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Mohaimin AZ, Krishnamoorthy S, Shivanand P. A critical review on bioaerosols-dispersal of crop pathogenic microorganisms and their impact on crop yield. Braz J Microbiol 2024; 55:587-628. [PMID: 38001398 PMCID: PMC10920616 DOI: 10.1007/s42770-023-01179-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 11/07/2023] [Indexed: 11/26/2023] Open
Abstract
Bioaerosols are potential sources of pathogenic microorganisms that can cause devastating outbreaks of global crop diseases. Various microorganisms, insects and viroids are known to cause severe crop diseases impeding global agro-economy. Such losses threaten global food security, as it is estimated that almost 821 million people are underfed due to global crisis in food production. It is estimated that global population would reach 10 billion by 2050. Hence, it is imperative to substantially increase global food production to about 60% more than the existing levels. To meet the increasing demand, it is essential to control crop diseases and increase yield. Better understanding of the dispersive nature of bioaerosols, seasonal variations, regional diversity and load would enable in formulating improved strategies to control disease severity, onset and spread. Further, insights on regional and global bioaerosol composition and dissemination would help in predicting and preventing endemic and epidemic outbreaks of crop diseases. Advanced knowledge of the factors influencing disease onset and progress, mechanism of pathogen attachment and penetration, dispersal of pathogens, life cycle and the mode of infection, aid the development and implementation of species-specific and region-specific preventive strategies to control crop diseases. Intriguingly, development of R gene-mediated resistant varieties has shown promising results in controlling crop diseases. Forthcoming studies on the development of an appropriately stacked R gene with a wide range of resistance to crop diseases would enable proper management and yield. The article reviews various aspects of pathogenic bioaerosols, pathogen invasion and infestation, crop diseases and yield.
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Affiliation(s)
- Abdul Zul'Adly Mohaimin
- Environmental and Life Sciences Programme, Faculty of Science, Universiti Brunei Darussalam, Jalan Tungku Link, Bandar Seri Begawan, BE1410, Brunei Darussalam
| | - Sarayu Krishnamoorthy
- Environmental and Life Sciences Programme, Faculty of Science, Universiti Brunei Darussalam, Jalan Tungku Link, Bandar Seri Begawan, BE1410, Brunei Darussalam
| | - Pooja Shivanand
- Environmental and Life Sciences Programme, Faculty of Science, Universiti Brunei Darussalam, Jalan Tungku Link, Bandar Seri Begawan, BE1410, Brunei Darussalam.
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Zhou L, Höfte M, Hennessy RC. Does regulation hold the key to optimizing lipopeptide production in Pseudomonas for biotechnology? Front Bioeng Biotechnol 2024; 12:1363183. [PMID: 38476965 PMCID: PMC10928948 DOI: 10.3389/fbioe.2024.1363183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 02/12/2024] [Indexed: 03/14/2024] Open
Abstract
Lipopeptides (LPs) produced by Pseudomonas spp. are specialized metabolites with diverse structures and functions, including powerful biosurfactant and antimicrobial properties. Despite their enormous potential in environmental and industrial biotechnology, low yield and high production cost limit their practical use. While genome mining and functional genomics have identified a multitude of LP biosynthetic gene clusters, the regulatory mechanisms underlying their biosynthesis remain poorly understood. We propose that regulation holds the key to unlocking LP production in Pseudomonas for biotechnology. In this review, we summarize the structure and function of Pseudomonas-derived LPs and describe the molecular basis for their biosynthesis and regulation. We examine the global and specific regulator-driven mechanisms controlling LP synthesis including the influence of environmental signals. Understanding LP regulation is key to modulating production of these valuable compounds, both quantitatively and qualitatively, for industrial and environmental biotechnology.
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Affiliation(s)
- Lu Zhou
- Laboratory of Phytopathology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Monica Höfte
- Laboratory of Phytopathology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Rosanna C. Hennessy
- Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
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Huang S, Zha X, Fu G. Affecting Factors of Plant Phyllosphere Microbial Community and Their Responses to Climatic Warming-A Review. PLANTS (BASEL, SWITZERLAND) 2023; 12:2891. [PMID: 37631103 PMCID: PMC10458011 DOI: 10.3390/plants12162891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 08/02/2023] [Accepted: 08/06/2023] [Indexed: 08/27/2023]
Abstract
Phyllosphere microorganisms are not only an important part of plants, but also an important part of microorganisms. In this review, the function of phyllosphere microorganisms, the assembly mechanism of phyllosphere microorganisms, the driving factors of phyllosphere microbial community structure, and the effects of climate warming on phyllosphere microbial community structure were reviewed. Generally, phyllosphere microorganisms have a variety of functions (e.g., fixing nitrogen, promoting plant growth). Although selection and dispersal processes together regulate the assembly of phyllospheric microbial communities, which one of the ecological processes is dominant and how external disturbances alter the relative contributions of each ecological process remains controversial. Abiotic factors (e.g., climatic conditions, geographical location and physical and chemical properties of soil) and biological factors (e.g., phyllosphere morphological structure, physiological and biochemical characteristics, and plant species and varieties) can affect phyllosphere microbial community structure. However, the predominant factors affecting phyllosphere microbial community structure are controversial. Moreover, how climate warming affects the phyllosphere microbial community structure and its driving mechanism have not been fully resolved, and further relevant studies are needed.
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Affiliation(s)
- Shaolin Huang
- Lhasa Plateau Ecosystem Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China;
| | - Xinjie Zha
- Xi’an University of Finance and Economics, Xi’an 710100, China;
| | - Gang Fu
- Lhasa Plateau Ecosystem Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China;
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Liu J, Zhang W, Liu Y, Zhu W, Yuan Z, Su X, Ding C. Differences in phyllosphere microbiomes among different Populus spp. in the same habitat. FRONTIERS IN PLANT SCIENCE 2023; 14:1143878. [PMID: 37063209 PMCID: PMC10098339 DOI: 10.3389/fpls.2023.1143878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 03/20/2023] [Indexed: 06/19/2023]
Abstract
INTRODUCTION The above-ground parts of terrestrial plants are collectively known as the phyllosphere. The surface of the leaf blade is a unique and extensive habitat for microbial communities. Phyllosphere bacteria are the second most closely associated microbial group with plants after fungi and viruses, and are the most abundant, occupying a dominant position in the phyllosphere microbial community. Host species are a major factor influencing the community diversity and structure of phyllosphere microorganisms. METHODS In this study, six Populus spp. were selected for study under the same site conditions and their phyllosphere bacterial community DNA fragments were paired-end sequenced using 16S ribosomal RNA (rRNA) gene amplicon sequencing. Based on the distribution of the amplicon sequence variants (ASVs), we assessed the alpha-diversity level of each sample and further measured the differences in species abundance composition among the samples, and predicted the metabolic function of the community based on the gene sequencing results. RESULTS The results revealed that different Populus spp. under the same stand conditions resulted in different phyllosphere bacterial communities. The bacterial community structure was mainly affected by the carbon and soluble sugar content of the leaves, and the leaf nitrogen, phosphorus and carbon/nitrogen were the main factors affecting the relative abundance of phyllosphere bacteria. DISCUSSION Previous studies have shown that a large proportion of the variation in the composition of phyllosphere microbial communities was explained by the hosts themselves. In contrast, leaf-borne nutrients were an available resource for bacteria living on the leaf surface, thus influencing the community structure of phyllosphere bacteria. These were similar to the conclusions obtained in this study. This study provides theoretical support for the study of the composition and structure of phyllosphere bacterial communities in woody plants and the factors influencing them.
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Affiliation(s)
- Jiaying Liu
- College of Forestry, Shenyang Agriculture University, Shenyang, China
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Weixi Zhang
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
- Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Yuting Liu
- College of Forestry, Shenyang Agriculture University, Shenyang, China
| | - Wenxu Zhu
- College of Forestry, Shenyang Agriculture University, Shenyang, China
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
- Research Station of Liaohe-River Plain Forest Ecosystem, Chinese Forest Ecosystem Research Network (CFERN), College of Forestry, Shenyang Agricultural University, Tieling, China
| | - Zhengsai Yuan
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
- Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Xiaohua Su
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
- Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Changjun Ding
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
- Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
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Orozco-Mosqueda MDC, Kumar A, Fadiji AE, Babalola OO, Puopolo G, Santoyo G. Agroecological Management of the Grey Mould Fungus Botrytis cinerea by Plant Growth-Promoting Bacteria. PLANTS (BASEL, SWITZERLAND) 2023; 12:637. [PMID: 36771719 PMCID: PMC9919678 DOI: 10.3390/plants12030637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Revised: 01/21/2023] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Botrytis cinerea is the causal agent of grey mould and one of the most important plant pathogens in the world because of the damage it causes to fruits and vegetables. Although the application of botrycides is one of the most common plant protection strategies used in the world, the application of plant-beneficial bacteria might replace botrycides facilitating agroecological production practices. Based on this, we reviewed the different stages of B. cinerea infection in plants and the biocontrol mechanisms exerted by plant-beneficial bacteria, including the well-known plant growth-promoting bacteria (PGPB). Some PGPB mechanisms to control grey mould disease include antibiosis, space occupation, nutrient uptake, ethylene modulation, and the induction of plant defence mechanisms. In addition, recent studies on the action of anti-Botrytis compounds produced by PGPB and how they damage the conidial and mycelial structures of the pathogen are reviewed. Likewise, the advantages of individual inoculations of PGPB versus those that require the joint action of antagonist agents (microbial consortia) are discussed. Finally, it should be emphasised that PGPB are an excellent option to prevent grey mould in different crops and their use should be expanded for environmentally friendly agricultural practices.
