA-mediated plant defence. Plant PTI was associated with highly reduced Pst aggregate formation and accumulation of intercellular SA in flg22-induced PTI-responding wild-type Col-0, but not in PTI-incompetent fls2, suggesting intercellular SA accumulation by Arabidopsis contributes to suppression of Pst biofilm-like aggregate formation during PTI.
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Affiliation(s)
- Wantao N. Xiao
- Department of BiologyMcMaster UniversityHamiltonOntarioCanada
| | - Garrett M. Nunn
- Department of BiologyMcMaster UniversityHamiltonOntarioCanada
| | | | - Natalie Belu
- Department of BiologyMcMaster UniversityHamiltonOntarioCanada
| | | | - Abdul Halim
- Department of BiologyMcMaster UniversityHamiltonOntarioCanada
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Zhang J, Yang Q, Yue W, Yang B, Zhou W, Chen L, Huang X, Zhang W, Dong J, Ling J. Seagrass Thalassia hemprichii and associated bacteria co-response to the synergistic stress of ocean warming and ocean acidification. ENVIRONMENTAL RESEARCH 2023; 236:116658. [PMID: 37454799 DOI: 10.1016/j.envres.2023.116658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 06/07/2023] [Accepted: 07/11/2023] [Indexed: 07/18/2023]
Abstract
Seagrass meadows play vital ecological roles in the marine ecosystem. Global climate change poses considerable threats to seagrass survival. However, it is unclear how seagrass and its associated bacteria will respond under future complex climate change scenarios. This study explored the effects of ocean warming (+2 °C) and ocean acidification (-0.4 units) on seagrass physiological indexes and bacterial communities (sediment and rhizosphere bacteria) of the seagrass Thalassia hemprichii during an experimental exposure of 30 days. Results demonstrated that the synergistic effect of ocean warming and ocean acidification differed from that of one single factor on seagrass and the associated bacterial community. The seagrass showed a weak resistance to ocean warming and ocean acidification, which manifested through the increase in the activity of typical oxidoreductase enzymes. Moreover, the synergistic effect of ocean warming and ocean acidification caused a significant decrease in seagrass's chlorophyll content. Although the bacterial community diversity exhibited higher resistance to ocean warming and ocean acidification, further bacterial functional analysis revealed the synergistic effect of ocean warming and ocean acidification led to significant increases in SOX-related genes abundance which potentially supported the seagrass in resisting climate stress by producing sulfates and oxidizing hydrogen sulfide. More stable bacterial communities were detected in the seagrass rhizosphere under combined ocean warming and ocean acidification. While for one single environmental stress, simpler networks were detected in the rhizosphere. In addition, the observed significant correlations between several modules of the bacterial community and the physiological indexes of the seagrass indicate the possible intimate interaction between seagrass and bacteria under ocean warming and ocean acidification. This study extends our understanding regarding the role of seagrass associated bacterial communities and sheds light on both the prediction and preservation of the seagrass meadow ecosystems in response to global climate change.
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Affiliation(s)
- Jian Zhang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Sanya, 572000, PR China; Guangdong Provincial Observation and Research Station for Coastal Upwelling Ecosystem, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Shantou, 515041, PR China; Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, PR China
| | - Qingsong Yang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Sanya, 572000, PR China; Guangdong Provincial Observation and Research Station for Coastal Upwelling Ecosystem, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Shantou, 515041, PR China; Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, PR China
| | - Weizhong Yue
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, PR China
| | - Bing Yang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Weiguo Zhou
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Sanya, 572000, PR China; Guangdong Provincial Observation and Research Station for Coastal Upwelling Ecosystem, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Shantou, 515041, PR China; Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, PR China
| | - Luxiang Chen
- College of Marine Sciences, South China Agricultural University, Guangzhou, Guangdong, 510642, PR China
| | - Xiaofang Huang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Sanya, 572000, PR China; Guangdong Provincial Observation and Research Station for Coastal Upwelling Ecosystem, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Shantou, 515041, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Wenqian Zhang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Sanya, 572000, PR China; Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, PR China
| | - Junde Dong
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Sanya, 572000, PR China; Guangdong Provincial Observation and Research Station for Coastal Upwelling Ecosystem, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Shantou, 515041, PR China; Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, PR China.
| | - Juan Ling
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Sanya, 572000, PR China; Guangdong Provincial Observation and Research Station for Coastal Upwelling Ecosystem, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Shantou, 515041, PR China; Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, PR China.
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Senthil Kumar R, Koner S, Tsai HC, Chen JS, Huang SW, Hsu BM. Deciphering endemic rhizosphere microbiome community's structure towards the host-derived heavy metals tolerance and plant growth promotion functions in serpentine geo-ecosystem. JOURNAL OF HAZARDOUS MATERIALS 2023; 452:131359. [PMID: 37031672 DOI: 10.1016/j.jhazmat.2023.131359] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 03/21/2023] [Accepted: 04/02/2023] [Indexed: 05/03/2023]
Abstract
Environmental microbes in rhizosphere soil and surrounding plants have the potential to alter ecosystem functions. We investigated the microbial communities inhabiting the rhizosphere soils of both serpentine and non-serpentine rhizosphere zones to evaluate their heavy metal tolerance and ability to promote plant growth, utilizing 16S rRNA metabarcoding. The Biolog-EcoPlate technique was employed to determine how abiotic stress factors affect carbon utilization capacity by rhizospheric microbial communities in the serpentine geo-ecosystem. The phyla Proteobacteria, Acidobacteria, Bacteroidetes, and Nitrospirae colonized in the roots of Miscanthus sp., Biden sp., and Oryza sp. showed noticeable differences in different rhizosphere zones. The PICRUSt2-based analysis identified chromium/iron resistance genes (ceuE, chrA) and arsenic resistance genes (arsR, acr3, arsC) abundant in all the studied rhizosphere soils. Notably, nickel resistance genes (nikA, nikD, nikE, and nikR) from Arthrobacter, Microbacterium, and Streptomyces strongly correlate with functions related to solubilization of nickel and an increase in siderophore and IAA production. The abundance of Arthrobacter, Clostridium, Geobacter, Dechloromonas, Pseudomonas, and Flavobacterium was positively correlated with chromium and nickel but negatively correlated with the calcium/magnesium ratio. Our results contribute to a better understanding of the functions of plant-tolerant PGPR interaction in the heavy metal-contaminated rhizosphere and eco-physiological responses from long-term biological weathering.
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Affiliation(s)
- Rajendran Senthil Kumar
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi County, Taiwan
| | - Suprokash Koner
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi County, Taiwan; Department of Biomedical Sciences, National Chung Cheng University, Chiayi, Taiwan
| | - Hsin-Chi Tsai
- Department of Psychiatry, School of Medicine, Tzu Chi University, Hualien, Taiwan; Department of Psychiatry, Tzu-Chi General Hospital, Hualien, Taiwan
| | - Jung-Sheng Chen
- Department of Medical Research, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan
| | - Shih-Wei Huang
- Institute of Environmental Toxin and Emerging Contaminant, Cheng Shiu University, Kaohsiung, Taiwan; Center for Environmental Toxin and Emerging Contaminant Research, Chen Shiu University, Kaohsiung, Taiwan
| | - Bing-Mu Hsu
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi County, Taiwan; Department of Medical Research, Dalin Tzu Chi Hospital, The Buddhist Tze Chi Medical Foundation, Chiayi, Taiwan.
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Blanco-Romero E, Durán D, Garrido-Sanz D, Redondo-Nieto M, Martín M, Rivilla R. Adaption of Pseudomonas ogarae F113 to the Rhizosphere Environment-The AmrZ-FleQ Hub. Microorganisms 2023; 11:microorganisms11041037. [PMID: 37110460 PMCID: PMC10146422 DOI: 10.3390/microorganisms11041037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/10/2023] [Accepted: 04/13/2023] [Indexed: 04/29/2023] Open
Abstract
Motility and biofilm formation are two crucial traits in the process of rhizosphere colonization by pseudomonads. The regulation of both traits requires a complex signaling network that is coordinated by the AmrZ-FleQ hub. In this review, we describe the role of this hub in the adaption to the rhizosphere. The study of the direct regulon of AmrZ and the phenotypic analyses of an amrZ mutant in Pseudomonas ogarae F113 has shown that this protein plays a crucial role in the regulation of several cellular functions, including motility, biofilm formation, iron homeostasis, and bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) turnover, controlling the synthesis of extracellular matrix components. On the other hand, FleQ is the master regulator of flagellar synthesis in P. ogarae F113 and other pseudomonads, but its implication in the regulation of multiple traits related with environmental adaption has been shown. Genomic scale studies (ChIP-Seq and RNA-Seq) have shown that in P. ogarae F113, AmrZ and FleQ are general transcription factors that regulate multiple traits. It has also been shown that there is a common regulon shared by the two transcription factors. Moreover, these studies have shown that AmrZ and FleQ form a regulatory hub that inversely regulate traits such as motility, extracellular matrix component production, and iron homeostasis. The messenger molecule c-di-GMP plays an essential role in this hub since its production is regulated by AmrZ and it is sensed by FleQ and required for its regulatory role. This regulatory hub is functional both in culture and in the rhizosphere, indicating that the AmrZ-FleQ hub is a main player of P. ogarae F113 adaption to the rhizosphere environment.
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Affiliation(s)
- Esther Blanco-Romero
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| | - David Durán
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| | - Daniel Garrido-Sanz
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
- Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland
| | - Miguel Redondo-Nieto
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| | - Marta Martín
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| | - Rafael Rivilla
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
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Wu Y, Xiao S, Qi J, Gong Y, Li K. Pseudomonas fluorescens BsEB-1: an endophytic bacterium isolated from the root of Bletilla striata that can promote its growth. PLANT SIGNALING & BEHAVIOR 2022; 17:2100626. [PMID: 35922084 PMCID: PMC9354766 DOI: 10.1080/15592324.2022.2100626] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 07/06/2022] [Accepted: 07/06/2022] [Indexed: 06/15/2023]
Abstract
An endophytic Pseudomonas fluorescens (BsEB-1) was obtained from the roots of Bletilla striata. We investigated its growth-promoting properties and observed the impact of its inoculation on both the growth and polysaccharide content of Bletilla striata tubers. It was found that BsEB-1 possessed three growth-promoting activities: phosphate-solubilizing, produced indoleacetic acid (IAA) and siderophores, but had no nitrogen-fixing activity. BsEB-1 could rapidly attach to the root hairs of Bletilla striata tissue culture seedlings and endophytically colonize the region of maturation in the roots. It also significantly promoted the rooting and transplant survival rate of the seedlings, as well as the growth and expansion of the tubers, but did not increase their polysaccharide content. Pseudomonas fluorescens BsEB-1 exhibits potential for applications in the artificial planting of Bletilla striata.
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Affiliation(s)
- Yuanshuang Wu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, PR China
| | - Suhui Xiao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, PR China
| | - Jiaseng Qi
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, PR China
| | - Yongchang Gong
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, PR China
| | - Kunzhi Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, PR China
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Endophytic Pseudomonas sp. from Agave palmeri Participate in the Rhizophagy Cycle and Act as Biostimulants in Crop Plants. BIOLOGY 2022; 11:biology11121790. [PMID: 36552299 PMCID: PMC9775861 DOI: 10.3390/biology11121790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/03/2022] [Accepted: 12/07/2022] [Indexed: 12/13/2022]
Abstract
Plant growth-promoting bacteria are generating increasing interest in the agricultural industry as a promising alternative to traditional chemical fertilizers; however, much of the focus has been on rhizosphere bacteria. Bacterial endophytes are another promising source of plant growth-promoting bacteria, and though many plants have already been prospected for beneficial microbes, desert plants have been underrepresented in such studies. In this study, we show the growth-promoting potential of five strains of endophytic Pseudomonas sp. isolated from Agave palmeri, an agave from the Sonoran Desert. When inoculated onto Kentucky bluegrass, clover, carrot, coriander, and wheat, endophytic Pseudomonas sp. increased seedling root lengths in all hosts and seedling shoot lengths in Kentucky bluegrass, carrot, and wheat. Transformation of the Pseudomonas sp. strain P3AW to express the fluorescent protein mCherry revealed that Pseudomonas sp. becomes endophytic in non-native hosts and participates in parts of the rhizophagy cycle, a process by which endophytic bacteria cycle between the soil and roots, bringing in nutrients from the soil which are then extracted through reactive oxygen-mediated bacterial degradation in the roots. Tracking of the Pseudomonas sp. strain P3AW also provided evidence for a system of endophyte, or endophyte cell content, transport via the vascular bundle. These results provide further evidence of the rhizophagy cycle in plants and how it relates to growth promotion in plants by biostimulant bacteria.
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De Palma M, Scotti R, D’Agostino N, Zaccardelli M, Tucci M. Phyto-Friendly Soil Bacteria and Fungi Provide Beneficial Outcomes in the Host Plant by Differently Modulating Its Responses through (In)Direct Mechanisms. PLANTS (BASEL, SWITZERLAND) 2022; 11:2672. [PMID: 36297696 PMCID: PMC9612229 DOI: 10.3390/plants11202672] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/08/2022] [Accepted: 10/09/2022] [Indexed: 06/16/2023]
Abstract
Sustainable agricultural systems based on the application of phyto-friendly bacteria and fungi are increasingly needed to preserve soil fertility and microbial biodiversity, as well as to reduce the use of chemical fertilizers and pesticides. Although there is considerable attention on the potential applications of microbial consortia as biofertilizers and biocontrol agents for crop management, knowledge on the molecular responses modulated in host plants because of these beneficial associations is still incomplete. This review provides an up-to-date overview of the different mechanisms of action triggered by plant-growth-promoting microorganisms (PGPMs) to promote host-plant growth and improve its defense system. In addition, we combined available gene-expression profiling data from tomato roots sampled in the early stages of interaction with Pseudomonas or Trichoderma strains to develop an integrated model that describes the common processes activated by both PGPMs and highlights the host's different responses to the two microorganisms. All the information gathered will help define new strategies for the selection of crop varieties with a better ability to benefit from the elicitation of microbial inoculants.