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Affiliation(s)
| | - Ajay Kumar
- Centre of Advanced study in Botany, Banaras Hindu University, Varanasi 221005, India
| | - Ayomide Emmanuel Fadiji
- Food Security and Safety Focus Area, Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa
| | - Olubukola Oluranti Babalola
- Food Security and Safety Focus Area, Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa
| | - Gerardo Puopolo
- Center Agriculture Food Environment (C3A), University of Trento, Via Edmund Mach 1, 38098 San Michele all’Adige, Italy
| | - Gustavo Santoyo
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia 58030, Mich, Mexico
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Zhang Y, Li X, Lu L, Huang F, Liu H, Zhang Y, Yang L, Usman M, Li S. Urbanization Reduces Phyllosphere Microbial Network Complexity and Species Richness of Camphor Trees. Microorganisms 2023; 11:microorganisms11020233. [PMID: 36838198 PMCID: PMC9966171 DOI: 10.3390/microorganisms11020233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 12/31/2022] [Accepted: 01/04/2023] [Indexed: 01/18/2023] Open
Abstract
Studies on microbial communities associated with foliage in natural ecosystems have grown in number in recent years yet have rarely focused on urban ecosystems. With urbanization, phyllosphere microorganisms in the urban environment have come under pressures from increasing human activities. To explore the effects of urbanization on the phyllosphere microbial communities of urban ecosystems, we investigated the phyllosphere microbial structure and the diversity of camphor trees in eight parks along a suburban-to-urban gradient. The results showed that the number of ASVs (amplicon sequence variants), unique on the phyllosphere microbial communities of three different urbanization gradients, was 4.54 to 17.99 times higher than that of the shared ASVs. Specific microbial biomarkers were also found for leaf samples from each urbanization gradient. Moreover, significant differences (R2 = 0.133, p = 0.005) were observed in the phyllosphere microbial structure among the three urbanization gradients. Alpha diversity and co-occurrence patterns of bacterial communities showed that urbanization can strongly reduce the complexity and species richness of the phyllosphere microbial network of camphor trees. Correlation analysis with environmental factors showed that leaf total carbon (C), nitrogen (N), and sulfur (S), as well as leaf C/N, soil pH, and artificial light intensity at night (ALIAN) were the important drivers in determining the divergence of phyllosphere microbial communities across the urbanization gradient. Together, we found that urbanization can affect the composition of the phyllosphere bacterial community of camphor trees, and that the interplay between human activities and plant microbial communities may contribute to shaping the urban microbiome.
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Affiliation(s)
- Yifang Zhang
- College of Environmental Science and Engineering, China West Normal University, Nanchong 637009, China
- Key Laboratory of Urban Environment and Health, Ningbo Observation and Research Station, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xiaomin Li
- Key Laboratory of Urban Environment and Health, Ningbo Observation and Research Station, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Lu Lu
- College of Environmental Science and Engineering, China West Normal University, Nanchong 637009, China
- Correspondence: (L.L.); (S.L.)
| | - Fuyi Huang
- Key Laboratory of Urban Environment and Health, Ningbo Observation and Research Station, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Hao Liu
- Department of Health and Environmental Sciences, Xi’an Jiaotong-Liverpool University, 111 Ren’ai Road, Suzhou 215123, China
| | - Yu Zhang
- State Key Lab of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Luhua Yang
- Key Laboratory of Urban Environment and Health, Ningbo Observation and Research Station, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Muhammad Usman
- PEIE Research Chair for the Development of Industrial Estates and Free Zones, Center for Environmental Studies and Research, Sultan Qaboos University, Al-Khoud, Muscat 123, Oman
| | - Shun Li
- Key Laboratory of Urban Environment and Health, Ningbo Observation and Research Station, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- Correspondence: (L.L.); (S.L.)
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Phylloplane Biodiversity and Activity in the City at Different Distances from the Traffic Pollution Source. PLANTS 2022; 11:plants11030402. [PMID: 35161383 PMCID: PMC8839900 DOI: 10.3390/plants11030402] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/24/2022] [Accepted: 01/27/2022] [Indexed: 11/17/2022]
Abstract
The phylloplane is an integrated part of green infrastructure which interacts with plant health. Taxonomic characterization of the phylloplane with the aim to link it to ecosystem functioning under anthropogenic pressure is not sufficient because only active microorganisms drive biochemical processes. Activity of the phylloplane remains largely overlooked. We aimed to study the interactions among the biological characteristics of the phylloplane: taxonomic diversity, functional diversity and activity, and the pollution grade. Leaves of Betula pendula were sampled in Moscow at increasing distances from the road. For determination of phylloplane activity and functional diversity, a MicroResp tool was utilized. Taxonomic diversity of the phylloplane was assessed with a combination of microorganism cultivation and molecular techniques. Increase of anthropogenic load resulted in higher microbial respiration and lower DNA amount, which could be viewed as relative inefficiency of phylloplane functioning in comparison to less contaminated areas. Taxonomic diversity declined with road vicinity, similar to the functional diversity pattern. The content of Zn in leaf dust better explained the variation in phylloplane activity and the amount of DNA. Functional diversity was linked to variation in nutrient content. The fraction of pathogenic fungi of the phylloplane was not correlated with any of the studied elements, while it was significantly high at the roadsides. The bacterial classes Gammaproteobacteria and Cytophagia, as well as the Dothideomycetes class of fungi, are exposed to the maximal effect of distance from the highway. This study demonstrated the sensitivity of the phylloplane to road vicinity, which combines the effects of contaminants (mainly Zn according to this study) and potential stressful air microclimatic conditions (e.g., low relative air humidity, high temperature, and UV level). Microbial activity and taxonomic diversity of the phylloplane could be considered as an additional tool for bioindication.
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Chaudhry V, Runge P, Sengupta P, Doehlemann G, Parker JE, Kemen E. Shaping the leaf microbiota: plant-microbe-microbe interactions. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:36-56. [PMID: 32910810 PMCID: PMC8210630 DOI: 10.1093/jxb/eraa417] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 09/07/2020] [Indexed: 05/28/2023]
Abstract
The aerial portion of a plant, namely the leaf, is inhabited by pathogenic and non-pathogenic microbes. The leaf's physical and chemical properties, combined with fluctuating and often challenging environmental factors, create surfaces that require a high degree of adaptation for microbial colonization. As a consequence, specific interactive processes have evolved to establish a plant leaf niche. Little is known about the impact of the host immune system on phyllosphere colonization by non-pathogenic microbes. These organisms can trigger plant basal defenses and benefit the host by priming for enhanced resistance to pathogens. In most disease resistance responses, microbial signals are recognized by extra- or intracellular receptors. The interactions tend to be species specific and it is unclear how they shape leaf microbial communities. In natural habitats, microbe-microbe interactions are also important for shaping leaf communities. To protect resources, plant colonizers have developed direct antagonistic or host manipulation strategies to fight competitors. Phyllosphere-colonizing microbes respond to abiotic and biotic fluctuations and are therefore an important resource for adaptive and protective traits. Understanding the complex regulatory host-microbe-microbe networks is needed to transfer current knowledge to biotechnological applications such as plant-protective probiotics.
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Affiliation(s)
- Vasvi Chaudhry
- Department of Microbial Interactions, IMIT/ZMBP, University of
Tübingen, Tübingen, Germany
| | - Paul Runge
- Department of Microbial Interactions, IMIT/ZMBP, University of
Tübingen, Tübingen, Germany
- Max Planck Institute for Plant Breeding Research, Köln, Germany
| | - Priyamedha Sengupta
- Institute for Plant Sciences and Cluster of Excellence on Plant Sciences
(CEPLAS), University of Cologne, Center for Molecular Biosciences, Cologne,
Germany
| | - Gunther Doehlemann
- Institute for Plant Sciences and Cluster of Excellence on Plant Sciences
(CEPLAS), University of Cologne, Center for Molecular Biosciences, Cologne,
Germany
| | - Jane E Parker
- Max Planck Institute for Plant Breeding Research, Köln, Germany
- Institute for Plant Sciences and Cluster of Excellence on Plant Sciences
(CEPLAS), University of Cologne, Center for Molecular Biosciences, Cologne,
Germany
| | - Eric Kemen
- Department of Microbial Interactions, IMIT/ZMBP, University of
Tübingen, Tübingen, Germany
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Raio A, Brilli F, Baraldi R, Neri L, Puopolo G. Impact of spontaneous mutations on physiological traits and biocontrol activity of Pseudomonas chlororaphis M71. Microbiol Res 2020; 239:126517. [PMID: 32535393 DOI: 10.1016/j.micres.2020.126517] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 05/06/2020] [Accepted: 05/13/2020] [Indexed: 10/24/2022]
Abstract
Three morphological mutants (M71a, M71b, M71c) of the antagonist Pseudomonas chlororaphis M71, naturally arose during a biocontrol trial against the phytopathogenic fungus Fusarium oxysporum f.sp. radicis-lycopersisci. In this study, the three mutants were investigated to elucidate their role in the biocontrol of plant pathogens. M71a and M71b phenotypes were generated by a mutation in the two-component system GacS/GacA. The mutation determined an increase in siderophore production and an impaired ability to release proteases, to swarm, to produce phenazine and AHLs and to colonize tomato roots. In vitro antagonistic activity against different plant pathogens was partially reduced in M71a, while M71b resulted effective only against Pythium ultimum. Biocontrol efficacy against Fusarium oxysporum f.sp. radicis-lycopersisci, was partially reduced in M71a and completely lost in M71b. M71c phenotype was impaired in swarming motility, did not produce biofilms and its antagonistic activity was similar to the parental M71 strain. M71c showed an enhanced ability to colonize tomato roots, on which its progeny in part reverted to the M71 parental phenotype. Volatile organic compounds (VOCs) emitted by all four strains, inhibited the growth of Clavibacter michiganensis subsp. michiganensis and Seiridium cardinale in vitro. Real-time screening of VOCs by PTR-MS combined with GC-MS analysis, showed that methanethiol was the main component of the blend produced by all four M71 strains. However, the emissions of hydrogen cyanide, dimethyl disulfide, 1,3-butadiene and acetone were significantly affected by the three different mutations. These findings highlight that the simultaneous presence of different M71 phenotypes may improve, through the integration of different mechanisms, the ecological fitness and biocontrol efficacy of P. chlororaphis M71.
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Affiliation(s)
- Aida Raio
- Institute for Sustainable Plant Protection, National Research Council, Via Madonna del Piano 10, 50019, Sesto Fiorentino, FI, Italy.
| | - Federico Brilli
- Institute for Sustainable Plant Protection, National Research Council, Via Madonna del Piano 10, 50019, Sesto Fiorentino, FI, Italy
| | - Rita Baraldi
- Institute of BioEconomy, National Research Council, Bologna, Italy
| | - Luisa Neri
- Center Agriculture Food Environment (C3A), University of Trento, via E. Mach 1, San Michele all'Adige, 38010, Italy
| | - Gerardo Puopolo
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, San Michele all'Adige, 38010, Italy
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Moore-Colyer M, Longland A, Harris P, Zeef L, Crosthwaite S. Mapping the bacterial ecology on the phyllosphere of dry and post soaked grass hay for horses. PLoS One 2020; 15:e0227151. [PMID: 31986161 PMCID: PMC6984722 DOI: 10.1371/journal.pone.0227151] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 12/11/2019] [Indexed: 12/24/2022] Open
Abstract
Soaking hay fodder to reduce dust and soluble carbohydrate (WSC) contents prior to feeding is common practice among horse owners. Soaking can increase bacteria load in hay but no information exists on how this process alters the bacteria profile, which could pose a health risk or digestive challenge, to horses by introducing foreign bacteria into the gastrointestinal tract and so altering the normal profile. The current objectives were to map the bacterial profile of 3 different hays and determine how soaking alters this with the aim of improving best practice when feeding stabled horses. A Perennial Rye grass hay and two meadow s hays were soaked for 0, 1.5, 9 or 16 hours. Pre and post treatment, hays were analysed for WSC and total aerobic bacteria (CFU/g), and differences in bacteria family profiles were determined using ANOVA with significance set at P<0.05. Bacteria were identified via genomic DNA extraction and 16S library preparation (V3 and V4 variable region of 16S rRNA) according to the Illumina protocol. Differences in family operational taxonomic units (OTUs) between individual dry hays and different soaking times were identified via paired t-tests on the DESeq2 normalised data and false discovery rates accounted for using Padj (P<0.05). Mean % WSC losses and actual g/kg lost on DM basis (+/- SE) increased with soaking time being 18% = 30 (10.7), 38% = 72 (43.7), and 42% = 80 (38.8) for 1.5, 9 and 16 hours soak respectively. No relationship existed between WSC leaching and bacteria growth or profile. Grass type influenced bacterial profiles and their responses to soaking, but no differences were seen in richness or Shannon diversity indices. PCA analyses showed clustering of bacteria between meadow hays which differed from the perennial rye grass hay and this difference increased post soaking. Soaking hay pre-feeding causes inconsistent WSC leaching, bacteria growth and alterations in bacterial profiles which are unpredictable but may decrease the hygienic quality of the fodder.