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Affiliation(s)
- Monica De Palma
- Institute of Biosciences and BioResources, Research Division Portici, National Research Council, 80055 Portici, Italy
| | - Riccardo Scotti
- CREA Research Centre for Vegetable and Ornamental Crops, Via Cavalleggeri 25, 84098 Pontecagnano Faiano (SA), Italy
| | - Nunzio D’Agostino
- Department of Agricultural Sciences, University of Naples Federico II, 80055 Portici, Italy
| | - Massimo Zaccardelli
- CREA Research Centre for Vegetable and Ornamental Crops, Via Cavalleggeri 25, 84098 Pontecagnano Faiano (SA), Italy
| | - Marina Tucci
- Institute of Biosciences and BioResources, Research Division Portici, National Research Council, 80055 Portici, Italy
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9
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Lescallette AR, Dunn ZD, Manning VA, Trippe KM, Li B. Biosynthetic Origin of Formylaminooxyvinylglycine and Characterization of the Formyltransferase GvgI. Biochemistry 2022; 61:2159-2164. [PMID: 36126313 DOI: 10.1021/acs.biochem.2c00374] [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] [Indexed: 11/29/2022]
Abstract
4-Formylaminooxyvinylglycine (FVG) is an herbicidal and antibacterial nonproteinogenic amino acid produced by several strains of the Pseudomonas fluorescens species complex. It contains a unique vinyl alkoxyamine moiety with an O-N bond, and its biosynthetic origin remains unknown. Here, we show that the gvg cluster from P. fluorescens WH6 is responsible for the biosynthesis of FVG and two additional O-N bond-containing oxyvinylglycines, guanidinooxyvinylglycine and aminooxyvinylglycine. Feeding studies in the producing bacteria indicate that these compounds originate from homoserine. We identify a formyltransferase gvgI that is required for the production of FVG and characterize the activity of this enzyme in vitro toward amino acids with a side chain amine. Sequence similarity network analysis reveals that GvgI and homologues make up a distinct group from the main classes of formyltransferases.
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Affiliation(s)
- Adam R Lescallette
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Zachary D Dunn
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Viola A Manning
- USDA-ARS Forage Seed and Cereal Research Unit, Corvallis, Oregon 97331, United States
- Department of Crop and Soil Science, Oregon State University, Corvallis, Oregon 97331, United States
| | - Kristin M Trippe
- USDA-ARS Forage Seed and Cereal Research Unit, Corvallis, Oregon 97331, United States
- Department of Crop and Soil Science, Oregon State University, Corvallis, Oregon 97331, United States
| | - Bo Li
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Department of Microbiology and Immunology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
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10
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Tran T, French E, Iyer-Pascuzzi AS. In vitro functional characterization predicts the impact of bacterial root endophytes on plant growth. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:5758-5772. [PMID: 35596672 DOI: 10.1093/jxb/erac228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
Utilizing beneficial microbes for crop improvement is one strategy to achieve sustainable agriculture. However, identifying microbial isolates that promote crop growth is challenging, in part because using bacterial taxonomy to predict an isolate's effect on plant growth may not be reliable. The overall aim of this work was to determine whether in vitro functional traits of bacteria were predictive of their in planta impact. We isolated 183 bacterial endophytes from field-grown roots of two tomato species, Solanum lycopersicum and S. pimpinellifolium. Sixty isolates were screened for six in vitro functional traits: auxin production, siderophore production, phosphate solubilization, antagonism to a soilborne pathogen, and the presence of two antimicrobial metabolite synthesis genes. Hierarchical clustering of the isolates based on the in vitro functional traits identified several groups of isolates sharing similar traits. We called these groups 'functional groups'. To understand how in vitro functional traits of bacteria relate to their impact on plants, we inoculated three isolates from each of the functional groups on tomato seedlings. Isolates within the same functional group promoted plant growth at similar levels, regardless of their host origin or taxonomy. Together, our results demonstrate the importance of examining root endophyte functions for improving crop production.
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Affiliation(s)
- Tri Tran
- Department of Botany and Plant Pathology, Center for Plant Biology, Purdue University, West Lafayette, IN, USA
| | - Elizabeth French
- Department of Botany and Plant Pathology, Center for Plant Biology, Purdue University, West Lafayette, IN, USA
| | - Anjali S Iyer-Pascuzzi
- Department of Botany and Plant Pathology, Center for Plant Biology, Purdue University, West Lafayette, IN, USA
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11
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Mhuireach GÁ, Dietz L, Gillett T. One or many? Multi-species livestock grazing influences soil microbiome community structure and antibiotic resistance potential. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2022. [DOI: 10.3389/fsufs.2022.926824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Soil health has been highlighted as a key dimension of regenerative agriculture, given its critical importance for food production, carbon sequestration, water filtration, and nutrient cycling. Microorganisms are critical components of soil health, as they are responsible for mediating 90% of soil functions. Multi-species rotational grazing (MSRG) is a promising strategy for maintaining and improving soil health, yet the potential effects of MSRG on soil microbiomes are poorly understood. To address this knowledge gap, we collected soil microbial samples at three timepoints during the 2020 grazing season for 12 total paddocks, which were equally split into four different grazing treatments—cattle only, sheep only, swine only, or multi-species. Shallow shotgun metagenomic sequencing was used to characterize soil microbial community taxonomy and antibiotic resistome. Results demonstrated broad microbial diversity in all paddock soil microbiomes. Samples collected early in the season tended to have greater archaeal and bacterial alpha diversity than samples collected later for all grazing treatments, while no effect was observed for fungi or viruses. Beta diversity, however, was strongly influenced by both grazing treatment and month for all microbial kingdoms, suggesting a pronounced effect of different livestock on microbial composition. Cattle-only and swine-only paddocks were more dissimilar from multi-species paddocks than those grazed by sheep. We identified a large number of differentially abundant taxa driving community dissimilarities, including Methanosarcina spp., Candidatus Nitrocosmicus oleophilus, Streptomyces spp., Pyricularia spp., Fusarium spp., and Tunggulvirus Pseudomonas virus ϕ-2. In addition, a wide variety of antibiotic resistance genes (ARGs) were present in all samples, regardless of grazing treatment; the majority of these encoded efflux pumps and antibiotic modification enzymes (e.g., transferases). This novel study demonstrates that grazing different species of livestock, either separately or together, can impact soil microbial community structure and antibiotic resistance capacity, though further research is needed to fully characterize these impacts. Increasing the knowledge base about soil microbial community structure and function under real-world grazing conditions will help to construct metrics that can be incorporated into traditional soil health tests and allow producers to manage livestock operations for optimal soil microbiomes.
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12
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Chi X, Wang Y, Miao J, Wang W, Sun Y, Yu Z, Feng Z, Cheng S, Chen L, Ge Y. EppR, a new LysR-family transcription regulator, positively influences phenazine biosynthesis in the plant growth-promoting rhizobacterium Pseudomonas chlororaphis G05. Microbiol Res 2022; 260:127050. [DOI: 10.1016/j.micres.2022.127050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 04/13/2022] [Accepted: 04/19/2022] [Indexed: 10/18/2022]
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13
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Panstruga R, Donnelly SC, Bernhagen J. A Cross-Kingdom View on the Immunomodulatory Role of MIF/D-DT Proteins in Mammalian and Plant Pseudomonas Infections. Immunology 2022; 166:287-298. [PMID: 35416298 DOI: 10.1111/imm.13480] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 01/04/2022] [Accepted: 03/09/2022] [Indexed: 11/26/2022] Open
Abstract
Gram-negative Pseudomonas bacteria are largely harmless saprotrophs, but some species can be potent pathogens of both plants and mammals. Macrophage migration inhibitory factor (MIF) and its homolog D-dopachrome tautomerase (D-DT, also referred to as MIF-2) are multifunctional proteins that in addition to their intracellular functions also serve as extracellular signaling molecules (cytokines) in orchestrating mammalian immune responses. It recently emerged that plants also possess MIF-like proteins, termed MIF/D-DT-like (MDL) proteins. We here provide a comparative cross-kingdom view on the immunomodulatory role of MIF and MDL proteins during Pseudomonas infections in mammals and plants. Although in both kingdoms the lack of MIF/MDL proteins is associated with a reduction in bacterial load and disease symptoms, the underlying molecular principles seem to be different. We provide a perspective for future research activities to unravel additional commonalities and differences in the MIF/MDL-mediated adjustment of antibacterial immune activities.
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Affiliation(s)
- Ralph Panstruga
- RWTH Aachen University, Institute for Biology I, Unit of Plant Molecular Cell Biology, Aachen, Germany
| | - Seamas C Donnelly
- Department of Medicine, Tallaght University Hospital & Trinity College Dublin, Dublin, Ireland
| | - Jürgen Bernhagen
- Chair of Vascular Biology, Institute for Stroke and Dementia Research (ISD), Ludwig-Maximilian-University (LMU) Munich, Munich, Germany
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14
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Díaz-Cruz GA, Cassone BJ. Changes in the phyllosphere and rhizosphere microbial communities of soybean in the presence of pathogens. FEMS Microbiol Ecol 2022; 98:fiac022. [PMID: 35195242 DOI: 10.1093/femsec/fiac022] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/20/2022] [Accepted: 02/21/2022] [Indexed: 11/13/2022] Open
Abstract
Soybean (Glycine max L.) is host to an array of foliar- and root-infecting pathogens that can cause significant yield losses. To provide insights into the roles of microorganisms in disease development, we evaluated the bacterial and fungal communities associated with the soybean rhizosphere and phyllosphere. For this, leaf and soil samples of healthy, Phytophthora sojae-infected and Septoria glycines-infected plants were sampled at three stages during the production cycle, and then subjected to 16S and Internal Transcribed Spacer (ITS) amplicon sequencing. The results indicated that biotic stresses did not have a significant impact on species richness and evenness regardless of growth stage. However, the structure and composition of soybean microbial communities were dramatically altered by biotic stresses, particularly for the fungal phyllosphere. Additionally, we cataloged a variety of microbial genera that were altered by biotic stresses and their associations with other genera, which could serve as biological indicators for disease development. In terms of soybean development, the rhizosphere and phyllosphere had distinct microbial communities, with the fungal phyllosphere most influenced by growth stage. Overall, this study characterized the phyllosphere and rhizosphere microbial communities of soybean, and described the impact of pathogen infection and plant development in shaping these bacterial and fungal communities.
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Affiliation(s)
- Gustavo A Díaz-Cruz
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada
- Department of Biology, Brandon University, Brandon, MB, R7A 6A9, Canada
| | - Bryan J Cassone
- Department of Biology, Brandon University, Brandon, MB, R7A 6A9, Canada
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15
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Yang R, Li S, Li Y, Yan Y, Fang Y, Zou L, Chen G. Bactericidal Effect of Pseudomonas oryziphila sp. nov., a Novel Pseudomonas Species Against Xanthomonas oryzae Reduces Disease Severity of Bacterial Leaf Streak of Rice. Front Microbiol 2021; 12:759536. [PMID: 34803984 PMCID: PMC8600968 DOI: 10.3389/fmicb.2021.759536] [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: 08/16/2021] [Accepted: 10/04/2021] [Indexed: 11/13/2022] Open
Abstract
Pseudomonas is a diverse genus of Gammaproteobacteria with increasing novel species exhibiting versatile trains including antimicrobial and insecticidal activity, as well as plant growth-promoting, which make them well suited as biocontrol agents of some pathogens. Here we isolated strain 1257 that exhibited strong antagonistic activity against two pathovars of Xanthomonas oryzae, especially X. oryzae pv. oryzicola (Xoc) responsible for the bacterial leaf streak (BLS) in rice. The phylogenetic, genomic, physiological, and biochemical characteristics support that strain 1257 is a representative of a novel Pseudomonas species that is most closely related to the entomopathogenic bacterium Pseudomonas entomophila. We propose to name it Pseudomonas oryziphila sp. nov. Comparative genomics analyses showed that P. oryziphila 1257 possesses most of the central metabolic genes of two closely related strains P. entomophila L48 and Pseudomonas mosselii CFML 90-83, as well as a set of genes encoding the type IV pilus system, suggesting its versatile metabolism and motility properties. Some features, such as insecticidal toxins, phosphate solubilization, indole-3-acetic acid, and phenylacetic acid degradation, were disclosed. Genome-wide random mutagenesis revealed that the non-ribosomal peptide catalyzed by LgrD may be a major active compound of P. oryziphila 1257 against Xoc RS105, as well as the critical role of the carbamoyl phosphate and the pentose phosphate pathway that control the biosynthesis of this target compound. Our findings demonstrate that 1257 could effectively inhibit the growth and migration of Xoc in rice tissue to prevent the BLS disease. To our knowledge, this is the first report of a novel Pseudomonas species that displays a strong antibacterial activity against Xoc. The results suggest that the P. oryziphila strain could be a promising biological control agent for BLS.