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Affiliation(s)
- Meriel Moore-Colyer
- School of Equine Management and Science, Royal Agricultural University, Cirencester, Gloucestershire, United Kingdom
- * E-mail:
| | - Annette Longland
- Equine and Livestock Nutrition Services, Tregaron, Ceredigion, Wales
| | - Patricia Harris
- Mars Horsecare United Kingdom LTD; Equine Studies Group, WALTHAM Centre for Pet Nutrition, Leicestershire, United Kingdom
| | - Leo Zeef
- Faculty of Biology, Medicine and Health, University of Manchester, United Kingdom
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Hernandez MN, Lindow SE. Pseudomonas syringae Increases Water Availability in Leaf Microenvironments via Production of Hygroscopic Syringafactin. Appl Environ Microbiol 2019; 85:e01014-19. [PMID: 31285194 PMCID: PMC6715840 DOI: 10.1128/aem.01014-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 06/27/2019] [Indexed: 01/26/2023] Open
Abstract
The epiphytic bacterium Pseudomonas syringae strain B728a produces the biosurfactant syringafactin, which is hygroscopic. The water-absorbing potential of syringafactin is high. Syringafactin attracts 250% of its weight in water at high relative humidities but is less hygroscopic at lower relative humidities. This finding suggests that the benefit of syringafactin to the producing cells is strongly context dependent. The contribution of syringafactin to the water availability around cells on different matrices was assessed by examining the water stress exhibited by biosensor strains expressing gfp via the water-stress-activated proU promoter. Wild-type cells exhibited significantly less green fluorescent protein (GFP) fluorescence than a syringafactin-deficient strain on dry filters in atmospheres of high water saturation, as well as on leaf surfaces, indicating greater water availability. When infiltrated into the leaf apoplast, wild-type cells also subsequently exhibited less GFP fluorescence than the syringafactin-deficient strain. These results suggest that the apoplast is a dry but humid environment and that, just as on dry but humid leaf surfaces, syringafactin increases liquid water availability and reduces the water stress experienced by P. syringaeIMPORTANCE Many microorganisms, including the plant pathogen Pseudomonas syringae, produce amphiphilic compounds known as biosurfactants. While biosurfactants are known to disperse hydrophobic compounds and to reduce water tension, they have other properties that can benefit the cells that produce them. Leaf-colonizing bacteria experience frequent water stress, since liquid water is present only transiently on or in leaf sites that they colonize. The demonstration that syringafactin, a biosurfactant produced by P. syringae, is sufficiently hygroscopic to increase water availability to cells, thus relieving water stress, reveals that P. syringae can modify its local habitat both on leaf surfaces and in the leaf apoplast. Such habitat modification may be a common role for biosurfactants produced by other bacterial species that colonize habitats (such as soil) that are not always water saturated.
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Affiliation(s)
- Monica N Hernandez
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, California, USA
| | - Steven E Lindow
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, California, USA
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Oso S, Walters M, Schlechter RO, Remus-Emsermann MNP. Utilisation of hydrocarbons and production of surfactants by bacteria isolated from plant leaf surfaces. FEMS Microbiol Lett 2019; 366:5420820. [DOI: 10.1093/femsle/fnz061] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 03/20/2019] [Indexed: 01/25/2023] Open
Affiliation(s)
- Simisola Oso
- School of Biological Sciences, University of Canterbury, 20 Kirkwood Avenue, Upper Riccarton, 8140 Christchurch, New Zealand
| | - Matthew Walters
- School of Biological Sciences, University of Canterbury, 20 Kirkwood Avenue, Upper Riccarton, 8140 Christchurch, New Zealand
| | - Rudolf O Schlechter
- School of Biological Sciences, University of Canterbury, 20 Kirkwood Avenue, Upper Riccarton, 8140 Christchurch, New Zealand
- Biomolecular Interaction Centre, University of Canterbury, 20 Kirkwood Avenue, Upper Riccarton, 8140 Christchurch, New Zealand
| | - Mitja N P Remus-Emsermann
- School of Biological Sciences, University of Canterbury, 20 Kirkwood Avenue, Upper Riccarton, 8140 Christchurch, New Zealand
- Biomolecular Interaction Centre, University of Canterbury, 20 Kirkwood Avenue, Upper Riccarton, 8140 Christchurch, New Zealand
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13
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Berry ZC, Emery NC, Gotsch SG, Goldsmith GR. Foliar water uptake: Processes, pathways, and integration into plant water budgets. PLANT, CELL & ENVIRONMENT 2019; 42:410-423. [PMID: 30194766 DOI: 10.1111/pce.13439] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/27/2018] [Accepted: 08/28/2018] [Indexed: 05/04/2023]
Abstract
Nearly all plant families, represented across most major biomes, absorb water directly through their leaves. This phenomenon is commonly referred to as foliar water uptake. Recent studies have suggested that foliar water uptake provides a significant water subsidy that can influence both plant water and carbon balance across multiple spatial and temporal scales. Despite this, our mechanistic understanding of when, where, how, and to what end water is absorbed through leaf surfaces remains limited. We first review the evidence for the biophysical conditions necessary for foliar water uptake to occur, focusing on the plant and atmospheric water potentials necessary to create a gradient for water flow. We then consider the different pathways for uptake, as well as the potential fates of the water once inside the leaf. Given that one fate of water from foliar uptake is to increase leaf water potentials and contribute to the demands of transpiration, we also provide a quantitative synthesis of observed rates of change in leaf water potential and total fluxes of water into the leaf. Finally, we identify critical research themes that should be addressed to effectively incorporate foliar water uptake into traditional frameworks of plant water movement.
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Affiliation(s)
- Z Carter Berry
- Schmid College of Science and Technology, Chapman University, Orange, California, USA
| | - Nathan C Emery
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, USA
| | - Sybil G Gotsch
- Department of Biology, Franklin and Marshall College, Lancaster, Pennsylvania, USA
| | - Gregory R Goldsmith
- Schmid College of Science and Technology, Chapman University, Orange, California, USA
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14
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Liang W, Yu A, Wang G, Zheng F, Hu P, Jia J, Xu H. A novel water-based chitosan-La pesticide nanocarrier enhancing defense responses in rice (Oryza sativa L) growth. Carbohydr Polym 2018; 199:437-444. [DOI: 10.1016/j.carbpol.2018.07.042] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 07/12/2018] [Accepted: 07/13/2018] [Indexed: 12/29/2022]
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15
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Wang G, Xiao Y, Xu H, Hu P, Liang W, Xie L, Jia J. Development of Multifunctional Avermectin Poly(succinimide) Nanoparticles to Improve Bioactivity and Transportation in Rice. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:11244-11253. [PMID: 30299946 DOI: 10.1021/acs.jafc.8b03295] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Avermectin (AVM) as a nonsystemic pesticide possesses a low effective utilization rate. Studies of the multifunctional pesticide delivery system for improving biological activity are developing prosperously. In this study, multifunctional avermectin/polysuccinimide with glycine methyl ester nanoparticles (AVM-PGA) were prepared by the self-assembly process. The AVM loading capacity was up to 23.7%. After 24 h of UV irradiation, there was still about 70% of AVM remaining in PGA42 nanocarriers, as opposed to less than 5% of the free-form AVM. The rising ambient pH promoted the release of AVM using an in vitro releasing test, revealing a favorable pH-responsively controlled-release property. The mortality rate of Plutella xylostella with 2.5 μg/mL of AVM content of AVM-PGA42 was 96.3% after 48 h, while that of free AVM was only 51.5%. In addition, the AVM could be detected in stems and all leaves treated with AVM-PGA42 nanoparticles, whereas rare AVM was detected only in treated leaves for the free-form AVM, which achieved the transportation of nanocarriers carrying AVM in rice for the first time. Furthermore, the PGA nanoparticles performed a good growth promoting effect on rice. These results show that the AVM-PGA42 nanopesticides have a great potential application prospect to control the pest and improve the drug utilization efficiency on agriculture.
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Affiliation(s)
- Guodong Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources , South China Agricultural University , Guangzhou , Guangdong 510642 , China
- College of Materials and Energy , South China Agricultural University , Guangzhou , Guangdong 510642 , China
| | - Yuyan Xiao
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources , South China Agricultural University , Guangzhou , Guangdong 510642 , China
| | - Hanhong Xu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources , South China Agricultural University , Guangzhou , Guangdong 510642 , China
| | - Pengtong Hu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources , South China Agricultural University , Guangzhou , Guangdong 510642 , China
- College of Materials and Energy , South China Agricultural University , Guangzhou , Guangdong 510642 , China
| | - Wenlong Liang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources , South China Agricultural University , Guangzhou , Guangdong 510642 , China
| | - Lijuan Xie
- College of Materials and Energy , South China Agricultural University , Guangzhou , Guangdong 510642 , China
| | - Jinliang Jia
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources , South China Agricultural University , Guangzhou , Guangdong 510642 , China
- College of Materials and Energy , South China Agricultural University , Guangzhou , Guangdong 510642 , China
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16
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Garay LA, Sitepu IR, Cajka T, Xu J, Teh HE, German JB, Pan Z, Dungan SR, Block DE, Boundy-Mills KL. Extracellular fungal polyol lipids: A new class of potential high value lipids. Biotechnol Adv 2018; 36:397-414. [DOI: 10.1016/j.biotechadv.2018.01.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 12/07/2017] [Accepted: 01/03/2018] [Indexed: 01/30/2023]
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17
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Panchal S, Melotto M. Stomate-based defense and environmental cues. PLANT SIGNALING & BEHAVIOR 2017; 12:e1362517. [PMID: 28816601 PMCID: PMC5640185 DOI: 10.1080/15592324.2017.1362517] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/25/2017] [Accepted: 07/27/2017] [Indexed: 05/24/2023]
Abstract
Environmental conditions play crucial roles in modulating immunity and disease in plants. For instance, many bacterial disease outbreaks occur after periods of high humidity and rain. A critical step in bacterial infection is entry into the plant interior through wounds or natural openings, such as stomata. Bacterium-triggered stomatal closure is an integral part of the plant immune response to reduce pathogen invasion. Recently, we found that high humidity compromises stomatal defense, which is accompanied by regulation of the salicylic acid and jasmonic acid pathways in guard cells. Periods of darkness, when most stomata are closed, are effective in decreasing pathogen penetration into leaves. However, coronatine produced by Pseudomonas syringae pv. tomato (Pst) DC3000 cells can open dark-closed stomata facilitating infection. Thus, a well-known disease-promoting environmental condition (high humidity) acts in part by suppressing stomatal defense, whereas an anti-stomatal defense factor such as coronatine, may provide epidemiological advantages to ensure bacterial infection when environmental conditions (darkness and insufficient humidity) favor stomatal defense.
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Affiliation(s)
- Shweta Panchal
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Maeli Melotto
- Department of Plant Sciences, University of California, Davis, CA, USA
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18
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Thapa S, Prasanna R, Ranjan K, Velmourougane K, Ramakrishnan B. Nutrients and host attributes modulate the abundance and functional traits of phyllosphere microbiome in rice. Microbiol Res 2017; 204:55-64. [PMID: 28870292 DOI: 10.1016/j.micres.2017.07.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 07/11/2017] [Accepted: 07/15/2017] [Indexed: 02/04/2023]
Abstract
The abundance of phyllosphere bacterial communities of seven genotypes of rice ADT- 38, ADT-43, CR-1009, PB-1, PS-5, P-44, and PB-1509 was investigated, in relation to nutrient dynamics of rhizosphere and leaves. P-44 genotype recorded highest pigment accumulation, while genotypes CR-1009 and P-44 exhibited most number of different bacterial morphotypes, Colony forming units in two media (Nutrient agar and R2A) varied significantly and ranged from 106-107 per g plant tissues. Among the selected 60 distinct morphotypes, IAA and siderophore producers were the dominant functional types. Biocontrol activity against Drechslera oryzae was shown by 38 isolates, while 17 and 9 isolates were potent against Rhizoctonia solani and Magnaporthe oryzae respectively. Principal Component Analysis (PCA) illustrated the significant effects of selected soil and leaf nutrients of seven rice varieties on the culturable phyllospheric population (log CFU), particularly in the R2A medium. Eigen values revealed that 83% of the variance observed could be assigned to Leaf-Fe, Leaf-Mn, chlorophyll b and soil organic carbon (OC). Quantitative PCR analyses of abundance of bacteria, cyanobacteria and archaebacteria revealed a host-specific response, with CR-1009 showing highest number of 16S rRNA copies of bacterial members, while both P-44 and PS-5 had higher cyanobacterial abundance, but lowest number of those belonging to archaebacteria. Nutritional aspects of leaf and soil influenced the abundance of bacteria and their functional attributes; this is of interest for enhancing the efficacy of foliar inoculants, thereby, improving plant growth and disease tolerance.
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Affiliation(s)
- Shobit Thapa
- Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
| | - Radha Prasanna
- Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India.
| | - Kunal Ranjan
- Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India
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19
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Simultaneous production of intracellular triacylglycerols and extracellular polyol esters of fatty acids by Rhodotorula babjevae and Rhodotorula aff. paludigena. J Ind Microbiol Biotechnol 2017; 44:1397-1413. [PMID: 28681129 DOI: 10.1007/s10295-017-1964-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 06/17/2017] [Indexed: 12/11/2022]
Abstract
Microbial oils have been analyzed as alternatives to petroleum. However, just a handful of microbes have been successfully adapted to produce chemicals that can compete with their petroleum counterparts. One of the reasons behind the low success rate is the overall economic inefficiency of valorizing a single product. This study presents a lab-scale analysis of two yeast species that simultaneously produce multiple high-value bioproducts: intracellular triacylglycerols (TG) and extracellular polyol esters of fatty acids (PEFA), two lipid classes with immediate applications in the biofuels and surfactant industries. At harvest, the yeast strain Rhodotorula aff. paludigena UCDFST 81-84 secreted 20.9 ± 0.2 g L-1 PEFA and produced 8.8 ± 1.0 g L-1 TG, while the yeast strain Rhodotorula babjevae UCDFST 04-877 secreted 11.2 ± 1.6 g L-1 PEFA and 18.5 ± 1.7 g L-1 TG. The overall glucose conversion was 0.24 and 0.22 g(total lipid) g (glucose)-1 , respectively. The results present a stable and scalable microbial growth platform yielding multiple co-products.
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20
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Garay LA, Sitepu IR, Cajka T, Fiehn O, Cathcart E, Fry RW, Kanti A, Joko Nugroho A, Faulina SA, Stephanandra S, German JB, Boundy-Mills KL. Discovery of synthesis and secretion of polyol esters of fatty acids by four basidiomycetous yeast species in the order Sporidiobolales. J Ind Microbiol Biotechnol 2017; 44:923-936. [PMID: 28289902 DOI: 10.1007/s10295-017-1919-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 02/05/2017] [Indexed: 12/22/2022]
Abstract
Polyol esters of fatty acids (PEFA) are amphiphilic glycolipids produced by yeast that could play a role as natural, environmentally friendly biosurfactants. We recently reported discovery of a new PEFA-secreting yeast species, Rhodotorula babjevae, a basidiomycetous yeast to display this behavior, in addition to a few other Rhodotorula yeasts reported on the 1960s. Additional yeast species within the taxonomic order Sporidiobolales were screened for secreted glycolipid production. PEFA production equal or above 1 g L-1 were detected in 19 out of 65 strains of yeast screened, belonging to 6 out of 30 yeast species tested. Four of these species were not previously known to secrete glycolipids. These results significantly increase the number of yeast species known to secrete PEFA, holding promise for expanding knowledge of PEFA synthesis and secretion mechanisms, as well as setting the groundwork towards commercialization.
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Affiliation(s)
- Luis A Garay
- Phaff Yeast Culture Collection, Department of Food Science and Technology, University of California, One Shields Ave, Davis, CA, 95616-8598, USA
| | - Irnayuli R Sitepu
- Phaff Yeast Culture Collection, Department of Food Science and Technology, University of California, One Shields Ave, Davis, CA, 95616-8598, USA.,Biotechnology Department, Indonesia International Institute for Life Sciences (i3L), Jalan Pulo Mas Barat Kav. 88, Jakarta, 13210, Indonesia
| | - Tomas Cajka
- West Coast Metabolomics Center, Genome Center, University of California, 451 Health Sciences Drive, Davis, CA, 95616, USA
| | - Oliver Fiehn
- West Coast Metabolomics Center, Genome Center, University of California, 451 Health Sciences Drive, Davis, CA, 95616, USA.,Biochemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589, Saudi Arabia
| | - Erin Cathcart
- Phaff Yeast Culture Collection, Department of Food Science and Technology, University of California, One Shields Ave, Davis, CA, 95616-8598, USA
| | - Russell W Fry
- Phaff Yeast Culture Collection, Department of Food Science and Technology, University of California, One Shields Ave, Davis, CA, 95616-8598, USA
| | - Atit Kanti
- Research Center for Biology, Indonesian Institute of Sciences, Jalan Raya Jakarta - Bogor Km.46 Cibinong, Bogor, 16911, Indonesia
| | - Agustinus Joko Nugroho
- Research Center for Biology, Indonesian Institute of Sciences, Jalan Raya Jakarta - Bogor Km.46 Cibinong, Bogor, 16911, Indonesia
| | - Sarah Asih Faulina
- Research, Development and Innovation Agency, Ministry of Environment and Forestry, Jalan Gunung Batu No. 5, P.O. Box 165, Bogor, 16610, Indonesia
| | - Sira Stephanandra
- Research, Development and Innovation Agency, Ministry of Environment and Forestry, Jalan Gunung Batu No. 5, P.O. Box 165, Bogor, 16610, Indonesia
| | - J Bruce German
- Department of Food Science and Technology, University of California Davis, One Shields Avenue, Davis, CA, 95616, USA
| | - Kyria L Boundy-Mills
- Phaff Yeast Culture Collection, Department of Food Science and Technology, University of California, One Shields Ave, Davis, CA, 95616-8598, USA.
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21
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Wu S, Zhao B. Using Clear Nail Polish to Make Arabidopsis Epidermal Impressions for Measuring the Change of Stomatal Aperture Size in Immune Response. Methods Mol Biol 2017; 1578:243-248. [PMID: 28220430 DOI: 10.1007/978-1-4939-6859-6_20] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Plant stomata are an essential route for bacterial pathogens to entry inside host tissue and cause diseases. As an important defense mechanism, plant stomata can actively restrict bacterial invasion by dynamically regulating the opening, closing, and reopening of stomatal guard cells. Therefore, accurately measuring the stomatal aperture size during the bacterial pathogenesis is an important approach to study the stomata related immunity. Several methods have been developed for stomatal aperture measurement. Here, we described a detailed protocol of using clear nail polish to make Arabidopsis epidermal impressions for investigate the change of stomatal aperture size in plant immune response. The application of this approach can instantly fix the status of stomatal guard cells, and provides clear, stable, and almost permanent slides of epidermal impressions for measurement of stomatal aperture size.
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Affiliation(s)
- Shuchi Wu
- Department of Horticulture, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Bingyu Zhao
- Department of Horticulture, Virginia Tech, Blacksburg, VA, 24061, USA.