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Affiliation(s)
- Ruihuan Yang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Shengzhang Li
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Yilang Li
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Yichao Yan
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Yuan Fang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Lifang Zou
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.,State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, China
| | - Gongyou Chen
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.,State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, China
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16
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Vick SHW, Fabian BK, Dawson CJ, Foster C, Asher A, Hassan KA, Midgley DJ, Paulsen IT, Tetu SG. Delving into defence: identifying the Pseudomonas protegens Pf-5 gene suite involved in defence against secreted products of fungal, oomycete and bacterial rhizosphere competitors. Microb Genom 2021; 7. [PMID: 34788213 PMCID: PMC8743541 DOI: 10.1099/mgen.0.000671] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Competitive behaviours of plant growth promoting rhizobacteria (PGPR) are integral to their ability to colonize and persist on plant roots and outcompete phytopathogenic fungi, oomycetes and bacteria. PGPR engage in a range of antagonistic behaviours that have been studied in detail, such as the production and secretion of compounds inhibitory to other microbes. In contrast, their defensive activities that enable them to tolerate exposure to inhibitory compounds produced by their neighbours are less well understood. In this study, the genes involved in the Pseudomonas protegens Pf-5 response to metabolites from eight diverse rhizosphere competitor organisms, Fusarium oxysporum, Rhizoctonia solani, Gaeumannomyces graminis var. tritici, Pythium spinosum, Bacillus subtilis QST713, Pseudomonas sp. Q2-87, Streptomyces griseus and Streptomyces bikiniensis subspecies bikiniensi, were examined. Proximity induced excreted metabolite responses were confirmed for Pf-5 with all partner organisms through HPLC before culturing a dense Pf-5 transposon mutant library adjacent to each of these microbes. This was followed by transposon-directed insertion site sequencing (TraDIS), which identified genes that influence Pf-5 fitness during these competitive interactions. A set of 148 genes was identified that were associated with increased fitness during competition, including cell surface modification, electron transport, nucleotide metabolism, as well as regulatory genes. In addition, 51 genes were identified for which loss of function resulted in fitness gains during competition. These included genes involved in flagella biosynthesis and cell division. Considerable overlap was observed in the set of genes observed to provide a fitness benefit during competition with all eight test organisms, indicating commonalities in the competitive response to phylogenetically diverse micro-organisms and providing new insight into competitive processes likely to take place in the rhizosphere.
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Affiliation(s)
- Silas H W Vick
- Department of Molecular Sciences, Macquarie University, North Ryde, Australia.,Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, Australia.,Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway
| | - Belinda K Fabian
- Department of Molecular Sciences, Macquarie University, North Ryde, Australia.,ARC Centre of Excellence in Synthetic Biology, Macquarie University, North Ryde, Australia
| | - Catherine J Dawson
- School of Environmental and Life Sciences, University of Newcastle, Newcastle, Australia
| | - Christie Foster
- Department of Molecular Sciences, Macquarie University, North Ryde, Australia
| | - Amy Asher
- Department of Molecular Sciences, Macquarie University, North Ryde, Australia
| | - Karl A Hassan
- School of Environmental and Life Sciences, University of Newcastle, Newcastle, Australia
| | - David J Midgley
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, Australia
| | - Ian T Paulsen
- Department of Molecular Sciences, Macquarie University, North Ryde, Australia.,ARC Centre of Excellence in Synthetic Biology, Macquarie University, North Ryde, Australia
| | - Sasha G Tetu
- Department of Molecular Sciences, Macquarie University, North Ryde, Australia.,ARC Centre of Excellence in Synthetic Biology, Macquarie University, North Ryde, Australia
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17
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Abidi W, Torres-Sánchez L, Siroy A, Krasteva PV. Weaving of bacterial cellulose by the Bcs secretion systems. FEMS Microbiol Rev 2021; 46:6388354. [PMID: 34634120 PMCID: PMC8892547 DOI: 10.1093/femsre/fuab051] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 10/08/2021] [Indexed: 12/13/2022] Open
Abstract
Cellulose is the most abundant biological compound on Earth and while it is the predominant building constituent of plants, it is also a key extracellular matrix component in many diverse bacterial species. While bacterial cellulose was first described in the 19th century, it was not until this last decade that a string of structural works provided insights into how the cellulose synthase BcsA, assisted by its inner-membrane partner BcsB, senses c-di-GMP to simultaneously polymerize its substrate and extrude the nascent polysaccharide across the inner bacterial membrane. It is now established that bacterial cellulose can be produced by several distinct types of cellulose secretion systems and that in addition to BcsAB, they can feature multiple accessory subunits, often indispensable for polysaccharide production. Importantly, the last years mark significant progress in our understanding not only of cellulose polymerization per se but also of the bigger picture of bacterial signaling, secretion system assembly, biofilm formation and host tissue colonization, as well as of structural and functional parallels of this dominant biosynthetic process between the bacterial and eukaryotic domains of life. Here, we review current mechanistic knowledge on bacterial cellulose secretion with focus on the structure, assembly and cooperativity of Bcs secretion system components.
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Affiliation(s)
- Wiem Abidi
- 'Structural Biology of Biofilms' group, European Institute of Chemistry and Biology (IECB), F-33600 Pessac, France.,Université de Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, F-33600 Pessac, France.,École doctorale 'Innovation thérapeutique: du fundamental à l'appliqué' (ITFA), Université Paris-Saclay, 92296, Chatenay-Malabry, France
| | - Lucía Torres-Sánchez
- 'Structural Biology of Biofilms' group, European Institute of Chemistry and Biology (IECB), F-33600 Pessac, France.,Université de Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, F-33600 Pessac, France.,École doctorale 'Innovation thérapeutique: du fundamental à l'appliqué' (ITFA), Université Paris-Saclay, 92296, Chatenay-Malabry, France
| | - Axel Siroy
- 'Structural Biology of Biofilms' group, European Institute of Chemistry and Biology (IECB), F-33600 Pessac, France.,Université de Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, F-33600 Pessac, France
| | - Petya Violinova Krasteva
- 'Structural Biology of Biofilms' group, European Institute of Chemistry and Biology (IECB), F-33600 Pessac, France.,Université de Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, F-33600 Pessac, France
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18
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Bargaz A, Elhaissoufi W, Khourchi S, Benmrid B, Borden KA, Rchiad Z. Benefits of phosphate solubilizing bacteria on belowground crop performance for improved crop acquisition of phosphorus. Microbiol Res 2021; 252:126842. [PMID: 34438221 DOI: 10.1016/j.micres.2021.126842] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 07/31/2021] [Accepted: 08/04/2021] [Indexed: 10/20/2022]
Abstract
Although research on plant growth promoting bacteria began in the 1950s, basic and applied research on bacteria improving use of phosphorus (P) continues to be a priority among many agricultural research institutions. Ultimately, identifying agriculturally beneficial microbes, notably P solubilizing bacteria (PSB), that enhance the efficient use of P supports more sustainable cropping systems and the judicious use of mineral nutrients. In parallel, there is more attention on improving crop root P acquisition of existing soil P pools as well as by increasing the proportion of fertilizer P that is taken up by crops. Today, new lines of research are emerging to investigate the co-optimization of PSB-fertilizer-crop root processes for improved P efficiency and agricultural performance. In this review, we compile and summarize available findings on the beneficial effects of PSB on crop production with a focus on crop P acquisition via root system responses at the structural, functional and transcriptional levels. We discuss the current state of knowledge on the mechanisms of PSB-mediated P availability, both soil- and root-associated, as well as crop uptake via P solubilization, mineralization and mobilization, mainly through the production of organic acids and P-hydrolyzing enzymes, and effects on phytohormone signaling for crop root developement. The systematic changes caused by PSB on crop roots are discussed and contextualized within promising functional trait-based frameworks. We also detail agronomic profitability of P (mineral and organic) and PSB co-application, in amended soils and inoculated crops, establishing the connection between the influence of PSB on agroecosystem production and the impact of P fertilization on microbial diversity and crop functional traits for P acquisition.
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Affiliation(s)
- Adnane Bargaz
- Mohammed VI Polytechnic University, Agrobiosciences Program, Plant & Soil Microbiome Subprogram, Bengurir, 43150, Morocco.
| | - Wissal Elhaissoufi
- Mohammed VI Polytechnic University, Agrobiosciences Program, Plant & Soil Microbiome Subprogram, Bengurir, 43150, Morocco; Cadi Ayyad University, Faculty of Sciences and Techniques, Biology Dep., Marrakech, Morocco
| | - Said Khourchi
- Mohammed VI Polytechnic University, Agrobiosciences Program, Plant & Soil Microbiome Subprogram, Bengurir, 43150, Morocco; University of Liège, Gembloux Agro-Bio Tech, Liège, Belgium
| | - Bouchra Benmrid
- Mohammed VI Polytechnic University, Agrobiosciences Program, Plant & Soil Microbiome Subprogram, Bengurir, 43150, Morocco
| | - Kira A Borden
- University of British Columbia, Faculty of Land and Food Systems, Vancouver, V6T 1Z4, Canada
| | - Zineb Rchiad
- Mohammed VI Polytechnic University, Agrobiosciences Program, Plant & Soil Microbiome Subprogram, Bengurir, 43150, Morocco
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19
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Dillon MM, Ruiz-Bedoya T, Bundalovic-Torma C, Guttman KM, Kwak H, Middleton MA, Wang PW, Horuz S, Aysan Y, Guttman DS. Comparative genomic insights into the epidemiology and virulence of plant pathogenic pseudomonads from Turkey. Microb Genom 2021; 7. [PMID: 34227931 PMCID: PMC8477409 DOI: 10.1099/mgen.0.000585] [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] [Indexed: 12/31/2022] Open
Abstract
Pseudomonas is a highly diverse genus that includes species that cause disease in both plants and animals. Recently, pathogenic pseudomonads from the Pseudomonas syringae and Pseudomonas fluorescens species complexes have caused significant outbreaks in several agronomically important crops in Turkey, including tomato, citrus, artichoke and melon. We characterized 169 pathogenic Pseudomonas strains associated with recent outbreaks in Turkey via multilocus sequence analysis and whole-genome sequencing, then used comparative and evolutionary genomics to characterize putative virulence mechanisms. Most of the isolates are closely related to other plant pathogens distributed among the primary phylogroups of P. syringae, although there are significant numbers of P. fluorescens isolates, which is a species better known as a rhizosphere-inhabiting plant-growth promoter. We found that all 39 citrus blast pathogens cluster in P. syringae phylogroup 2, although strains isolated from the same host do not cluster monophyletically, with lemon, mandarin orange and sweet orange isolates all being intermixed throughout the phylogroup. In contrast, 20 tomato pith pathogens are found in two independent lineages: one in the P. syringae secondary phylogroups, and the other from the P. fluorescens species complex. These divergent pith necrosis strains lack characteristic virulence factors like the canonical tripartite type III secretion system, large effector repertoires and the ability to synthesize multiple bacterial phytotoxins, suggesting they have alternative molecular mechanisms to cause disease. These findings highlight the complex nature of host specificity among plant pathogenic pseudomonads.
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Affiliation(s)
- Marcus M Dillon
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada.,Present address: Department of Biology, University of Toronto at Mississauga, Mississauga, Ontario, Canada
| | - Tatiana Ruiz-Bedoya
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | | | - Kevin M Guttman
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Haejin Kwak
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Maggie A Middleton
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada.,Centre for the Analysis of Genome Evolution and Function, University of Toronto, Toronto, Ontario, Canada
| | - Pauline W Wang
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada.,Centre for the Analysis of Genome Evolution and Function, University of Toronto, Toronto, Ontario, Canada
| | - Sumer Horuz
- Department of Plant Protection, Erciyes University, Kayseri, Turkey
| | - Yesim Aysan
- Department of Plant Protection, University of Çukurova, Adana, Turkey
| | - David S Guttman
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada.,Centre for the Analysis of Genome Evolution and Function, University of Toronto, Toronto, Ontario, Canada
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20
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Wilkes TI, Warner DJ, Edmonds-Brown V, Davies KG, Denholm I. The Tripartite Rhizobacteria-AM Fungal-Host Plant Relationship in Winter Wheat: Impact of Multi-Species Inoculation, Tillage Regime and Naturally Occurring Rhizobacteria Species. PLANTS (BASEL, SWITZERLAND) 2021; 10:1357. [PMID: 34371559 PMCID: PMC8309287 DOI: 10.3390/plants10071357] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 06/28/2021] [Accepted: 07/01/2021] [Indexed: 11/30/2022]
Abstract
Soils and plant root rhizospheres have diverse microorganism profiles. Components of this naturally occurring microbiome, arbuscular mycorrhizal (AM) fungi and plant growth promoting rhizobacteria (PGPR), may be beneficial to plant growth. Supplementary application to host plants of AM fungi and PGPR either as single species or multiple species inoculants has the potential to enhance this symbiotic relationship further. Single species interactions have been described; the nature of multi-species tripartite relationships between AM fungi, PGPR and the host plant require further scrutiny. The impact of select Bacilli spp. rhizobacteria and the AM fungus Rhizophagus intraradices as both single and combined inoculations (PGPR[i] and AMF[i]) within field extracted arable soils of two tillage treatments, conventional soil inversion (CT) and zero tillage (ZT) at winter wheat growth stages GS30 and GS39 have been conducted. The naturally occurring soil borne species (PGPR[s] and AMF[s]) have been determined by qPCR analysis. Significant differences (p < 0.05) were evident between inocula treatments and the method of seedbed preparation. A positive impact on wheat plant growth was noted for B. amyloliquefaciens applied as both a single inoculant (PGPR[i]) and in combination with R. intraradices (PGPR[i] + AMF[i]); however, the two treatments did not differ significantly from each other. The findings are discussed in the context of the inocula applied and the naturally occurring soil borne PGPR[s] present in the field extracted soil under each method of tillage.
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Affiliation(s)
- Thomas I. Wilkes
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, College Lane Campus, University of Hertfordshire, Hatfield, Hertfordshire AL10 9AB, UK; (V.E.-B.); (K.G.D.); (I.D.)
| | - Douglas J. Warner
- Agriculture and Environment Research Unit, School of Life and Medical Sciences, College Lane Campus, University of Hertfordshire, Hatfield, Hertfordshire AL10 9AB, UK;
| | - Veronica Edmonds-Brown
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, College Lane Campus, University of Hertfordshire, Hatfield, Hertfordshire AL10 9AB, UK; (V.E.-B.); (K.G.D.); (I.D.)
| | - Keith G. Davies
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, College Lane Campus, University of Hertfordshire, Hatfield, Hertfordshire AL10 9AB, UK; (V.E.-B.); (K.G.D.); (I.D.)
| | - Ian Denholm
- Department of Psychology, Sport and Geography, School of Life and Medical Sciences, College Lane Campus, University of Hertfordshire, Hatfield, Hertfordshire AL10 9AB, UK; (V.E.-B.); (K.G.D.); (I.D.)