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22
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High-Level Culturability of Epiphytic Bacteria and Frequency of Biosurfactant Producers on Leaves. Appl Environ Microbiol 2016; 82:5997-6009. [PMID: 27474719 DOI: 10.1128/aem.01751-16] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 07/25/2016] [Indexed: 12/20/2022] Open
Abstract
UNLABELLED To better characterize the bacterial community members capable of biosurfactant production on leaves, we distinguished culturable biosurfactant-producing bacteria from nonproducers and used community sequencing to compare the composition of these distinct cultured populations with that from DNA directly recovered from leaves. Communities on spinach, romaine, and head lettuce leaves were compared with communities from adjacent samples of soil and irrigation source water. Soil communities were poorly described by culturing, with recovery of cultured representatives from only 21% of the prevalent operational taxonomic units (OTUs) (>0.2% reads) identified. The dominant biosurfactant producers cultured from soil included bacilli and pseudomonads. In contrast, the cultured communities from leaves are highly representative of the culture-independent communities, with over 85% of the prevalent OTUs recovered. The dominant taxa of surfactant producers from leaves were pseudomonads as well as members of the infrequently studied genus Chryseobacterium The proportions of bacteria cultured from head lettuce and romaine leaves that produce biosurfactants were directly correlated with the culture-independent proportion of pseudomonads in a given sample, whereas spinach harbored a wider diversity of biosurfactant producers. A subset of the culturable bacteria in irrigation water also became enriched on romaine leaves that were irrigated overhead. Although our study was designed to identify surfactant producers on plants, we also provide evidence that most bacteria in some habitats, such as agronomic plant surfaces, are culturable, and these communities can be readily investigated and described by more classical culturing methods. IMPORTANCE The importance of biosurfactant production to the bacteria that live on waxy leaf surfaces as well as their ability to be accurately assessed using culture-based methodologies was determined by interrogating epiphytic populations by both culture-dependent and culture-independent methods. Biosurfactant production was much more frequently observed in cultured communities on leaves than in other nearby habitats, such as soil and water, suggesting that this trait is important to life on a leaf by altering either the leaf itself or the interaction of bacteria with water. While pseudomonads were the most common biosurfactant producers isolated, this habitat also selects for taxa, such as Chryseobacterium, for which this trait was previously unrecognized. The finding that most epiphytic bacterial taxa were culturable validates strategies using more classical culturing methodologies for their study in this habitat.
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Nasanit R, Jaibangyang S, Tantirungkij M, Limtong S. Yeast diversity and novel yeast D1/D2 sequences from corn phylloplane obtained by a culture-independent approach. Antonie van Leeuwenhoek 2016; 109:1615-1634. [PMID: 27578202 DOI: 10.1007/s10482-016-0762-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 08/23/2016] [Indexed: 02/07/2023]
Abstract
Culture-independent techniques have recently been used for evaluation of microbial diversity in the environment since it addresses the problem of unculturable microorganisms. In this study, the diversity of epiphytic yeasts from corn (Zea mays Linn.) phylloplanes in Thailand was investigated using this technique and sequence-based analysis of the D1/D2 domains of the large subunit ribosomal DNA sequences. Thirty-seven samples of corn leaf were collected randomly from 10 provinces. The DNA was extracted from leaf washing samples and the D1/D2 domains were amplified. The PCR products were cloned and then screened by colony PCR. A total of 1049 clones were obtained from 37 clone libraries. From this total, 329 clones (213 sequences) were closely related to yeast strains in the GenBank database, and they were clustered into 77 operational taxonomic units (OTUs) with a similarity threshold of 99 %. The majority of sequences (98.5 %) were classified into the phylum Basidiomycota. Sixteen known yeast species were identified. Interestingly, more than 65 % of the D1/D2 sequences obtained by this technique were suggested to be sequences from new yeast taxa. The predominant yeast sequences detected belonged to the order Ustilaginales with relative frequency of 68.0 %. The most common known yeast species detected on the leaf samples were Pseudozyma hubeiensis pro tem. and Moesziomyces antarcticus with frequency of occurrence of 24.3 and 21.6 %, respectively.
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Affiliation(s)
- Rujikan Nasanit
- Department of Biotechnology, Faculty of Engineering and Industrial Technology, Silpakorn University, Sanamchandra Palace Campus, Amphoe Muang, Nakhon Pathom, 73000, Thailand
| | - Sopin Jaibangyang
- Department of Biotechnology, Faculty of Engineering and Industrial Technology, Silpakorn University, Sanamchandra Palace Campus, Amphoe Muang, Nakhon Pathom, 73000, Thailand
| | - Manee Tantirungkij
- Central Laboratory and Greenhouse Complex, Faculty of Agriculture at Kamphaeng Sean, Kasetsart University, Kamphaeng Sean Campus, Kamphaeng Saen, Nakhon Pathom, 73140, Thailand
| | - Savitree Limtong
- Department of Microbiology, Faculty of Science, Kasetsart University, Jatujak, Bangkok, 10900, Thailand. .,Center for Advanced Studies in Tropical Natural Resources, National Research University-Kasetsart University, Bangkok, 10900, Thailand.
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24
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Qin Y, Fu Y, Dong C, Jia N, Liu H. Shifts of microbial communities of wheat (Triticum aestivum L.) cultivation in a closed artificial ecosystem. Appl Microbiol Biotechnol 2016; 100:4085-95. [DOI: 10.1007/s00253-016-7317-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 01/07/2016] [Accepted: 01/10/2016] [Indexed: 01/22/2023]
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25
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Deepika K, Ramu Sridhar P, Bramhachari P. Characterization and antifungal properties of rhamnolipids produced by mangrove sediment bacterium Pseudomonas aeruginosa strain KVD-HM52. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2015. [DOI: 10.1016/j.bcab.2015.09.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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26
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Nasanit R, Tangwong-O-Thai A, Tantirungkij M, Limtong S. The assessment of epiphytic yeast diversity in sugarcane phyllosphere in Thailand by culture-independent method. Fungal Biol 2015; 119:1145-1157. [PMID: 26615738 DOI: 10.1016/j.funbio.2015.08.021] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 08/28/2015] [Accepted: 08/31/2015] [Indexed: 11/27/2022]
Abstract
The diversity of epiphytic yeasts from sugarcane (Saccharum officinarum Linn.) phyllospheres in Thailand was investigated by culture-independent method based on the analysis of the D1/D2 domains of the large subunit rRNA gene sequences. Forty-five samples of sugarcane leaf were collected randomly from ten provinces in Thailand. A total of 1342 clones were obtained from 45 clone libraries. 426 clones (31.7 %) were closely related to yeast strains in the GenBank database, and they were clustered into 31 operational taxonomic units (OTUs) with a similarity threshold of 99 %. All OTU sequences were classified in phylum Basidiomycota which were closely related to 11 yeast species in seven genera including Cryptococcus flavus, Hannaella coprosmaensis, Rhodotorula taiwanensis, Jaminaea angkoreiensis, Malassezia restricta, Pseudozyma antarctica, Pseudozyma aphidis, Pseudozyma hubeiensis, Pseudozyma prolifica, Pseudozyma shanxiensis, and Sporobolomyces vermiculatus. The most predominant yeasts detected belonged to Ustilaginales with 89.4 % relative frequency and the prevalent yeast genus was Pseudozyma. However, the majority were unable to be identified as known yeast species and these sequences may represent the sequences of new yeast taxa. In addition, The OTU that closely related to P. prolifica was commonly detected in sugarcane phyllosphere.
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Affiliation(s)
- Rujikan Nasanit
- Department of Biotechnology, Faculty of Engineering and Industrial Technology, Silpakorn University, Sanamchandra Palace Campus, Nakhon Pathom 73000, Thailand
| | - Apirat Tangwong-O-Thai
- Department of Biotechnology, Faculty of Engineering and Industrial Technology, Silpakorn University, Sanamchandra Palace Campus, Nakhon Pathom 73000, Thailand
| | - Manee Tantirungkij
- Central Laboratory and Greenhouse Complex, Faculty of Agriculture at Kamphaeng Sean, Kasetsart University, Kamphaeng Sean Campus, Nakhon Pathom 73140, Thailand
| | - Savitree Limtong
- Department of Microbiology, Faculty of Science, Kasetsart University, Jatujak, Bangkok 10900, Thailand; Center for Advanced Studies in Tropical Natural Resources, National Research University-Kasetsart University, Bangkok 10900, Thailand.
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27
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Nasanit R, Krataithong K, Tantirungkij M, Limtong S. Assessment of epiphytic yeast diversity in rice (Oryza sativa) phyllosphere in Thailand by a culture-independent approach. Antonie van Leeuwenhoek 2015; 107:1475-90. [PMID: 25842038 DOI: 10.1007/s10482-015-0442-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 03/26/2015] [Indexed: 01/14/2023]
Abstract
The epiphytic yeast diversity in rice phyllosphere in Thailand was investigated by a culture-independent technique based on the RFLP pattern and the sequence of the D1/D2 domain of the large subunit rRNA gene. Forty-four samples of rice leaf were collected randomly from six provinces. The DNA was extracted from leaf washing samples and the D1/D2 domain was amplified using PCR technique. The PCR products were cloned and then screened by colony PCR. Of total 1121 clones, 451 clones (40.2 %) revealed the D1/D2 domain sequences closely related to sequences of yeasts in GenBank, and they were clustered into 45 operational taxonomic units (OTUs) at 99 % homology. Of total yeast related clones, 329 clones (72.9 %) were identified as nine known yeast species, which consisted of 314 clones (8 OTUs) in the phylum Basidiomycota including Bullera japonica, Pseudozyma antarctica, Pseudozyma aphidis, Sporobolomyces blumeae, Sporobolomyces carnicolor and Sporobolomyces oryzicola and 15 clones (6 OTUs) in the phylum Ascomycota including Metschnikowia koreensis, Meyerozyma guilliermondii and Wickerhamomyces anomalus. The D1/D2 sequences (122 clones) that could not be identified as known yeast species were closest to 3 and 14 species in Ascomycota and Basidiomycota, respectively, some of which may be new yeast species. The most predominant species detected was P. antarctica (42.6 %) followed by B. japonica (25.9 %) with 63.6 and 22.7 % frequency of occurrence, respectively. The results of OTU richness of each sampling location revealed that climate condition and sampling location could affect epiphytic yeast diversity in rice phyllosphere.
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Affiliation(s)
- Rujikan Nasanit
- Department of Biotechnology, Faculty of Engineering and Industrial Technology, Silpakorn University, Sanamchandra palace campus, Nakhon Pathom, 73000, Thailand
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Microbial Life on Green Biomass and Their Use for Production of Platform Chemicals. MICROORGANISMS IN BIOREFINERIES 2015. [DOI: 10.1007/978-3-662-45209-7_2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Trouvelot S, Héloir MC, Poinssot B, Gauthier A, Paris F, Guillier C, Combier M, Trdá L, Daire X, Adrian M. Carbohydrates in plant immunity and plant protection: roles and potential application as foliar sprays. FRONTIERS IN PLANT SCIENCE 2014; 5:592. [PMID: 25408694 PMCID: PMC4219568 DOI: 10.3389/fpls.2014.00592] [Citation(s) in RCA: 158] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 10/11/2014] [Indexed: 05/18/2023]
Abstract
Increasing interest is devoted to carbohydrates for their roles in plant immunity. Some of them are elicitors of plant defenses whereas other ones act as signaling molecules in a manner similar to phytohormones. This review first describes the main classes of carbohydrates associated to plant immunity, their role and mode of action. More precisely, the state of the art about perception of "PAMP, MAMP, and DAMP (Pathogen-, Microbe-, Damage-Associated Molecular Patterns) type" oligosaccharides is presented and examples of induced defense events are provided. A particular attention is paid to the structure/activity relationships of these compounds. The role of sugars as signaling molecules, especially in plant microbe interactions, is also presented. Secondly, the potentialities and limits of foliar sprays of carbohydrates to stimulate plant immunity for crop protection against diseases are discussed, with focus on the roles of the leaf cuticle and phyllosphere microflora.
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Affiliation(s)
- Sophie Trouvelot
- Université de Bourgogne, UMR AgroSup/INRA/uB 1347 Agroécologie, Pôle Interactions Plantes-Microorganismes-ERL CNRS 6300Dijon, France
| | - Marie-Claire Héloir
- Université de Bourgogne, UMR AgroSup/INRA/uB 1347 Agroécologie, Pôle Interactions Plantes-Microorganismes-ERL CNRS 6300Dijon, France
| | - Benoît Poinssot
- Université de Bourgogne, UMR AgroSup/INRA/uB 1347 Agroécologie, Pôle Interactions Plantes-Microorganismes-ERL CNRS 6300Dijon, France
| | - Adrien Gauthier
- Department of Biosciences, Plant Biology, University of HelsinkiHelsinki, Finland
| | - Franck Paris
- Université de Bourgogne, UMR AgroSup/INRA/uB 1347 Agroécologie, Pôle Interactions Plantes-Microorganismes-ERL CNRS 6300Dijon, France
| | - Christelle Guillier
- Université de Bourgogne, UMR AgroSup/INRA/uB 1347 Agroécologie, Pôle Interactions Plantes-Microorganismes-ERL CNRS 6300Dijon, France
| | - Maud Combier
- Université de Bourgogne, UMR AgroSup/INRA/uB 1347 Agroécologie, Pôle Interactions Plantes-Microorganismes-ERL CNRS 6300Dijon, France
| | - Lucie Trdá
- Université de Bourgogne, UMR AgroSup/INRA/uB 1347 Agroécologie, Pôle Interactions Plantes-Microorganismes-ERL CNRS 6300Dijon, France
| | - Xavier Daire
- INRA, UMR AgroSup/INRA/uB 1347 Agroécologie, Pôle Interactions Plantes-Microorganismes-ERL CNRS 6300Dijon, France
| | - Marielle Adrian
- Université de Bourgogne, UMR AgroSup/INRA/uB 1347 Agroécologie, Pôle Interactions Plantes-Microorganismes-ERL CNRS 6300Dijon, France
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Williams TR, Marco ML. Phyllosphere microbiota composition and microbial community transplantation on lettuce plants grown indoors. mBio 2014; 5:e01564-14. [PMID: 25118240 PMCID: PMC4145687 DOI: 10.1128/mbio.01564-14] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 07/09/2014] [Indexed: 11/23/2022] Open
Abstract
UNLABELLED The aerial surfaces of plants, or phyllosphere, are microbial habitats important to plant and human health. In order to accurately investigate microbial interactions in the phyllosphere under laboratory conditions, the composition of the phyllosphere microbiota should be representative of the diversity of microorganisms residing on plants in nature. We found that Romaine lettuce grown in the laboratory contained 10- to 100-fold lower numbers of bacteria than age-matched, field-grown lettuce. The bacterial diversity on laboratory-grown plants was also significantly lower and contained relatively higher proportions of Betaproteobacteria as opposed to the Gammaproteobacteria-enriched communities on field lettuce. Incubation of field-grown Romaine lettuce plants in environmental growth chambers for 2 weeks resulted in bacterial cell densities and taxa similar to those on plants in the field but with less diverse bacterial populations overall. In comparison, the inoculation of laboratory-grown Romaine lettuce plants with either freshly collected or cryopreserved microorganisms recovered from field lettuce resulted in the development of a field-like microbiota on the lettuce within 2 days of application. The survival of an inoculated strain of Escherichia coli O157:H7 was unchanged by microbial community transfer; however, the inoculation of E. coli O157:H7 onto those plants resulted in significant shifts in the abundance of certain taxa. This finding was strictly dependent on the presence of a field-associated as opposed to a laboratory-associated microbiota on the plants. Phyllosphere microbiota transplantation in the laboratory will be useful for elucidating microbial interactions on plants that are important to agriculture and microbial food safety. IMPORTANCE The phyllosphere is a habitat for a variety of microorganisms, including bacteria with significant relevance to plant and human health. Some indigenous epiphytic bacteria might affect the persistence of human food-borne pathogens in the phyllosphere. However, studies on human pathogens are typically performed on plants grown indoors. This study compares the phyllosphere microbiota on Romaine lettuce plants grown in a Salinas Valley, CA, field to that on lettuce plants grown in environmental chambers. We show that phyllosphere microbiota from laboratory-grown plants is distinct from that colonizing plants grown in the field and that the field microbiota can be successfully transferred to plants grown indoors. The microbiota transplantation method was used to examine alterations to the phyllosphere microbiota after Escherichia coli O157:H7 inoculation on lettuce plants in a controlled environment. Our findings show the importance and validity of phyllosphere microbiota transplantation for future phyllosphere microbiology research.
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Affiliation(s)
- Thomas R Williams
- Department of Food Science & Technology, University of California, Davis, California, USA
| | - Maria L Marco
- Department of Food Science & Technology, University of California, Davis, California, USA
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Burch AY, Zeisler V, Yokota K, Schreiber L, Lindow SE. The hygroscopic biosurfactant syringafactin produced by Pseudomonas syringae enhances fitness on leaf surfaces during fluctuating humidity. Environ Microbiol 2014; 16:2086-98. [PMID: 24571678 DOI: 10.1111/1462-2920.12437] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 02/18/2014] [Indexed: 11/27/2022]
Abstract
Biosurfactant production by bacteria on leaf surfaces is poorly documented, and its role in this habitat has not been explored. Therefore, we investigated the production and fitness benefits of syringafactin by Pseudomonas syringae pv. syringae B728a on leaves. Syringafactin largely adsorbed to the waxy leaf cuticle both when topically applied and when produced by cells on plants. Syringafactin increased the rate of diffusion of water across isolated cuticles and attracted water to hydrophobic surfaces exposed to high relative humidity due to its hygroscopic properties. While a wild-type and syringafactin mutant exhibited similar fitness on bean leaves incubated in static conditions, the fitness of the wild-type strain was higher under fluctuating humidity conditions typical of field conditions. When co-inoculated onto either the host plant bean or the non-host plant romaine lettuce, the proportion of viable wild-type cells recovered from plants relative to that of a mutant unable to produce syringafactin increased 10% over 10 days. The number of disease lesions incited by the wild-type strain on bean was also significantly higher than that of the syringafactin mutant. The production of hygroscopic biosurfactants on waxy leaf surfaces apparently benefits bacteria by both attracting moisture and facilitating access to nutrients.
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Affiliation(s)
- Adrien Y Burch
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA
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van der Wal A, Tecon R, Kreft JU, Mooij WM, Leveau JHJ. Explaining bacterial dispersion on leaf surfaces with an individual-based model (PHYLLOSIM). PLoS One 2013; 8:e75633. [PMID: 24124501 PMCID: PMC3790818 DOI: 10.1371/journal.pone.0075633] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 08/18/2013] [Indexed: 11/19/2022] Open
Abstract
We developed the individual-based model PHYLLOSIM to explain observed variation in the size of bacterial clusters on plant leaf surfaces (the phyllosphere). Specifically, we tested how different 'waterscapes' impacted the diffusion of nutrients from the leaf interior to the surface and the growth of individual bacteria on these nutrients. In the 'null' model or more complex 'patchy' models, the surface was covered with a continuous water film or with water drops of equal or different volumes, respectively. While these models predicted the growth of individual bacterial immigrants into clusters of variable sizes, they were unable to reproduce experimentally derived, previously published patterns of dispersion which were characterized by a much larger variation in cluster sizes and a disproportionate occurrence of clusters consisting of only one or two bacteria. The fit of model predictions to experimental data was about equally poor (<5%) regardless of whether the water films were continuous or patchy. Only by allowing individual bacteria to detach from developing clusters and re-attach elsewhere to start a new cluster, did PHYLLOSIM come much closer to reproducing experimental observations. The goodness of fit including detachment increased to about 70-80% for all waterscapes. Predictions of this 'detachment' model were further supported by the visualization and quantification of bacterial detachment and attachment events at an agarose-water interface. Thus, both model and experiment suggest that detachment of bacterial cells from clusters is an important mechanism underlying bacterial exploration of the phyllosphere.
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Affiliation(s)
- Annemieke van der Wal
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
| | - Robin Tecon
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
- Department of Plant Pathology, University of California Davis, Davis, California, United States of America
| | - Jan-Ulrich Kreft
- Centre for Systems Biology, School of Biosciences, The University of Birmingham, Birmingham, United Kingdom
| | - Wolf M. Mooij
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
- Department of Aquatic Ecology and Water Quality Management, Wageningen University, Wageningen, The Netherlands
| | - Johan H. J. Leveau
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
- Department of Plant Pathology, University of California Davis, Davis, California, United States of America
- * E-mail:
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Effects of systemic pesticides imidacloprid and metalaxyl on the phyllosphere of pepper plants. BIOMED RESEARCH INTERNATIONAL 2013; 2013:969750. [PMID: 23841101 PMCID: PMC3690639 DOI: 10.1155/2013/969750] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 05/22/2013] [Indexed: 11/27/2022]
Abstract
Microbes inhabiting the phyllosphere of crops are exposed to pesticides applied either directly onto plant foliage or indirectly through soil. Although, phyllosphere microbiology has been rapidly evolving, little is still known regarding the impact of pesticides on the epiphytic microbial community and especially on fungi. We determined the impact of two systemic pesticides (metalaxyl and imidacloprid), applied either on foliage or through soil, on the epiphytic fungal and bacterial communities via DGGE and cloning. Both pesticides induced mild effects on the fungal and the bacterial communities. The only exception was the foliage application of imidacloprid which showed a more prominent effect on the fungal community. Cloning showed that the fungal community was dominated by putative plant pathogenic ascomycetes (Erysiphaceae and Cladosporium), while a few basidiomycetes were also present. The former ribotypes were not affected by pesticides application, while selected yeasts (Cryptococcus) were stimulated by the application of imidacloprid suggesting a potential role in its degradation. A less diverse bacterial community was identified in pepper plants. Metalaxyl stimulated an Enterobacteriaceae clone which is an indication of the involvement of members of this family in fungicide degradation. Further studies will focus on the isolation of epiphytic microbes which appear to be stimulated by pesticides application.