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21
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Suresh P, Varathraju G, Shanmugaiah V, Almaary KS, Elbadawi YB, Mubarak A. Partial purification and characterization of 2, 4-diacetylphloroglucinol producing Pseudomonas fluorescens VSMKU3054 against bacterial wilt disease of tomato. Saudi J Biol Sci 2021; 28:2155-2167. [PMID: 33911932 PMCID: PMC8071909 DOI: 10.1016/j.sjbs.2021.02.073] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 02/17/2021] [Accepted: 02/22/2021] [Indexed: 11/27/2022] Open
Abstract
We find out the antimicrobial potential of partially purified 2,4-diacetylphloroglucinol (DAPG) against Ralstonia solanacearum and fungal plant pathogens isolated from tomato rhizobacterium Pseudomonas fluorescens VSMKU3054. The present study is mainly focused on the control of wilt disease of tomato by our isolate VSMKU3054 and DAPG. The cell free culture filtrate of P. fluorescens VSMKU3054 was significantly arrested the growth of R. solanacearum and fungal pathogens such as Rhizoctonia solani, Sclerotium rolfsii, Macrophomina phaseolina and Fusarium oxysporum compared to control. The existence of DAPG from the crude metabolites of P. fluorescens VSMKU3054 was confirmed on TLC with Rf value 0.34, which is coincide with that of authentic phloroglucinol. The partially purified DAPG exhibited much higher activity against R. solanacearum at 30 µg/ml than the fungal plant pathogens compared to control. The antimicrobial partially purified compound was identified as DAPG by UV, FT-IR and GC-MS analysis. The percentage of live cells of R. solanacearum when supplemented with DAPG at 30 µg/ml, significantly controlled the living nature of R. solanacearum up to 68% compared to tetracycline and universal control observed under high content screening analysis. The selected isolate P. fluorescens VSMKU3054 and DAPG significantly controlled wilt disease of tomato up to 59.5% and 42.12% on 3rd and 7th days compared to positive and negative control by detached leaf assay. Further, in silico analysis revealed that high interaction of DAPG encoding protease with lectin which is associated with R. solanacearum. Based on our findings, we confirmed that P. fluorescens VSMKU3054 and DAPG could be used a potential bio inoculants for the management of bacterial wilt disease of tomato.
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Affiliation(s)
- Perumal Suresh
- Department of Microbial Technology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625 021, Tamil Nadu, India
| | - Govintharaj Varathraju
- Department of Microbial Technology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625 021, Tamil Nadu, India
| | - Vellasamy Shanmugaiah
- Department of Microbial Technology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625 021, Tamil Nadu, India
| | - Khalid S Almaary
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. 2455, Riyadh 11451, Saudi Arabia
| | - Yahya B Elbadawi
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. 2455, Riyadh 11451, Saudi Arabia
| | - Ayman Mubarak
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. 2455, Riyadh 11451, Saudi Arabia
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22
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Rhizosphere Microbiome Cooperations: Strategies for Sustainable Crop Production. Curr Microbiol 2021; 78:1069-1085. [PMID: 33611628 DOI: 10.1007/s00284-021-02375-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 02/05/2021] [Indexed: 01/29/2023]
Abstract
Interactions between microorganisms and host plants determine the growth and development as well as the health of the host plant. Various microbial groups inhabit the rhizosphere, each with its peculiar function. The survival of each microbial group depends to a large extent on its ability to colonize the plant root and outcompete the native organisms. The role of the rhizospheric microbiome in enhancing plant growth has not been fully maximized. An understanding of the complexities of microbial interactions and factors affecting their assembly in the community is necessary to benefit maximally from the cooperations of various microbial communities for sustainable crop production. In this review, we outline the various organisms associated with the plant rhizosphere with emphasis on their interactions and mechanisms used in plant growth promotion.
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23
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Vandana UK, Rajkumari J, Singha LP, Satish L, Alavilli H, Sudheer PD, Chauhan S, Ratnala R, Satturu V, Mazumder PB, Pandey P. The Endophytic Microbiome as a Hotspot of Synergistic Interactions, with Prospects of Plant Growth Promotion. BIOLOGY 2021; 10:101. [PMID: 33535706 PMCID: PMC7912845 DOI: 10.3390/biology10020101] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 01/28/2021] [Accepted: 01/29/2021] [Indexed: 12/16/2022]
Abstract
The plant root is the primary site of interaction between plants and associated microorganisms and constitutes the main components of plant microbiomes that impact crop production. The endophytic bacteria in the root zone have an important role in plant growth promotion. Diverse microbial communities inhabit plant root tissues, and they directly or indirectly promote plant growth by inhibiting the growth of plant pathogens, producing various secondary metabolites. Mechanisms of plant growth promotion and response of root endophytic microorganisms for their survival and colonization in the host plants are the result of complex plant-microbe interactions. Endophytic microorganisms also assist the host to sustain different biotic and abiotic stresses. Better insights are emerging for the endophyte, such as host plant interactions due to advancements in 'omic' technologies, which facilitate the exploration of genes that are responsible for plant tissue colonization. Consequently, this is informative to envisage putative functions and metabolic processes crucial for endophytic adaptations. Detection of cell signaling molecules between host plants and identification of compounds synthesized by root endophytes are effective means for their utilization in the agriculture sector as biofertilizers. In addition, it is interesting that the endophytic microorganism colonization impacts the relative abundance of indigenous microbial communities and suppresses the deleterious microorganisms in plant tissues. Natural products released by endophytes act as biocontrol agents and inhibit pathogen growth. The symbiosis of endophytic bacteria and arbuscular mycorrhizal fungi (AMF) affects plant symbiotic signaling pathways and root colonization patterns and phytohormone synthesis. In this review, the potential of the root endophytic community, colonization, and role in the improvement of plant growth has been explained in the light of intricate plant-microbe interactions.
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Affiliation(s)
- Udaya Kumar Vandana
- Department of Biotechnology, Assam University Silchar, Assam 788011, India; (U.K.V.); (P.B.M.)
| | - Jina Rajkumari
- Department of Microbiology, Assam University Silchar, Assam 788011, India; (J.R.); (L.P.S.)
| | - L. Paikhomba Singha
- Department of Microbiology, Assam University Silchar, Assam 788011, India; (J.R.); (L.P.S.)
| | - Lakkakula Satish
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering and the Ilse Katz Center for Meso and Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel;
- The Albert Katz International School for Desert Studies, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel
| | - Hemasundar Alavilli
- Department of Biochemistry and Molecular Biology, College of Medicine, Korea Molecular Medicine and Nutrition Research Institute, Korea University, Seoul 02841, Korea;
| | - Pamidimarri D.V.N. Sudheer
- Amity Institute of Biotechnology, Amity University Chhattisgarh, Raipur 493225, India; (P.D.V.N.S.); (S.C.)
| | - Sushma Chauhan
- Amity Institute of Biotechnology, Amity University Chhattisgarh, Raipur 493225, India; (P.D.V.N.S.); (S.C.)
| | - Rambabu Ratnala
- TATA Institute for Genetics and Society, Bangalore 560065, India;
| | - Vanisri Satturu
- Institute of Biotechnology, Professor Jayashankar Telangana State Agricultural University, Rajendranagar, Hyderabad 500030, India;
| | - Pranab Behari Mazumder
- Department of Biotechnology, Assam University Silchar, Assam 788011, India; (U.K.V.); (P.B.M.)
| | - Piyush Pandey
- Department of Microbiology, Assam University Silchar, Assam 788011, India; (J.R.); (L.P.S.)
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Pathma J, Kennedy RK, Bhushan LS, Shankar BK, Thakur K. Microbial Biofertilizers and Biopesticides: Nature’s Assets Fostering Sustainable Agriculture. RECENT DEVELOPMENTS IN MICROBIAL TECHNOLOGIES 2021. [DOI: 10.1007/978-981-15-4439-2_2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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25
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Cesa-Luna C, Baez A, Aguayo-Acosta A, Llano-Villarreal RC, Juárez-González VR, Gaytán P, Bustillos-Cristales MDR, Rivera-Urbalejo A, Muñoz-Rojas J, Quintero-Hernández V. Growth inhibition of pathogenic microorganisms by Pseudomonas protegens EMM-1 and partial characterization of inhibitory substances. PLoS One 2020; 15:e0240545. [PMID: 33057351 PMCID: PMC7561207 DOI: 10.1371/journal.pone.0240545] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 09/28/2020] [Indexed: 11/18/2022] Open
Abstract
The bacterial strain, EMM-1, was isolated from the rhizosphere of red maize ("Rojo Criollo") and identified as Pseudomonas protegens EMM-1 based on phylogenetic analysis of 16S rDNA, rpoB, rpoD, and gyrB gene sequences. We uncovered genes involved in the production of antimicrobial compounds like 2,4-diacetylphloroglucinol (2,4-DAPG), pyoluteorin, and lectin-like bacteriocins. These antimicrobial compounds are also produced by other fluorescent pseudomonads alike P. protegens. Double-layer agar assay showed that P. protegens EMM-1 inhibited the growth of several multidrug-resistant (MDR) bacteria, especially clinical isolates of the genera Klebsiella and β-hemolytic Streptococcus. This strain also displayed inhibitory effects against diverse fungi, such as Aspergillus, Botrytis, and Fusarium. Besides, a crude extract of inhibitory substances secreted into agar was obtained after the cold-leaching process, and physicochemical characterization was performed. The partially purified inhibitory substances produced by P. protegens EMM-1 inhibited the growth of Streptococcus sp. and Microbacterium sp., but no inhibitory effect was noted for other bacterial or fungal strains. The molecular weight determined after ultrafiltration was between 3 and 10 kDa. The inhibitory activity was thermally stable up to 60°C (but completely lost at 100°C), and the inhibitory activity remained active in a wide pH range (from 3 to 9). After treatment with a protease from Bacillus licheniformis, the inhibitory activity was decreased by 90%, suggesting the presence of proteic natural compounds. All these findings suggested that P. protegens EMM-1 is a potential source of antimicrobials to be used against pathogens for humans and plants.
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Affiliation(s)
- Catherine Cesa-Luna
- Ecology and Survival of Microorganisms Group (ESMG), Laboratorio de Ecología Molecular Microbiana (LEMM), Centro de Investigaciones en Ciencias Microbiológicas (CICM), Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, Pue., México
| | - Antonino Baez
- Ecology and Survival of Microorganisms Group (ESMG), Laboratorio de Ecología Molecular Microbiana (LEMM), Centro de Investigaciones en Ciencias Microbiológicas (CICM), Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, Pue., México
| | - Alberto Aguayo-Acosta
- Department of Microbiology and Immunology, Biological Sciences Faculty, Universidad Autónoma de Nuevo León, Ciudad Universitaria, San Nicolás de la Garza, Nuevo León, México
| | - Roberto Carlos Llano-Villarreal
- Ecology and Survival of Microorganisms Group (ESMG), Laboratorio de Ecología Molecular Microbiana (LEMM), Centro de Investigaciones en Ciencias Microbiológicas (CICM), Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, Pue., México
| | - Víctor Rivelino Juárez-González
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Paul Gaytán
- Unidad de Síntesis y Secuenciación de ADN, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - María del Rocío Bustillos-Cristales
- Ecology and Survival of Microorganisms Group (ESMG), Laboratorio de Ecología Molecular Microbiana (LEMM), Centro de Investigaciones en Ciencias Microbiológicas (CICM), Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, Pue., México
| | - América Rivera-Urbalejo
- Ecology and Survival of Microorganisms Group (ESMG), Laboratorio de Ecología Molecular Microbiana (LEMM), Centro de Investigaciones en Ciencias Microbiológicas (CICM), Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, Pue., México
- Facultad de Estomatología, BUAP, Puebla, Pue., México
| | - Jesús Muñoz-Rojas
- Ecology and Survival of Microorganisms Group (ESMG), Laboratorio de Ecología Molecular Microbiana (LEMM), Centro de Investigaciones en Ciencias Microbiológicas (CICM), Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, Pue., México
| | - Verónica Quintero-Hernández
- Ecology and Survival of Microorganisms Group (ESMG), Laboratorio de Ecología Molecular Microbiana (LEMM), Centro de Investigaciones en Ciencias Microbiológicas (CICM), Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, Pue., México
- CONACYT–ESMG, LEMM, CICM, IC-BUAP, Puebla, Pue., México
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26
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Role of Biocontrol Agents in Management of Corm Rot of Saffron Caused by Fusarium oxysporum. AGRONOMY-BASEL 2020. [DOI: 10.3390/agronomy10091398] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Saffron (Crocus sativus L.) is considered as one of the most expensive spices. Fusarium corm rot of saffron, caused by Fusarium oxysporum, is known to cause severe yield losses worldwide. In the present study, efficacy of biocontrol agents (Trichoderma asperellum, Pseudomonas fluorescens, Pseudomonas aeruginosa, Pseudomonas putida, Bacillus stratosphericus, Bacillus pumilus, and Bacillus subtilis) along with a chemical fungicide, carbendazim, was evaluated for managing the corm rot of saffron. Under in vitro conditions, using dual culture and poison food techniques on potato dextrose agar, T. asperellum and carbendazim significantly reduced the mycelial growth of the pathogen F. oxysporum, with the inhibition of 62.76 and 60.27%, respectively, compared with control. Under field conditions, dipping of saffron corms in carbendazim and T. asperellum exhibited maximum reduction of 82.77 and 77.84%, respectively, in the disease incidence, during the first year of experiment. However, during the second year, maximum reduction in the incidence of corm rot (68.63%) was recorded with the T. asperellum. Moreover, the population density of F. oxysporum was also significantly reduced by 60 and 80.19% while using T. asperellum after 75 and 260 days of sowing of saffron corms, compared to its population before planting of corms. In case of growth promotion traits, such as sprouting and flowering, biocontrol treatments reduced the number of days (average) of sprouting and flower emergence after sowing, compared to control.
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Rieusset L, Rey M, Muller D, Vacheron J, Gerin F, Dubost A, Comte G, Prigent-Combaret C. Secondary metabolites from plant-associated Pseudomonas are overproduced in biofilm. Microb Biotechnol 2020; 13:1562-1580. [PMID: 33000552 PMCID: PMC7415375 DOI: 10.1111/1751-7915.13598] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 04/29/2020] [Accepted: 04/30/2020] [Indexed: 02/06/2023] Open
Abstract
Plant rhizosphere soil houses complex microbial communities in which microorganisms are often involved in intraspecies as well as interspecies and inter-kingdom signalling networks. Some members of these networks can improve plant health thanks to an important diversity of bioactive secondary metabolites. In this competitive environment, the ability to form biofilms may provide major advantages to microorganisms. With the aim of highlighting the impact of bacterial lifestyle on secondary metabolites production, we performed a metabolomic analysis on four fluorescent Pseudomonas strains cultivated in planktonic and biofilm colony conditions. The untargeted metabolomic analysis led to the detection of hundreds of secondary metabolites in culture extracts. Comparison between biofilm and planktonic conditions showed that bacterial lifestyle is a key factor influencing Pseudomonas metabolome. More than 50% of the detected metabolites were differentially produced according to planktonic or biofilm lifestyles, with the four Pseudomonas strains overproducing several secondary metabolites in biofilm conditions. In parallel, metabolomic analysis associated with genomic prediction and a molecular networking approach enabled us to evaluate the impact of bacterial lifestyle on chemically identified secondary metabolites, more precisely involved in microbial interactions and plant-growth promotion. Notably, this work highlights the major effect of biofilm lifestyle on acyl-homoserine lactone and phenazine production in P. chlororaphis strains.
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Affiliation(s)
- Laura Rieusset
- CNRS UMR-5557, INRAe UMR-1418, Ecologie Microbienne, VetAgroSup, Université de Lyon, Université Claude Bernard Lyon1, 43 Boulevard du 11 novembre 1918, Villeurbanne, 69622, France
| | - Marjolaine Rey
- CNRS UMR-5557, INRAe UMR-1418, Ecologie Microbienne, VetAgroSup, Université de Lyon, Université Claude Bernard Lyon1, 43 Boulevard du 11 novembre 1918, Villeurbanne, 69622, France
| | - Daniel Muller
- CNRS UMR-5557, INRAe UMR-1418, Ecologie Microbienne, VetAgroSup, Université de Lyon, Université Claude Bernard Lyon1, 43 Boulevard du 11 novembre 1918, Villeurbanne, 69622, France
| | - Jordan Vacheron
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, 1015, Switzerland
| | - Florence Gerin
- CNRS UMR-5557, INRAe UMR-1418, Ecologie Microbienne, VetAgroSup, Université de Lyon, Université Claude Bernard Lyon1, 43 Boulevard du 11 novembre 1918, Villeurbanne, 69622, France
| | - Audrey Dubost
- CNRS UMR-5557, INRAe UMR-1418, Ecologie Microbienne, VetAgroSup, Université de Lyon, Université Claude Bernard Lyon1, 43 Boulevard du 11 novembre 1918, Villeurbanne, 69622, France
| | - Gilles Comte
- CNRS UMR-5557, INRAe UMR-1418, Ecologie Microbienne, VetAgroSup, Université de Lyon, Université Claude Bernard Lyon1, 43 Boulevard du 11 novembre 1918, Villeurbanne, 69622, France
| | - Claire Prigent-Combaret
- CNRS UMR-5557, INRAe UMR-1418, Ecologie Microbienne, VetAgroSup, Université de Lyon, Université Claude Bernard Lyon1, 43 Boulevard du 11 novembre 1918, Villeurbanne, 69622, France
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Bhat MA, Kumar V, Bhat MA, Wani IA, Dar FL, Farooq I, Bhatti F, Koser R, Rahman S, Jan AT. Mechanistic Insights of the Interaction of Plant Growth-Promoting Rhizobacteria (PGPR) With Plant Roots Toward Enhancing Plant Productivity by Alleviating Salinity Stress. Front Microbiol 2020; 11:1952. [PMID: 32973708 PMCID: PMC7468593 DOI: 10.3389/fmicb.2020.01952] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 07/24/2020] [Indexed: 11/20/2022] Open
Abstract
Agriculture plays an important role in a country's economy. The sector is challenged by many stresses, which led to huge loss in plant productivity worldwide. The ever-increasing population, rapid urbanization with shrinking agricultural lands, dramatic change in climatic conditions, and extensive use of agrochemicals in agricultural practices that caused environmental disturbances confront mankind of escalating problems of food security and sustainability in agriculture. Escalating environmental problems and global hunger have led to the development and adoption of genetic engineering and other conventional plant breeding approaches in developing stress-tolerant varieties of crops. However, these approaches have drawn flaws in their adoption as the process of generating tolerant varieties takes months to years in bringing the technology from the lab to the field. Under such scenario, sustainable and climate-smart agricultural practices that avail bacterial usage open the avenues in fulfilling the incessant demand for food for the global population. Ensuring stability on economic fronts, bacteria minimizes plant salt uptake by trapping ions in their exopolysaccharide matrix besides checking the expression of Na+/H+ and high-affinity potassium transporters. Herein we describe information on salinity stress and its effect on plant health as well as strategies adopted by plant growth-promoting rhizobacteria (PGPR) in helping plants to overcome salinity stress and in mitigating loss in overall plant productivity. It is believed that acquisition of advanced knowledge of plant-beneficial PGPR will help in devising strategies for sustainable, environment-friendly, and climate-smart agricultural technologies for adoption in agriculture to overcome the constrained environmental conditions.
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Affiliation(s)
- Mujtaba Aamir Bhat
- Department of Botany, School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, India
| | - Vijay Kumar
- Department of Biotechnology, Yeungnam University, Gyeongsan, South Korea
| | - Mudasir Ahmad Bhat
- Department of Biotechnology, School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, India
| | - Ishfaq Ahmad Wani
- Department of Botany, School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, India
| | - Farhana Latief Dar
- Department of Botany, School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, India
| | - Iqra Farooq
- Department of Botany, School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, India
| | - Farha Bhatti
- Department of Botany, School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, India
| | - Rubina Koser
- Department of Microbiology, School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, India
| | - Safikur Rahman
- Department of Botany, Munshi Singh College, Babasaheb Bhimrao Ambedkar Bihar University, Muzaffarpur, India
| | - Arif Tasleem Jan
- Department of Botany, School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, India
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Meena M, Swapnil P, Divyanshu K, Kumar S, Harish, Tripathi YN, Zehra A, Marwal A, Upadhyay RS. PGPR-mediated induction of systemic resistance and physiochemical alterations in plants against the pathogens: Current perspectives. J Basic Microbiol 2020; 60:828-861. [PMID: 32815221 DOI: 10.1002/jobm.202000370] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/28/2020] [Accepted: 08/02/2020] [Indexed: 12/14/2022]
Abstract
Plant growth-promoting rhizobacteria (PGPR) are diverse groups of plant-associated microorganisms, which can reduce the severity or incidence of disease during antagonism among bacteria and soil-borne pathogens, as well as by influencing a systemic resistance to elicit defense response in host plants. An amalgamation of various strains of PGPR has improved the efficacy by enhancing the systemic resistance opposed to various pathogens affecting the crop. Many PGPR used with seed treatment causes structural improvement of the cell wall and physiological/biochemical changes leading to the synthesis of proteins, peptides, and chemicals occupied in plant defense mechanisms. The major determinants of PGPR-mediated induced systemic resistance (ISR) are lipopolysaccharides, lipopeptides, siderophores, pyocyanin, antibiotics 2,4-diacetylphoroglucinol, the volatile 2,3-butanediol, N-alkylated benzylamine, and iron-regulated compounds. Many PGPR inoculants have been commercialized and these inoculants consequently aid in the improvement of crop growth yield and provide effective reinforcement to the crop from disease, whereas other inoculants are used as biofertilizers for native as well as crops growing at diverse extreme habitat and exhibit multifunctional plant growth-promoting attributes. A number of applications of PGPR formulation are needed to maintain the resistance levels in crop plants. Several microarray-based studies have been done to identify the genes, which are associated with PGPR-induced systemic resistance. Identification of these genes associated with ISR-mediating disease suppression and biochemical changes in the crop plant is one of the essential steps in understanding the disease resistance mechanisms in crops. Therefore, in this review, we discuss the PGPR-mediated innovative methods, focusing on the mode of action of compounds authorized that may be significant in the development contributing to enhance plant growth, disease resistance, and serve as an efficient bioinoculants for sustainable agriculture. The review also highlights current research progress in this field with a special emphasis on challenges, limitations, and their environmental and economic advantages.
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Affiliation(s)
- Mukesh Meena
- Laboratory of Phytopathology and Microbial Biotechnology, Department of Botany, Mohanlal Sukhadia University, Udaipur, Rajasthan, India.,Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Prashant Swapnil
- Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India.,Department of Botany, Acharya Narendra Dev College, University of Delhi, New Delhi, India
| | - Kumari Divyanshu
- Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Sunil Kumar
- Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Harish
- Plant Biotechnology Laboratory, Department of Botany, Mohanlal Sukhadia University, Udaipur, Rajasthan, India
| | - Yashoda Nandan Tripathi
- Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Andleeb Zehra
- Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Avinash Marwal
- Department of Biotechnology, Vigyan Bhawan-Block B, New Campus, Mohanlal Sukhadia University, Udaipur, Rajasthan, India
| | - Ram Sanmukh Upadhyay
- Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu University, Varanasi, India
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de la Torre-Hernández ME, Salinas-Virgen LI, Aguirre-Garrido JF, Fernández-González AJ, Martínez-Abarca F, Montiel-Lugo D, Ramírez-Saad HC. Composition, Structure, and PGPR Traits of the Rhizospheric Bacterial Communities Associated With Wild and Cultivated Echinocactus platyacanthus and Neobuxbaumia polylopha. Front Microbiol 2020; 11:1424. [PMID: 32676064 PMCID: PMC7333311 DOI: 10.3389/fmicb.2020.01424] [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: 12/07/2019] [Accepted: 06/02/2020] [Indexed: 02/01/2023] Open
Abstract
The Queretaro semi-desert in central Mexico is the most southern extension of the Chihuahua desert. This semi-arid zone shelters a vast cactus diversity with many endemic species. Currently, two cacti species from this semi-desert namely, Echinocactus platyacanthus and Neobuxbaumia polylopha are under a threat to their survival. So far, there are no reports on the bacterial communities associated with these plants. In this study, we assessed the structure and diversity of the rhizospheric bacterial communities associated with Echinocactus platyacanthus and Neobuxbaumia polylopha growing in wild and cultivated conditions. Samples of E. platyacanthus were also approached with culture-based methods in search of isolates with plant growth promoting abilities. Metagenomic DNA was extracted from rhizospheric samples and used for Illumina sequencing of the 16S rRNA gene. α-diversity and amplicon sequence variant (ASV) richness were higher in both groups of E. platyacanthus samples. All samples accounted for 14 phyla, and the major 6 were common to all treatments. The dominant phyla in all four sample groups were Actinobacteria and Proteobacteria. Analysis at family and genus levels showed association patterns with the cultivated samples from both species grouping together, while the wild samples of each cactus species were grouping apart. High abundance values of Rubrobacteraceae (15.9-18.4%) were a characteristic feature of wild E. platyacanthus samples. In total, 2,227 ASVs were scored in all 12 rhizospheric samples where E. platyacanthus samples showed higher richness with 1,536 ASVs. Regarding the growing conditions, both groups of cultivated samples were also richer accounting for 743 and 615 ASVs for E. platyacanthus and N. polylopha, respectively. The isolates from E. platyacanthus rhizosphere were mainly assigned to Bacilli and Gammaproteobacteria. In total 35 strains were assayed for PGPR traits (IAA and siderophore production, phosphate solubilization, and fungal growth inhibition). Strains obtained from plants growing in the wild displayed better PGPR characteristics, stressing that naturally occurring wild plants are a source of bacteria with diverse metabolic activities, which can be very important players in the adaptation of cacti to their natural environments.
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Affiliation(s)
| | - Leilani I. Salinas-Virgen
- Maestría en Ciencias Agropecuarias, Universidad Autónoma Metropolitana-Xochimilco, Mexico City, Mexico
| | - J. Félix Aguirre-Garrido
- Departamento de Ciencias Ambientales, Universidad Autónoma Metropolitana-Lerma, Estado de México Mexico
| | - Antonio J. Fernández-González
- Grupo de Ecología Genética, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Francisco Martínez-Abarca
- Grupo de Ecología Genética, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Daniel Montiel-Lugo
- Maestría en Ciencias Agropecuarias, Universidad Autónoma Metropolitana-Xochimilco, Mexico City, Mexico
| | - Hugo C. Ramírez-Saad
- Departamento Sistemas Biológicos, Universidad Autónoma Metropolitana-Xochimilco, Mexico City, Mexico
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Daura-Pich O, Hernández I, Pinyol-Escala L, Lara JM, Martínez-Servat S, Fernández C, López-García B. No antibiotic and toxic metabolites produced by the biocontrol agent Pseudomonas putida strain B2017. FEMS Microbiol Lett 2020; 367:5826813. [DOI: 10.1093/femsle/fnaa075] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 04/28/2020] [Indexed: 12/30/2022] Open
Abstract
ABSTRACTPseudomonas putida and closely-related species such as Pseudomonas fluorescens and Pseudomonas brassicacearum have been reported as potential biocontrol agents and plant growth-promoters. Recently, we have described the biocontrol activity of P. putida B2017 against several phytopathogens of agricultural relevance. In this study, its ability to produce potential antibiotic / toxic metabolites was assessed by functional, chromatography-mass spectrometry and genomic analysis. Our results show that B2017 is not able to synthesize surfactants and common antibiotics produced by Pseudomonas spp., i.e. pyrrolnitrin, 2,4-diacetylphloroglucinol, pyoluteorin and pyocyanin, but it produces pyoverdine, a siderophore which is involved in its biocontrol activity. The non-production of other metabolites, such as cyanide, safracin, promysalin and lipopeptides between others, is also discussed. Our data suggest that the mode of action of B2017 is not mainly due to the production of antimicrobial / toxic metabolites. Moreover, these features make P. putida B2017 a promising biocontrol microorganism for plant protection without side effects on environment, non-target organisms and human health.