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Abstract
Our knowledge of the microbiology of the phyllosphere, or the aerial parts of plants, has historically lagged behind our knowledge of the microbiology of the rhizosphere, or the below-ground habitat of plants, particularly with respect to fundamental questions such as which microorganisms are present and what they do there. In recent years, however, this has begun to change. Cultivation-independent studies have revealed that a few bacterial phyla predominate in the phyllosphere of different plants and that plant factors are involved in shaping these phyllosphere communities, which feature specific adaptations and exhibit multipartite relationships both with host plants and among community members. Insights into the underlying structural principles of indigenous microbial phyllosphere populations will help us to develop a deeper understanding of the phyllosphere microbiota and will have applications in the promotion of plant growth and plant protection.
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Affiliation(s)
- Julia A Vorholt
- Institute of Microbiology, ETH Zurich (Swiss Federal Institute of Technology Zurich), Wolfgang-Pauli-Strasse 10, HCI F429, 8093 Zurich, Switzerland.
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Burch AY, Browne PJ, Dunlap CA, Price NP, Lindow SE. Comparison of biosurfactant detection methods reveals hydrophobic surfactants and contact-regulated production. Environ Microbiol 2011; 13:2681-91. [PMID: 21883788 DOI: 10.1111/j.1462-2920.2011.02534.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Biosurfactants are diverse molecules with numerous biological functions and industrial applications. A variety of environments were examined for biosurfactant-producing bacteria including soil, water and leaf surfaces. Biosurfactant production was assessed with an atomized oil assay for a large number of bacterial isolates and compared with a commonly used drop collapse assay from broth and plate cultures. The atomized oil assay detected every strain that produced a biosurfactant detectable by the drop collapse test, and also identified additional strains that were not detected with the drop collapse assay because they produced low levels of surfactant or hydrophobic (low water solubility) surfactants such as pumilacidins. Not all strains that produced a biosurfactant detectable by the drop collapse when cultured on agar surfaces produced surfactants detectable by drop collapse when cultured in broth, and vice versa. Many bacterial strains exhibited preferential production of surfactants when grown on an agar surface compared with broth cultures, and such surface enhancement of production could also be stimulated by increasing the viscosity of liquid culture media. Surface induction of surfactant production in the epiphyte Pseudomonas syringae was regulated at the transcriptional level.
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Affiliation(s)
- Adrien Y Burch
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
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Beattie GA. Water relations in the interaction of foliar bacterial pathogens with plants. ANNUAL REVIEW OF PHYTOPATHOLOGY 2011; 49:533-55. [PMID: 21438680 DOI: 10.1146/annurev-phyto-073009-114436] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
This review examines the many ways in which water influences the relations between foliar bacterial pathogens and plants. As a limited resource in aerial plant tissues, water is subject to manipulation by both plants and pathogens. A model is emerging that suggests that plants actively promote localized desiccation at the infection site and thus restrict pathogen growth as one component of defense. Similarly, many foliar pathogens manipulate water relations as one component of pathogenesis. Nonvascular pathogens do this using effectors and other molecules to alter hormonal responses and enhance intercellular watersoaking, whereas vascular pathogens use many mechanisms to cause wilt. Because of water limitations on phyllosphere surfaces, bacterial colonists, including pathogens, benefit from the protective effects of cellular aggregation, synthesis of hygroscopic polymers, and uptake and production of osmoprotective compounds. Moreover, these bacteria employ tactics for scavenging and distributing water to overcome water-driven barriers to nutrient acquisition, movement, and signal exchange on plant surfaces.
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Affiliation(s)
- Gwyn A Beattie
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, Iowa 50011-3211, USA.
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D'aes J, De Maeyer K, Pauwelyn E, Höfte M. Biosurfactants in plant-Pseudomonas interactions and their importance to biocontrol. ENVIRONMENTAL MICROBIOLOGY REPORTS 2010; 2:359-72. [PMID: 23766108 DOI: 10.1111/j.1758-2229.2009.00104.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Production of biosurfactants is a common feature in bacteria, and in particular in plant-associated species. These bacteria include many plant beneficial and plant pathogenic Pseudomonas spp., which produce primarily cyclic lipopeptide and rhamnolipid type biosurfactants. Pseudomonas-derived biosurfactants are involved in many important bacterial functions. By modifying surface properties, biosurfactants can influence common traits such as surface motility, biofilm formation and colonization. Biosurfactants can alter the bio-availability of exogenous compounds, such as nutrients, to promote their uptake, and of endogenous metabolites, including phenazine antibiotics, resulting in an enhanced biological activity. Antibiotic activity of biosurfactants towards microbes could play a role in intraspecific competition, self-defence and pathogenesis. In addition, bacterial surfactants can affect plants in different ways, either protecting them from disease, or acting as a toxin in a plant-pathogen interaction. Biosurfactants are involved in the biocontrol activity of an increasing number of Pseudomonas strains. Consequently, further insight into the roles and activities of surfactants produced by bacteria could provide means to optimize the use of biological control as an alternative crop protection strategy.
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Affiliation(s)
- Jolien D'aes
- Laboratory of Phytopathology, Faculty of Bioscience Engineering, Ghent University, Coupure Links, 653, B-9000 Ghent, Belgium
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Microbial community on healthy and diseased leaves of an invasive plant Eupatorium adenophorum in Southwest China. J Microbiol 2010; 48:139-45. [PMID: 20437143 DOI: 10.1007/s12275-010-9185-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Accepted: 09/06/2009] [Indexed: 10/19/2022]
Abstract
Invasive plants have caused great economic losses and environmental problems worldwide. Eupatorium adenophorum is one of the most invasive weeds in China. To better understand its invasive mechanisms, in the present paper, the microbial communities of healthy and diseased leaves of E. adenophorum were obtained using both culture-independent and -dependent methods and their diversities were compared. The bacteria obtained from culture-independent method belong to Proteobacteria (95.8%), Actinobacteria (2.1%), and Firmicutes (2.1%) and fungi belong to Ascomycota (65.2%) and Basidiomycota (34.8%). Very few overlapped microbial species were found by culture-dependent and -independent methods. Healthy leaves display higher bacterial diversity than diseased leaves. Phylogenetic structures are very different between healthy and diseased phyllosphere microbial communities. Bacteria close to Acinetobacter and Pseudomonas were dominant on healthy leaves, whereas those close to Shigella were dominant on diseased leaves. 52.9% of fungal clones from healthy leaves were Ustilaginomycetes, close to Rhodotorula phylloplana and uncultured basidomycete; by contrast, 60% of clones from diseased leaves were Lecanoromycetes, close to Umbilicaria muehlenbergii. No bacteria but four fungal strains phylogenetically close to Myrothecium sp. and Alternaria alternate were pathogenic to seedlings and detached leaves of the invasive plant. Therefore, this plant may be resistant to pathogens from bacteria but not fungi in its introduced range.
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Whipps J, Hand P, Pink D, Bending G. Phyllosphere microbiology with special reference to diversity and plant genotype. J Appl Microbiol 2008; 105:1744-55. [DOI: 10.1111/j.1365-2672.2008.03906.x] [Citation(s) in RCA: 332] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Eichert T, Kurtz A, Steiner U, Goldbach HE. Size exclusion limits and lateral heterogeneity of the stomatal foliar uptake pathway for aqueous solutes and water-suspended nanoparticles. PHYSIOLOGIA PLANTARUM 2008; 134:151-60. [PMID: 18494856 DOI: 10.1111/j.1399-3054.2008.01135.x] [Citation(s) in RCA: 241] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Penetration rates of foliar-applied polar solutes are highly variable and the underlying mechanisms are not yet fully understood. The contribution of stomata especially, is still a matter of debate. Thus, the size exclusion limits of the stomatal foliar uptake pathway, its variability and its transport capacity have been investigated. The size exclusion limits were analyzed by studying the penetration of water-suspended hydrophilic particles of two different sizes (43 nm or 1.1 microm diameter) into leaves of Vicia faba (L.). To avoid agglutination of the particles, plants were kept in water-saturated atmosphere. Penetration of the larger particles was never detected, whereas after 2 to 9 days, the smaller particles occasionally penetrated the leaf interior through stomatal pores. Permeability of stomata to Na(2)-fluorescein along the leaf blade of Allium porrum (L.) was highly variable and not correlated with the position on the leaf. When evaporated residues of the foliar-applied solutions were rewetted repeatedly, approximately 60% of the previously penetrated stomata were penetrated again. The average rate constant of penetration of an individual stoma was in the same order of magnitude as typical rate constants reported for the cuticular pathway. The observed sparseness of stomatal penetration together with its high lateral variability but local and temporal persistency was taken as evidence that stomata contributing to uptake differ from non-penetrated ones in the wettability of their guard cell cuticle. These results show that the stomatal pathway is highly capacitive because of its large size exclusion limit above 10 nm and its high transport velocity, but at the same time the high variability renders this pathway largely unpredictable.
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Affiliation(s)
- Thomas Eichert
- Institute of Crop Science and Resource Conservation-Plant Nutrition, University of Bonn, Bonn, Germany.
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Melotto M, Underwood W, He SY. Role of stomata in plant innate immunity and foliar bacterial diseases. ANNUAL REVIEW OF PHYTOPATHOLOGY 2008; 46:101-22. [PMID: 18422426 PMCID: PMC2613263 DOI: 10.1146/annurev.phyto.121107.104959] [Citation(s) in RCA: 389] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Pathogen entry into host tissue is a critical first step in causing infection. For foliar bacterial plant pathogens, natural surface openings, such as stomata, are important entry sites. Historically, these surface openings have been considered as passive portals of entry for plant pathogenic bacteria. However, recent studies have shown that stomata can play an active role in limiting bacterial invasion as part of the plant innate immune system. As a counter-defense, the plant pathogen Pseudomonas syringae pv. tomato DC3000 uses the virulence factor coronatine to actively open stomata. In nature, many foliar bacterial disease outbreaks require high humidity, rain, or storms, which could favor stomatal opening and/or bypass stomatal defense by creating wounds as alternative entry sites. Further studies on microbial and environmental regulation of stomatal closure and opening could fill gaps in our understanding of bacterial pathogenesis, disease epidemiology, and microbiology of the phyllosphere.
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Affiliation(s)
- Maeli Melotto
- Department of Biology, University of Texas at Arlington, TX, 76019, USA; e-mail: .
| | - William Underwood
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA; e-mail: .
| | - Sheng Yang He
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA; e-mail: .