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Affiliation(s)
- Oriol Daura-Pich
- Futureco Bioscience S. A., Avinguda del Cadí 19–23, 08799 Olérdola (Barcelona), Spain
| | - Iker Hernández
- Futureco Bioscience S. A., Avinguda del Cadí 19–23, 08799 Olérdola (Barcelona), Spain
| | - Lola Pinyol-Escala
- Futureco Bioscience S. A., Avinguda del Cadí 19–23, 08799 Olérdola (Barcelona), Spain
| | - Jose M Lara
- Futureco Bioscience S. A., Avinguda del Cadí 19–23, 08799 Olérdola (Barcelona), Spain
| | - Sonia Martínez-Servat
- Futureco Bioscience S. A., Avinguda del Cadí 19–23, 08799 Olérdola (Barcelona), Spain
| | - Carolina Fernández
- Futureco Bioscience S. A., Avinguda del Cadí 19–23, 08799 Olérdola (Barcelona), Spain
| | - Belén López-García
- Futureco Bioscience S. A., Avinguda del Cadí 19–23, 08799 Olérdola (Barcelona), Spain
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Pseudomonas taiwanensis (MTCC11631) mediated induction of systemic resistance in Anthurium andreanum L against blight disease and visualisation of defence related secondary metabolites using confocal laser scanning microscopy. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2020. [DOI: 10.1016/j.bcab.2020.101561] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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33
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Greenwood M, Locke JC. The circadian clock coordinates plant development through specificity at the tissue and cellular level. CURRENT OPINION IN PLANT BIOLOGY 2020; 53:65-72. [PMID: 31783323 DOI: 10.1016/j.pbi.2019.09.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 09/20/2019] [Accepted: 09/23/2019] [Indexed: 05/27/2023]
Abstract
The circadian clock is a genetic circuit that allows organisms to anticipate daily events caused by the rotation of the Earth. The plant clock regulates physiology at multiple scales, from cell division to ecosystem-scale interactions. It is becoming clear that rather than being a single perfectly synchronised timer throughout the plant, the clock can be sensitive to different cues, run at different speeds, and drive distinct processes in different cell types and tissues. This flexibility may help the plant clock to regulate such a range of developmental and physiological processes. In this review, using examples from the literature, we describe how the clock regulates development at multiple scales and discuss how the clock might allow local flexibility in regulation whilst remaining coordinated across the plant.
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Affiliation(s)
- Mark Greenwood
- Sainsbury Laboratory, University of Cambridge, Bateman Street, Cambridge, UK; Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, UK
| | - James Cw Locke
- Sainsbury Laboratory, University of Cambridge, Bateman Street, Cambridge, UK.
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Towards a Sustainable Agriculture: Strategies Involving Phytoprotectants against Salt Stress. AGRONOMY-BASEL 2020. [DOI: 10.3390/agronomy10020194] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Salinity is one of the main constraints for agriculture productivity worldwide. This important abiotic stress has worsened in the last 20 years due to the increase in water demands in arid and semi-arid areas. In this context, increasing tolerance of crop plants to salt stress is needed to guarantee future food supply to a growing population. This review compiles knowledge on the use of phytoprotectants of microbial origin (arbuscular mycorrhizal fungi and plant growth-promoting rhizobacteria), osmoprotectants, melatonin, phytohormones and antioxidant metabolism-related compounds as alleviators of salt stress in numerous plant species. Phytoprotectants are discussed in detail, including their nature, applicability, and role in the plant in terms of physiological and phenotype effects. As a result, increased crop yield and crop quality can be achieved, which in turn positively impact food security. Herein, efforts from academic and industrial sectors should focus on defining the treatment conditions and plant-phytoprotectant associations providing higher benefits.
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de la Torre-Hernández ME, Salinas-Virgen LI, Aguirre-Garrido JF, Fernández-González AJ, Martínez-Abarca F, Montiel-Lugo D, Ramírez-Saad HC. Composition, Structure, and PGPR Traits of the Rhizospheric Bacterial Communities Associated With Wild and Cultivated Echinocactus platyacanthus and Neobuxbaumia polylopha. Front Microbiol 2020. [PMID: 32676064 DOI: 10.3389/fmicb.2020.01424/bibtex] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023] Open
Abstract
The Queretaro semi-desert in central Mexico is the most southern extension of the Chihuahua desert. This semi-arid zone shelters a vast cactus diversity with many endemic species. Currently, two cacti species from this semi-desert namely, Echinocactus platyacanthus and Neobuxbaumia polylopha are under a threat to their survival. So far, there are no reports on the bacterial communities associated with these plants. In this study, we assessed the structure and diversity of the rhizospheric bacterial communities associated with Echinocactus platyacanthus and Neobuxbaumia polylopha growing in wild and cultivated conditions. Samples of E. platyacanthus were also approached with culture-based methods in search of isolates with plant growth promoting abilities. Metagenomic DNA was extracted from rhizospheric samples and used for Illumina sequencing of the 16S rRNA gene. α-diversity and amplicon sequence variant (ASV) richness were higher in both groups of E. platyacanthus samples. All samples accounted for 14 phyla, and the major 6 were common to all treatments. The dominant phyla in all four sample groups were Actinobacteria and Proteobacteria. Analysis at family and genus levels showed association patterns with the cultivated samples from both species grouping together, while the wild samples of each cactus species were grouping apart. High abundance values of Rubrobacteraceae (15.9-18.4%) were a characteristic feature of wild E. platyacanthus samples. In total, 2,227 ASVs were scored in all 12 rhizospheric samples where E. platyacanthus samples showed higher richness with 1,536 ASVs. Regarding the growing conditions, both groups of cultivated samples were also richer accounting for 743 and 615 ASVs for E. platyacanthus and N. polylopha, respectively. The isolates from E. platyacanthus rhizosphere were mainly assigned to Bacilli and Gammaproteobacteria. In total 35 strains were assayed for PGPR traits (IAA and siderophore production, phosphate solubilization, and fungal growth inhibition). Strains obtained from plants growing in the wild displayed better PGPR characteristics, stressing that naturally occurring wild plants are a source of bacteria with diverse metabolic activities, which can be very important players in the adaptation of cacti to their natural environments.
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Affiliation(s)
| | - Leilani I Salinas-Virgen
- Maestría en Ciencias Agropecuarias, Universidad Autónoma Metropolitana-Xochimilco, Mexico City, Mexico
| | - J Félix Aguirre-Garrido
- Departamento de Ciencias Ambientales, Universidad Autónoma Metropolitana-Lerma, Estado de México Mexico
| | - Antonio J Fernández-González
- Grupo de Ecología Genética, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Francisco Martínez-Abarca
- Grupo de Ecología Genética, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Daniel Montiel-Lugo
- Maestría en Ciencias Agropecuarias, Universidad Autónoma Metropolitana-Xochimilco, Mexico City, Mexico
| | - Hugo C Ramírez-Saad
- Departamento Sistemas Biológicos, Universidad Autónoma Metropolitana-Xochimilco, Mexico City, Mexico
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In vitro Biofilm Development and Enhanced Rhizosphere Colonization of Triticum aestivum by Fluorescent Pseudomonas sp. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2019. [DOI: 10.22207/jpam.13.3.14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Nelkner J, Tejerizo GT, Hassa J, Lin TW, Witte J, Verwaaijen B, Winkler A, Bunk B, Spröer C, Overmann J, Grosch R, Pühler A, Schlüter AA. Genetic Potential of the Biocontrol Agent Pseudomonas brassicacearum (Formerly P. trivialis) 3Re2-7 Unraveled by Genome Sequencing and Mining, Comparative Genomics and Transcriptomics. Genes (Basel) 2019; 10:E601. [PMID: 31405015 PMCID: PMC6722718 DOI: 10.3390/genes10080601] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 08/02/2019] [Accepted: 08/06/2019] [Indexed: 01/17/2023] Open
Abstract
The genus Pseudomonas comprises many known plant-associated microbes with plant growth promotion and disease suppression properties. Genome-based studies allow the prediction of the underlying mechanisms using genome mining tools and the analysis of the genes unique for a strain by implementing comparative genomics. Here, we provide the genome sequence of the strain Pseudomonas brassicacearum 3Re2-7, formerly known as P. trivialis and P. reactans, elucidate its revised taxonomic classification, experimentally verify the gene predictions by transcriptome sequencing, describe its genetic biocontrol potential and contextualize it to other known Pseudomonas biocontrol agents. The P. brassicacearum 3Re2-7 genome comprises a circular chromosome with a size of 6,738,544 bp and a GC-content of 60.83%. 6267 genes were annotated, of which 6113 were shown to be transcribed in rich medium and/or in the presence of Rhizoctonia solani. Genome mining identified genes related to biocontrol traits such as secondary metabolite and siderophore biosynthesis, plant growth promotion, inorganic phosphate solubilization, biosynthesis of lipo- and exopolysaccharides, exoproteases, volatiles and detoxification. Core genome analysis revealed, that the 3Re2-7 genome exhibits a high collinearity with the representative genome for the species, P. brassicacearum subsp. brassicacearum NFM421. Comparative genomics allowed the identification of 105 specific genes and revealed gene clusters that might encode specialized biocontrol mechanisms of strain 3Re2-7. Moreover, we captured the transcriptome of P. brassicacearum 3Re2-7, confirming the transcription of the predicted biocontrol-related genes. The gene clusters coding for 2,4-diacetylphloroglucinol (phlABCDEFGH) and hydrogen cyanide (hcnABC) were shown to be highly transcribed. Further genes predicted to encode putative alginate production enzymes, a pyrroloquinoline quinone precursor peptide PqqA and a matrixin family metalloprotease were also found to be highly transcribed. With this study, we provide a basis to further characterize the mechanisms for biocontrol in Pseudomonas species, towards a sustainable and safe application of P. brassicacearum biocontrol agents.
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Affiliation(s)
- Johanna Nelkner
- Center for Biotechnology (CeBiTec), Bielefeld University, Genome Research of Industrial Microorganisms, Universitätsstraße 27, 33615 Bielefeld, Germany
| | - Gonzalo Torres Tejerizo
- Facultad de Ciencias Exactas, Departamento de Ciencias Biologicas, IBBM, Universidad Nacional de La Plata, Calle 115 y 47, 1900 La Plata, Argentina
| | - Julia Hassa
- Center for Biotechnology (CeBiTec), Bielefeld University, Genome Research of Industrial Microorganisms, Universitätsstraße 27, 33615 Bielefeld, Germany
| | - Timo Wentong Lin
- Center for Biotechnology (CeBiTec), Bielefeld University, Genome Research of Industrial Microorganisms, Universitätsstraße 27, 33615 Bielefeld, Germany
| | - Julian Witte
- Center for Biotechnology (CeBiTec), Bielefeld University, Genome Research of Industrial Microorganisms, Universitätsstraße 27, 33615 Bielefeld, Germany
| | - Bart Verwaaijen
- Center for Biotechnology (CeBiTec), Bielefeld University, Genome Research of Industrial Microorganisms, Universitätsstraße 27, 33615 Bielefeld, Germany
| | - Anika Winkler
- Center for Biotechnology (CeBiTec), Bielefeld University, Genome Research of Industrial Microorganisms, Universitätsstraße 27, 33615 Bielefeld, Germany
| | - Boyke Bunk
- Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Cathrin Spröer
- Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Jörg Overmann
- Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Rita Grosch
- Leibniz-Institute of Vegetable and Ornamental Crops (IGZ), Plant-Microbe Systems, Theodor-Echtermeyer-Weg 1, 14979 Großbeeren, Germany
| | - Alfred Pühler
- Center for Biotechnology (CeBiTec), Bielefeld University, Genome Research of Industrial Microorganisms, Universitätsstraße 27, 33615 Bielefeld, Germany
| | - And Andreas Schlüter
- Center for Biotechnology (CeBiTec), Bielefeld University, Genome Research of Industrial Microorganisms, Universitätsstraße 27, 33615 Bielefeld, Germany.
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Polano C, Martini M, Savian F, Moruzzi S, Ermacora P, Firrao G. Genome Sequence and Antifungal Activity of Two Niche-Sharing Pseudomonas protegens Related Strains Isolated from Hydroponics. MICROBIAL ECOLOGY 2019; 77:1025-1035. [PMID: 30088023 DOI: 10.1007/s00248-018-1238-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 07/23/2018] [Indexed: 06/08/2023]
Abstract
This work reports the comparison of the genome sequence and the ability to inhibit fungal growth of two Pseudomonas protegens related strains that were isolated from the same hydroponic culture of lamb's lettuce. The two strains were very similar in their core genome but one strain, Pf4, contained three gene clusters for the production of secondary metabolites, i.e., pyoluteorin (plt), pyrrolnitrin (prn), and rhizoxin (rzx), that were missing in the other strain, Pf11. The difference between the two strains was not due to simple insertion events, but to a relatively complex differentiation focused on the accessory genomes. In dual culture assays, both strains inhibited nearly all tested fungal strains, yet Pf4 exerted a significantly stronger fungal growth inhibition than Pf11. In addition to the differences in the secondary metabolite production associated genes abundance, the genome of Pf4 was more stable, smaller in size and with a lower number of transposons. The preservation of a dynamic equilibrium within natural populations of different strains comprised in the same species but differing in their secondary metabolite repertoire and in their genome stability may be functional to the adaptation to environmental changes.
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Affiliation(s)
- Cesare Polano
- Department of Agricultural, Food, Environmental and Animal Sciences (DI4A), University of Udine, Via delle Scienze 206, 33100, Udine, Italy
| | - Marta Martini
- Department of Agricultural, Food, Environmental and Animal Sciences (DI4A), University of Udine, Via delle Scienze 206, 33100, Udine, Italy
| | - Francesco Savian
- Department of Agricultural, Food, Environmental and Animal Sciences (DI4A), University of Udine, Via delle Scienze 206, 33100, Udine, Italy
| | - Serena Moruzzi
- Department of Agricultural, Food, Environmental and Animal Sciences (DI4A), University of Udine, Via delle Scienze 206, 33100, Udine, Italy
| | - Paolo Ermacora
- Department of Agricultural, Food, Environmental and Animal Sciences (DI4A), University of Udine, Via delle Scienze 206, 33100, Udine, Italy
| | - Giuseppe Firrao
- Department of Agricultural, Food, Environmental and Animal Sciences (DI4A), University of Udine, Via delle Scienze 206, 33100, Udine, Italy.
- National Institute of Biostructures and Biosystems, Viale delle Medaglie d'Oro 305, Rome, Italy.
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Pseudomonas aeruginosa Predominates as Multifaceted Rhizospheric Bacteria with Combined Abilities of P-solubilization and Biocontrol. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2019. [DOI: 10.22207/jpam.13.1.35] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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40
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Besset-Manzoni Y, Rieusset L, Joly P, Comte G, Prigent-Combaret C. Exploiting rhizosphere microbial cooperation for developing sustainable agriculture strategies. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:29953-29970. [PMID: 29313197 DOI: 10.1007/s11356-017-1152-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 12/26/2017] [Indexed: 05/23/2023]
Abstract
The rhizosphere hosts a considerable microbial community. Among that community, bacteria called plant growth-promoting rhizobacteria (PGPR) can promote plant growth and defense against diseases using diverse distinct plant-beneficial functions. Crop inoculation with PGPR could allow to reduce the use of pesticides and fertilizers in agrosystems. However, microbial crop protection and growth stimulation would be more efficient if cooperation between rhizosphere bacterial populations was taken into account when developing biocontrol agents and biostimulants. Rhizospheric bacteria live in multi-species biofilms formed all along the root surface or sometimes inside the plants (i.e., endophyte). PGPR cooperate with their host plants and also with other microbial populations inside biofilms. These interactions are mediated by a large diversity of microbial metabolites and physical signals that trigger cell-cell communication and appropriate responses. A better understanding of bacterial behavior and microbial cooperation in the rhizosphere could allow for a more successful use of bacteria in sustainable agriculture. This review presents an ecological view of microbial cooperation in agrosystems and lays the emphasis on the main microbial metabolites involved in microbial cooperation, plant health protection, and plant growth stimulation. Eco-friendly inoculant consortia that will foster microbe-microbe and microbe-plant cooperation can be developed to promote crop growth and restore biodiversity and functions lost in agrosystems.
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Affiliation(s)
- Yoann Besset-Manzoni
- UMR Ecologie Microbienne, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 43 bd du 11 Novembre 1918, F-69622, Villeurbanne cedex, France
- Biovitis, 15 400, Saint Etienne-de-Chomeil, France
| | - Laura Rieusset
- UMR Ecologie Microbienne, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 43 bd du 11 Novembre 1918, F-69622, Villeurbanne cedex, France
| | - Pierre Joly
- Biovitis, 15 400, Saint Etienne-de-Chomeil, France
| | - Gilles Comte
- UMR Ecologie Microbienne, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 43 bd du 11 Novembre 1918, F-69622, Villeurbanne cedex, France
| | - Claire Prigent-Combaret
- UMR Ecologie Microbienne, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 43 bd du 11 Novembre 1918, F-69622, Villeurbanne cedex, France.
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Tchagang CF, Xu R, Overy D, Blackwell B, Chabot D, Hubbard K, Doumbou CL, Bromfield ESP, Tambong JT. Diversity of bacteria associated with corn roots inoculated with Canadian woodland soils, and description of Pseudomonas aylmerense sp. nov. Heliyon 2018; 4:e00761. [PMID: 30186983 PMCID: PMC6120581 DOI: 10.1016/j.heliyon.2018.e00761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 08/24/2018] [Accepted: 08/24/2018] [Indexed: 11/15/2022] Open
Abstract
Bacteria associated with corn roots inoculated with soils collected from the Canadian woodlands were isolated and characterized. Genus-level identification based on 16S rRNA sequence analysis classified the 161 isolates in 19 genera. The majority (64%) of the isolates were affiliated with the genus Pseudomonas. Further analysis of the Pseudomonas isolates based on BLASTn and rpoD-rpoB-gyrB concatenated gene phylogeny revealed three unique clusters that could not be assigned to known species. This study reports the taxonomic description of one of the distinct lineages represented by two strains (S1E40T and S1E44) with P. lurida LMG 21995T, P. costantinii LMG 22119T, P. palleroniana LMG 23076T, P. simiae CCUG 50988T and P. extremorientalis LMG 19695T as the closest taxa. Both strains showed low ANIm (<90%) and genome-based DNA-DNA hybridization (<50%) values, which unequivocally delineated the new strains from the closest relatives. These findings were supported by multilocus sequence analysis (MLSA) and DNA fingerprinting. In addition, growth characteristics and biochemical tests revealed patterns that differed from the related species. Strains S1E40T and S1E44 are Gram-negative, aerobic, rod-shaped and motile by at least one flagellum; and grew optimally at 30 °C. The predominant polar lipid is phosphatidylethanolamine while the major respiratory quinone is ubiquinone-9. Based on phenotypic and genotypic data presented here, strains S1E40T and S1E44 represent a novel species for which the name Pseudomonas aylmerense sp. nov. is proposed. The type strain is S1E40T (= LMG 30784T = DOAB 703T = HAMI 3696T) with a G + C content of 61.6%.
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Affiliation(s)
- Caetanie F Tchagang
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada.,Institut des sciences de la santé et de la vie, Collège La Cité, 801 Aviation Parkway, Ottawa, Ontario, Canada
| | - Renlin Xu
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - David Overy
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - Barbara Blackwell
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - Denise Chabot
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - Keith Hubbard
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - Cyr Lézin Doumbou
- Institut des sciences de la santé et de la vie, Collège La Cité, 801 Aviation Parkway, Ottawa, Ontario, Canada
| | - Eden S P Bromfield
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - James T Tambong
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
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Roberts DC, Fleischer SJ, Sakamoto JM, Rasgon JL. Potential biological control of Erwinia tracheiphila by internal alimentary canal interactions in Acalymma vittatum with Pseudomonas fluorescens. J Appl Microbiol 2018; 125:1137-1146. [PMID: 29890026 DOI: 10.1111/jam.13950] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 05/01/2018] [Accepted: 05/19/2018] [Indexed: 11/27/2022]
Abstract
AIMS We aim to determine if Pseudomonas fluorescens is a viable biological control for Erwinia tracheiphila within the insect vector, Acalymma vittatum. METHODS AND RESULTS Pseudomonas fluorescens secreted fluorescein and inhibited growth of E. tracheiphila in disc diffusion assays. To determine if this antagonism was conserved within the insect vector, we performed in vivo assays by orally injecting beetles with bacterial treatments and fluorescent in situ hybridization to determine bacterial presence within the alimentary canal. CONCLUSIONS Pseudomonas fluorescens inhibited the growth of E. tracheiphila on a nutrient-limiting medium. In situ experiments demonstrated that P. fluorescens is maintained within the alimentary canal of the beetle for at least 4 days, and co-occurred with E. tracheiphila. When beetles were first presented with Pseudomonas and then challenged with E. tracheiphila, E. tracheiphila was not recovered via FISH after 4 days. These data suggest that P. fluorescens has potential as a biological control agent to limit E. tracheiphila within the insect vector. SIGNIFICANCE AND IMPACT OF THE STUDY This is a novel approach for controlling E. tracheiphila that has the potential to decrease reliance on insecticides, providing a safer environment for pollinators and growers.
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Affiliation(s)
- D C Roberts
- The Pennsylvania State University, University Park, PA, USA
| | - S J Fleischer
- The Pennsylvania State University, University Park, PA, USA
| | - J M Sakamoto
- The Pennsylvania State University, University Park, PA, USA
| | - J L Rasgon
- The Pennsylvania State University, University Park, PA, USA
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43
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Dignam BEA, O'Callaghan M, Condron LM, Kowalchuk GA, Van Nostrand JD, Zhou J, Wakelin SA. Effect of land use and soil organic matter quality on the structure and function of microbial communities in pastoral soils: Implications for disease suppression. PLoS One 2018; 13:e0196581. [PMID: 29734390 PMCID: PMC5937765 DOI: 10.1371/journal.pone.0196581] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 04/16/2018] [Indexed: 01/22/2023] Open
Abstract
Cropping soils vary in extent of natural suppression of soil-borne plant diseases. However, it is unknown whether similar variation occurs across pastoral agricultural systems. We examined soil microbial community properties known to be associated with disease suppression across 50 pastoral fields varying in management intensity. The composition and abundance of the disease-suppressive community were assessed from both taxonomic and functional perspectives. Pseudomonas bacteria were selected as a general taxonomic indicator of disease suppressive potential, while genes associated with the biosynthesis of a suite of secondary metabolites provided functional markers (GeoChip 5.0 microarray analysis). The composition of both the Pseudomonas communities and disease suppressive functional genes were responsive to land use. Underlying soil properties explained 37% of the variation in Pseudomonas community structure and up to 61% of the variation in the abundance of disease suppressive functional genes. Notably, measures of soil organic matter quality, C:P ratio, and aromaticity of the dissolved organic matter content (carbon recalcitrance), influenced both the taxonomic and functional disease suppressive potential of the pasture soils. Our results suggest that key components of the soil microbial community may be managed on-farm to enhance disease suppression and plant productivity.
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Affiliation(s)
- Bryony E A Dignam
- Bio-protection Research Centre, Lincoln University, Lincoln, Christchurch, New Zealand.,Soil Biology, Farm Systems & Environment, AgResearch Ltd, Lincoln, Christchurch, New Zealand
| | - Maureen O'Callaghan
- Bio-protection Research Centre, Lincoln University, Lincoln, Christchurch, New Zealand.,Soil Biology, Farm Systems & Environment, AgResearch Ltd, Lincoln, Christchurch, New Zealand
| | - Leo M Condron
- Bio-protection Research Centre, Lincoln University, Lincoln, Christchurch, New Zealand
| | - George A Kowalchuk
- Ecology and Biodiversity, Institute of Environmental Biology, Utrecht University, Utrecht, The Netherlands
| | - Joy D Van Nostrand
- Institute for Environmental Genomics, University of Oklahoma, Norman, Oklahoma, United States of America
| | - Jizhong Zhou
- Institute for Environmental Genomics, University of Oklahoma, Norman, Oklahoma, United States of America.,Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America.,State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China
| | - Steven A Wakelin
- Bio-protection Research Centre, Lincoln University, Lincoln, Christchurch, New Zealand.,Soil Biology, Farm Systems & Environment, AgResearch Ltd, Lincoln, Christchurch, New Zealand.,Scion Research Ltd, Christchurch, New Zealand
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44
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Etesami H, Beattie GA. Mining Halophytes for Plant Growth-Promoting Halotolerant Bacteria to Enhance the Salinity Tolerance of Non-halophytic Crops. Front Microbiol 2018; 9:148. [PMID: 29472908 PMCID: PMC5809494 DOI: 10.3389/fmicb.2018.00148] [Citation(s) in RCA: 139] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 01/23/2018] [Indexed: 11/20/2022] Open
Abstract
Salinity stress is one of the major abiotic stresses limiting crop production in arid and semi-arid regions. Interest is increasing in the application of PGPRs (plant growth promoting rhizobacteria) to ameliorate stresses such as salinity stress in crop production. The identification of salt-tolerant, or halophilic, PGPRs has the potential to promote saline soil-based agriculture. Halophytes are a useful reservoir of halotolerant bacteria with plant growth-promoting capabilities. Here, we review recent studies on the use of halophilic PGPRs to stimulate plant growth and increase the tolerance of non-halophytic crops to salinity. These studies illustrate that halophilic PGPRs from the rhizosphere of halophytic species can be effective bio-inoculants for promoting the production of non-halophytic species in saline soils. These studies support the viability of bioinoculation with halophilic PGPRs as a strategy for the sustainable enhancement of non-halophytic crop growth. The potential of this strategy is discussed within the context of ensuring sustainable food production for a world with an increasing population and continuing climate change. We also explore future research needs for using halotolerant PGPRs under salinity stress.
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Affiliation(s)
- Hassan Etesami
- Department of Soil Science, Faculty of Agricultural Engineering & Technology, University of Tehran, Tehran, Iran
| | - Gwyn A. Beattie
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, United States
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45
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Vacheron J, Desbrosses G, Renoud S, Padilla R, Walker V, Muller D, Prigent-Combaret C. Differential Contribution of Plant-Beneficial Functions from Pseudomonas kilonensis F113 to Root System Architecture Alterations in Arabidopsis thaliana and Zea mays. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2018; 31:212-223. [PMID: 28971723 DOI: 10.1094/mpmi-07-17-0185-r] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Fluorescent pseudomonads are playing key roles in plant-bacteria symbiotic interactions due to the multiple plant-beneficial functions (PBFs) they are harboring. The relative contributions of PBFs to plant-stimulatory effects of the well-known plant growth-promoting rhizobacteria Pseudomonas kilonensis F113 (formerly P. fluorescens F113) were investigated using a genetic approach. To this end, several deletion mutants were constructed, simple mutants ΔphlD (impaired in the biosynthesis of 2,4-diacetylphloroglucinol [DAPG]), ΔacdS (deficient in 1-aminocyclopropane-1-carboxylate deaminase activity), Δgcd (glucose dehydrogenase deficient, impaired in phosphate solubilization), and ΔnirS (nitrite reductase deficient), and a quadruple mutant (deficient in the four PBFs mentioned above). Every PBF activity was quantified in the wild-type strain and the five deletion mutants. This approach revealed few functional interactions between PBFs in vitro. In particular, biosynthesis of glucose dehydrogenase severely reduced the production of DAPG. Contrariwise, the DAPG production impacted positively, but to a lesser extent, phosphate solubilization. Inoculation of the F113 wild-type strain on Arabidopsis thaliana Col-0 and maize seedlings modified the root architecture of both plants. Mutant strain inoculations revealed that the relative contribution of each PBF differed according to the measured plant traits and that F113 plant-stimulatory effects did not correspond to the sum of each PBF relative contribution. Indeed, two PBF genes (ΔacdS and ΔnirS) had a significant impact on root-system architecture from both model plants, in in vitro and in vivo conditions. The current work underscored that few F113 PBFs seem to interact between each other in the free-living bacterial cells, whereas they control in concert Arabidopsis thaliana and maize growth and development.