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Aruscavage D, Lee K, Miller S, LeJeune J. Interactions Affecting the Proliferation and Control of Human Pathogens on Edible Plants. J Food Sci 2006. [DOI: 10.1111/j.1750-3841.2006.00157.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Schreiber L, Krimm U, Knoll D, Sayed M, Auling G, Kroppenstedt RM. Plant-microbe interactions: identification of epiphytic bacteria and their ability to alter leaf surface permeability. THE NEW PHYTOLOGIST 2005; 166:589-94. [PMID: 15819920 DOI: 10.1111/j.1469-8137.2005.01343.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Bacteria were either isolated from leaf surfaces of Hedera helix or obtained from a culture collection in order to analyse their effect on barrier properties of isolated Hedera and Prunus laurocerasus cuticles. On the basis of the 16S rDNA sequences the genera of the six bacterial isolates from Hedera were identified as Pseudomonas sp., Stenotrophomonas sp. and Achromobacter. Water permeability of cuticles isolated from H. helix was measured before and after inoculation with the six bacterial strains. In addition water permeability of cuticles isolated from P. laurocerasus was measured before and after inoculation with the three bacterial strains Pseudomonas aeruginosa, Xanthomonas campestris and Corynebacterium fascians. Rates of water diffusing across isolated cuticles of both species significantly increased by up to 50% after inoculation with all bacterial strains. Obtained results show that epiphytic bacteria have the ability of increasing water permeability of Hedera and Prunus cuticles, which in turn should increase the availability of water and dissolved compounds in the phyllopshere. Consequently, living conditions in the habitat phyllosphere are improved. It can be concluded that the ability to change leaf surface properties will improve epiphytic fitness of leaf surface bacteria.
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Affiliation(s)
- Lukas Schreiber
- Institut für Zelluläre und Molekulare Botanik, Universität Bonn, Kirschallee 1, 53115 Bonn, Germany.
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Affiliation(s)
- Steven E Lindow
- Department of Plant and Microbial Biology, University of California, Berkeley 94720, USA.
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Affiliation(s)
- Steven E Lindow
- Department of Plant and Microbial Biology, University of California, Berkeley 94720, USA.
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Haba E, Pinazo A, Jauregui O, Espuny MJ, Infante MR, Manresa A. Physicochemical characterization and antimicrobial properties of rhamnolipids produced by Pseudomonas aeruginosa 47T2 NCBIM 40044. Biotechnol Bioeng 2003; 81:316-22. [PMID: 12474254 DOI: 10.1002/bit.10474] [Citation(s) in RCA: 215] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Pseudomonas aeruginosa 47T2, grown in submerged culture with waste frying oil as a carbon source, produced a mixture of rhamnolipids with surface activity. Up to 11 rhamnolipid homologs (Rha-Rha-C(8)-C(10); Rha-C(10)-C(8)/Rha-C(8)-C(10);Rha-Rha-C(8)-C(12:1); Rha-Rha-C(10)-C(10); Rha-Rha-C(10)-C(12:1); Rha-C(10)-C(10); Rha-Rha-C(10)-C(12)/Rha-Rha-C(12)-C(10); Rha-C(10)-C(12:1)/Rha-C(12:1)-C(10); Rha-Rha-C(12:1)-C(12); Rha-Rha-C(10)-C(14:1); Rha-C(10)-C(12)/Rha-C(12)-C(10)) were isolated from cultures of P. aeruginosa 47T2 from waste frying oil and identified by HPLC-MS analysis. This article deals with the production, isolation, and chemical characterization of the rhamnolipid mixture RL(47T2). The physicochemical and biological properties of RL(47T2) as a new product were also studied. Its surface tension decreased to 32.8 mN/m; and the interfacial tension against kerosene to 1 mN/m. The critical micellar concentration for RL(47T2) was 108.8 mg/mL. The product showed excellent antimicrobial properties. Antimicrobial activity was evaluated according to the minimum inhibitory concentration (MIC), the lowest concentration of an antimicrobial agent that inhibits development of visible microbial growth. Low MIC values were found for bacteria Serratia marcescens (4 microg/mL), Enterobacter aerogenes (8 microg/mL), Klebsiella pneumoniae (0.5 microg/mL), Staphylococcus aureus and Staphylococcus epidermidis (32 microg/mL), Bacillus subtilis (16 microg/mL), and phytopathogenic fungal species: Chaetonium globosum (64 microg/mL), Penicillium funiculosum (16 microg/mL), Gliocadium virens (32 microg/mL) and Fusarium solani (75 microg/mL).
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Affiliation(s)
- E Haba
- Laboratorio de Microbiología, Facultad de Farmacía, Universidad de Barcelona, Joan XXIII s/n, E-08028 Barcelona, Spain
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Marcell LM, Beattie GA. Effect of leaf surface waxes on leaf colonization by Pantoea agglomerans and Clavibacter michiganensis. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2002; 15:1236-44. [PMID: 12481996 DOI: 10.1094/mpmi.2002.15.12.1236] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
To evaluate the influence of leaf cuticular waxes on bacterial colonization of leaves, bacterial colonization patterns were examined on four glossy maize (Zea mays L.) mutants that were altered in their cuticular wax biosynthesis. Mutant gl3 was indistinguishable from the wild-type maize in its ability to foster colonization by the two bacterial species, Pantoea agglomerans and Clavibacter michiganensis subsp. nebraskensis. In contrast, the other three mutants supported the development of populations that significantly differed in size from those on the wild type. Mutant gl5 gl20 supported smaller populations of P. agglomerans, but not C. michiganensis, while mutant gl1 supported larger populations of C. michiganensis but not P. agglomerans. Mutant gl4 supported larger populations of both bacterial species. The exceptional ability of mutant gl4 to support bacterial colonization was hypothesized to result from the lower density of the crystalline waxes on gl4 than on the wild type, because a reduced crystal density could promote capillary water movement and water trapping among the wax crystals. This hypothesis was supported by the demonstration that the mechanical introduction of gaps among the wax crystals of the wild-type leaves resulted in the establishment of larger P. agglomerans populations on the altered leaves. These results provide the first direct evidence that leaf surface waxes affect bacterial leaf colonization at various stages of colonization and in a bacterial species-dependent manner.
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Affiliation(s)
- Lise M Marcell
- Iowa State University, Department of Plant Pathology, Ames 50011-3211, USA
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Irish BM, Correll JC, Morelock TE. The Effect of Synthetic Surfactants on Disease Severity of White Rust on Spinach. PLANT DISEASE 2002; 86:791-796. [PMID: 30818579 DOI: 10.1094/pdis.2002.86.7.791] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
White rust, caused by Albugo occidentalis, is an economically important disease of spinach (Spinacia oleracea). Although cultural practices and partial host resistance are used for disease management, control strategies often rely on fungicides. An alternative approach, the use of ionic (cationic or anionic) and nonionic surfactants, was evaluated for its effect on white rust in greenhouse and field experiments. Surfactant treatments were compared with a water control and two commercial fungicides, azoxystrobin (Quadris) and 1,2,3-benzothiadiazole-7-carbothioic acid S-methyl ester (Actigard). Greenhouse plants were treated with a single surfactant application followed by inoculation with sporangia. Disease severity was rated on leaves 8 to 12 days after inoculation. Field tests were conducted in Arkansas and Texas and received three to five surfactant applications during the season. Disease severity was determined at the end of the growing season. In greenhouse and field tests, all surfactant treatments showed significant reductions in white rust severity compared with water controls. The surfactants Naiad and sodium dodecyl sulfate (SDS) were highly effective and comparable to fungicides in reducing white rust severity. In a laboratory assay, microscopic examination revealed that most of the surfactants at low concentrations caused rapid (<2 min) zoospore lysis.
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Affiliation(s)
| | | | - T E Morelock
- Professor, Department of Horticulture, University of Arkansas, Fayetteville 72701
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Jana TK, Srivastava AK, Csery K, Arora DK. Influence of growth and environmental conditions on cell surface hydrophobicity ofPseudomonas fluorescensin non-specific adhesion. Can J Microbiol 1999. [DOI: 10.1139/w99-104] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The relative cell surface hydrophobicity (CSH) of 18 soil isolates of Pseudomonas fluorescens, determined by phase exclusion, hydrophobic interaction chromatography (HIC), electrostatic interaction chromatography (ESIC), and contact angle, revealed large degrees of variability. Variation in the adhesion efficiency to Macrophomina phaseolina of the hyphae/sclerotia of these isolates was also examined. Two such isolates with maximum (32.8%; isolate 12-94) and minimum (12%; isolate 30-94) CSH were selected for further study. Early- to mid-log exponential cells of these isolates were more hydrophobic than those in stationary phase, and the CSH of these isolates was also influenced by fluctuations in temperatures and pH. Isolate 12-94 exhibited high CSH (32.3%) at 30°C, compared to lower values (28-24%) in the higher temperature range (35-40°C). Increasing concentrations of either Zn2+, Fe3+, K+, and Mg2+in the growth medium were associated with the increased CSH. Trypsin, pepsin, and proteinase K (75 to 150 μg·mL-1) reduced the CSH of isolate 12-94 cells. CSH was reduced, following exposure to DTT, SDS, Triton X-100, or Tween 80. Prolonged exposure of cells to starvation (60 days) also caused a significant decline in CSH. Several protein bands (18, 21, 23, 26 kDa) of the outer cell membrane were absent in 60-day starved cells compared to unstarved cells. In conclusion, our findings demonstrate that CSH of P. fluorescens isolates may contribute to non-specific attachment/adhesion onto M. phaseolina hyphae/sclerotia, and the efficiency of adhesion is regulated by growth and other environmental conditions. Key words: adhesion, hydrophobicity, Pseudomonas fluorescens, Macrophomina phaseolina
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Angelova B, Schmauder HP. Lipophilic compounds in biotechnology--interactions with cells and technological problems. J Biotechnol 1999; 67:13-32. [PMID: 9987845 DOI: 10.1016/s0168-1656(98)00139-4] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Lipophilic compounds are of significant importance in modern biotechnology. Centerly of interest are the biodegradation as well as the biotransformation of such lipophilic and often water-immiscible substances. Both whole cells and/or enzymes are used for these processes. It is obvious that a wide range of problems arise in an application of such complex systems consisting of biocatalysts substrate(s), product(s), water, (in some cases water-immiscible organic solvents): (i) interactions between lipophilic compounds and the membranes resulting in the change of some physiological characteristics of the living system; (ii) problems in the transport of these compounds (substrates and/or products) within the complex structured reaction systems; (iii) the problem of increasing the solubility of the lipophilic and mostly water-immiscible compounds with a minimum of inhibition effects on the processes; (iv) the presence of lipophilic components may also cause changes of the transport processes within the system (e.g. immobilized cells) resulting in changed yield or activity of the biological system. These problems are critically discussed in this review in relation to the known modes of interaction of lipophilic compounds with membranes, the bioavailability of the substrates, and the cases of steroid biotransformations. An outlook of future aspects in research, development and application of such processes is given.
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Affiliation(s)
- B Angelova
- Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
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