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Affiliation(s)
- Jordan Vacheron
- 1 UMR Ecologie Microbienne, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 43 bd du 11 Novembre, F-69622 Villeurbanne, France; and
| | - Guilhem Desbrosses
- 2 CNRS, INRA, UMR5004, Biochimie & Physiologie Moléculaire des Plantes, Montpellier, France
| | - Sébastien Renoud
- 1 UMR Ecologie Microbienne, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 43 bd du 11 Novembre, F-69622 Villeurbanne, France; and
| | - Rosa Padilla
- 1 UMR Ecologie Microbienne, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 43 bd du 11 Novembre, F-69622 Villeurbanne, France; and
| | - Vincent Walker
- 1 UMR Ecologie Microbienne, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 43 bd du 11 Novembre, F-69622 Villeurbanne, France; and
| | - Daniel Muller
- 1 UMR Ecologie Microbienne, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 43 bd du 11 Novembre, F-69622 Villeurbanne, France; and
| | - Claire Prigent-Combaret
- 1 UMR Ecologie Microbienne, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 43 bd du 11 Novembre, F-69622 Villeurbanne, France; and
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46
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47
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Martínez-Raudales I, De La Cruz-Rodríguez Y, Alvarado-Gutiérrez A, Vega-Arreguín J, Fraire-Mayorga A, Alvarado-Rodríguez M, Balderas-Hernández V, Fraire-Velázquez S. Draft genome sequence of Bacillus velezensis 2A-2B strain: a rhizospheric inhabitant of Sporobolus airoides (Torr.) Torr ., with antifungal activity against root rot causing phytopathogens. Stand Genomic Sci 2017; 12:73. [PMID: 29225729 PMCID: PMC5717847 DOI: 10.1186/s40793-017-0289-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 11/24/2017] [Indexed: 12/13/2022] Open
Abstract
A Bacillus velezensis strain from the rhizosphere of Sporobolus airoides (Torr.) Torr., a grass in central-north México, was isolated during a biocontrol of phytopathogens scrutiny study. The 2A-2B strain exhibited at least 60% of growth inhibition of virulent isolates of phytopathogens causing root rot. These phytopathogens include Phytophthora capsici, Fusarium solani, Fusarium oxysporum and Rhizoctonia solani. Furthermore, the 2A-2B strain is an indolacetic acid producer, and a plant inducer of PR1, which is an induced systemic resistance related gene in chili pepper plantlets. Whole genome sequencing was performed to generate a draft genome assembly of 3.953 MB with 46.36% of GC content, and a N50 of 294,737. The genome contains 3713 protein coding genes and 89 RNA genes. Moreover, comparative genome analysis revealed that the 2A-2B strain had the greatest identity (98.4%) with Bacillus velezensis.
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Affiliation(s)
- Inés Martínez-Raudales
- Laboratorio Biología Integrativa de Plantas y Microorganismos, Unidad Académica de Ciencias Biológicas, Universidad Autónoma de Zacatecas, Av. Preparatoria s/n, Col. Agronómica, Zac. CP, -98067 Zacatecas, Mexico
| | - Yumiko De La Cruz-Rodríguez
- Laboratorio Biología Integrativa de Plantas y Microorganismos, Unidad Académica de Ciencias Biológicas, Universidad Autónoma de Zacatecas, Av. Preparatoria s/n, Col. Agronómica, Zac. CP, -98067 Zacatecas, Mexico
| | - Alejandro Alvarado-Gutiérrez
- Laboratorio Biología Integrativa de Plantas y Microorganismos, Unidad Académica de Ciencias Biológicas, Universidad Autónoma de Zacatecas, Av. Preparatoria s/n, Col. Agronómica, Zac. CP, -98067 Zacatecas, Mexico
| | | | - Ahuitz Fraire-Mayorga
- Laboratorio Biología Integrativa de Plantas y Microorganismos, Unidad Académica de Ciencias Biológicas, Universidad Autónoma de Zacatecas, Av. Preparatoria s/n, Col. Agronómica, Zac. CP, -98067 Zacatecas, Mexico
| | - Miguel Alvarado-Rodríguez
- Laboratorio Biología Integrativa de Plantas y Microorganismos, Unidad Académica de Ciencias Biológicas, Universidad Autónoma de Zacatecas, Av. Preparatoria s/n, Col. Agronómica, Zac. CP, -98067 Zacatecas, Mexico
| | - Victor Balderas-Hernández
- Laboratorio Biología Integrativa de Plantas y Microorganismos, Unidad Académica de Ciencias Biológicas, Universidad Autónoma de Zacatecas, Av. Preparatoria s/n, Col. Agronómica, Zac. CP, -98067 Zacatecas, Mexico
| | - Saúl Fraire-Velázquez
- Laboratorio Biología Integrativa de Plantas y Microorganismos, Unidad Académica de Ciencias Biológicas, Universidad Autónoma de Zacatecas, Av. Preparatoria s/n, Col. Agronómica, Zac. CP, -98067 Zacatecas, Mexico
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48
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Haney CH, Wiesmann CL, Shapiro LR, Melnyk RA, O'Sullivan LR, Khorasani S, Xiao L, Han J, Bush J, Carrillo J, Pierce NE, Ausubel FM. Rhizosphere-associated Pseudomonas induce systemic resistance to herbivores at the cost of susceptibility to bacterial pathogens. Mol Ecol 2017; 27:1833-1847. [PMID: 29087012 DOI: 10.1111/mec.14400] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 10/18/2017] [Accepted: 10/19/2017] [Indexed: 01/02/2023]
Abstract
Plant-associated soil microbes are important mediators of plant defence responses to diverse above-ground pathogen and insect challengers. For example, closely related strains of beneficial rhizosphere Pseudomonas spp. can induce systemic resistance (ISR), systemic susceptibility (ISS) or neither against the bacterial foliar pathogen Pseudomonas syringae pv. tomato DC3000 (Pto DC3000). Using a model system composed of root-associated Pseudomonas spp. strains, the foliar pathogen Pto DC3000 and the herbivore Trichoplusia ni (cabbage looper), we found that rhizosphere-associated Pseudomonas spp. that induce either ISS and ISR against Pto DC3000 all increased resistance to herbivory by T. ni. We found that resistance to T. ni and resistance to Pto DC3000 are quantitative metrics of the jasmonic acid (JA)/salicylic acid (SA) trade-off and distinct strains of rhizosphere-associated Pseudomonas spp. have distinct effects on the JA/SA trade-off. Using genetic analysis and transcriptional profiling, we provide evidence that treatment of Arabidopsis with Pseudomonas sp. CH267, which induces ISS against bacterial pathogens, tips the JA/SA trade-off towards JA-dependent defences against herbivores at the cost of a subset of SA-mediated defences against bacterial pathogens. In contrast, treatment of Arabidopsis with the ISR strain Pseudomonas sp. WCS417 disrupts JA/SA antagonism and simultaneously primes plants for both JA- and SA-mediated defences. Our findings show that ISS against the bacterial foliar pathogens triggered by Pseudomonas sp. CH267, which is a seemingly deleterious phenotype, may in fact be an adaptive consequence of increased resistance to herbivory. Our work shows that pleiotropic effects of microbiome modulation of plant defences are important to consider when using microbes to modify plant traits in agriculture.
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Affiliation(s)
- Cara H Haney
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada.,Michael Smith Laboratories, The University of British Columbia, Vancouver, BC, Canada
| | - Christina L Wiesmann
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada
| | - Lori R Shapiro
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.,Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA.,Department of Applied Ecology, North Carolina State University, Raleigh, NC, USA
| | - Ryan A Melnyk
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada
| | - Lucy R O'Sullivan
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
| | - Sophie Khorasani
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
| | - Li Xiao
- Land and Food Systems, The University of British Columbia, Vancouver, BC, Canada.,Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Jiatong Han
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada
| | - Jenifer Bush
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
| | - Juli Carrillo
- Land and Food Systems, The University of British Columbia, Vancouver, BC, Canada
| | - Naomi E Pierce
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Frederick M Ausubel
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA.,Department of Genetics, Harvard Medical School, Boston, MA, USA
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49
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Saleh MY, Sarhan MS, Mourad EF, Hamza MA, Abbas MT, Othman AA, Youssef HH, Morsi AT, Youssef GH, El-Tahan M, Amer WA, Fayez M, Ruppel S, Hegazi NA. A novel plant-based-sea water culture media for in vitro cultivation and in situ recovery of the halophyte microbiome. J Adv Res 2017; 8:577-590. [PMID: 28794903 PMCID: PMC5540709 DOI: 10.1016/j.jare.2017.06.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 06/24/2017] [Accepted: 06/26/2017] [Indexed: 11/29/2022] Open
Abstract
The plant-based-sea water culture medium is introduced to in vitro cultivation and in situ recovery of the microbiome of halophytes. The ice plant (Mesembryanthemum crystallinum) was used, in the form of juice and/or dehydrated plant powder packed in teabags, to supplement the natural sea water. The resulting culture medium enjoys the combinations of plant materials as rich source of nutrients and sea water exercising the required salt stress. As such without any supplements, the culture medium was sufficient and efficient to support very good in vitro growth of halotolerant bacteria. It was also capable to recover their in situ culturable populations in the phyllosphere, ecto-rhizosphere and endo-rhizosphere of halophytes prevailing in Lake Mariout, Egypt. When related to the total bacterial numbers measured for Suaeda pruinosa roots by quantitative-PCR, the proposed culture medium increased culturability (15.3-19.5%) compared to the conventional chemically-synthetic culture medium supplemented with (11.2%) or without (3.8%) NaCl. Based on 16S rRNA gene sequencing, representative isolates of halotolerant bacteria prevailed on such culture medium were closely related to Bacillus spp., Halomonas spp., and Kocuria spp. Seed germination tests on 25-50% sea water agar indicated positive interaction of such bacterial isolates with the germination and seedlings' growth of barley seeds.
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Affiliation(s)
- Mohamed Y. Saleh
- Department of Microbiology, Faculty of Agriculture, Cairo University, 12613 Giza, Egypt
| | - Mohamed S. Sarhan
- Department of Microbiology, Faculty of Agriculture, Cairo University, 12613 Giza, Egypt
| | - Elhussein F. Mourad
- Department of Microbiology, Faculty of Agriculture, Cairo University, 12613 Giza, Egypt
| | - Mervat A. Hamza
- Department of Microbiology, Faculty of Agriculture, Cairo University, 12613 Giza, Egypt
| | - Mohamed T. Abbas
- Microbiology Department, Faculty of Agriculture and Natural Resources, Aswan University, P.O. Box 81528, Aswan, Egypt
| | - Amal A. Othman
- Hydrobiology Laboratory, Inland Water and Lake Division, National Institute of Oceanography and Fisheries (NIOF), 11516 Cairo, Egypt
| | - Hanan H. Youssef
- Department of Microbiology, Faculty of Agriculture, Cairo University, 12613 Giza, Egypt
| | - Ahmed T. Morsi
- Department of Microbiology, Faculty of Agriculture, Cairo University, 12613 Giza, Egypt
| | - Gehan H. Youssef
- Soils, Water and Environment Research Institute, Agricultural Research Center, 12112 Giza, Egypt
| | - Mahmoud El-Tahan
- Institute of Feed Research, Agricultural Research Center, 12112 Giza, Egypt
| | - Wafaa A. Amer
- Department of Botany and Microbiology, Faculty of Science, Cairo University, 12613 Giza, Egypt
| | - Mohamed Fayez
- Department of Microbiology, Faculty of Agriculture, Cairo University, 12613 Giza, Egypt
| | - Silke Ruppel
- Leibniz Institute of Vegetable and Ornamental Crops (IGZ), 14979 Grossbeeren, Germany
| | - Nabil A. Hegazi
- Department of Microbiology, Faculty of Agriculture, Cairo University, 12613 Giza, Egypt
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50
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Mechanisms of action of plant growth promoting bacteria. World J Microbiol Biotechnol 2017; 33:197. [PMID: 28986676 PMCID: PMC5686270 DOI: 10.1007/s11274-017-2364-9] [Citation(s) in RCA: 354] [Impact Index Per Article: 50.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 10/04/2017] [Indexed: 01/01/2023]
Abstract
The idea of eliminating the use of fertilizers which are sometimes environmentally unsafe is slowly becoming a reality because of the emergence of microorganisms that can serve the same purpose or even do better. Depletion of soil nutrients through leaching into the waterways and causing contamination are some of the negative effects of these chemical fertilizers that prompted the need for suitable alternatives. This brings us to the idea of using microbes that can be developed for use as biological fertilizers (biofertilizers). They are environmentally friendly as they are natural living organisms. They increase crop yield and production and, in addition, in developing countries, they are less expensive compared to chemical fertilizers. These biofertilizers are typically called plant growth-promoting bacteria (PGPB). In addition to PGPB, some fungi have also been demonstrated to promote plant growth. Apart from improving crop yields, some biofertilizers also control various plant pathogens. The objective of worldwide sustainable agriculture is much more likely to be achieved through the widespread use of biofertilizers rather than chemically synthesized fertilizers. However, to realize this objective it is essential that the many mechanisms employed by PGPB first be thoroughly understood thereby allowing workers to fully harness the potentials of these microbes. The present state of our knowledge regarding the fundamental mechanisms employed by PGPB is discussed herein.
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