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Soares FS, Rangel de Souza ALS, de Souza SA, de Souza Vespoli L, Pinto VB, Matiello L, da Silva FR, Menossi M, de Souza Filho GA. Fine-Tuning of Arabidopsis thaliana Response to Endophytic Colonization by Gluconacetobacter diazotrophicus PAL5 Revealed by Transcriptomic Analysis. PLANTS (BASEL, SWITZERLAND) 2024; 13:1719. [PMID: 38999559 PMCID: PMC11244368 DOI: 10.3390/plants13131719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 06/01/2024] [Accepted: 06/16/2024] [Indexed: 07/14/2024]
Abstract
Gluconacetobacter diazotrophicus is a diazotrophic endophytic bacterium that promotes the growth and development of several plant species. However, the molecular mechanisms activated during plant response to this bacterium remain unclear. Here, we used the RNA-seq approach to understand better the effect of G. diazotrophicus PAL5 on the transcriptome of shoot and root tissues of Arabidopsis thaliana. G. diazotrophicus colonized A. thaliana roots and promoted growth, increasing leaf area and biomass. The transcriptomic analysis revealed several differentially expressed genes (DEGs) between inoculated and non-inoculated plants in the shoot and root tissues. A higher number of DEGs were up-regulated in roots compared to shoots. Genes up-regulated in both shoot and root tissues were associated with nitrogen metabolism, production of glucosinolates and flavonoids, receptor kinases, and transcription factors. In contrast, the main groups of down-regulated genes were associated with pathogenesis-related proteins and heat-shock proteins in both shoot and root tissues. Genes encoding enzymes involved in cell wall biogenesis and modification were down-regulated in shoots and up-regulated in roots. In contrast, genes associated with ROS detoxification were up-regulated in shoots and down-regulated in roots. These results highlight the fine-tuning of the transcriptional regulation of A. thaliana in response to colonization by G. diazotrophicus PAL5.
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Affiliation(s)
- Fabiano Silva Soares
- Laboratório de Biotecnologia (Unidade de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro 28013-602, Brazil
| | - Ana Lídia Soares Rangel de Souza
- Laboratório de Biotecnologia (Unidade de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro 28013-602, Brazil
| | - Suzane Ariádina de Souza
- Laboratório de Biotecnologia (Unidade de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro 28013-602, Brazil
| | - Luciano de Souza Vespoli
- Laboratório de Biotecnologia (Unidade de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro 28013-602, Brazil
| | - Vitor Batista Pinto
- Laboratório de Biologia Celular e Tecidual, UENF, Campos dos Goytacazes, Rio de Janeiro 28013-602, Brazil
| | - Lucia Matiello
- Instituto de Biologia, Departamento de Genética, Evolução, Microbiologia e Imunologia, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo 13083-970, Brazil
| | - Felipe Rodrigues da Silva
- Instituto de Biologia, Departamento de Genética, Evolução, Microbiologia e Imunologia, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo 13083-970, Brazil
- Embrapa Agricultura Digital, Campinas, São Paulo 13083-886, Brazil
| | - Marcelo Menossi
- Instituto de Biologia, Departamento de Genética, Evolução, Microbiologia e Imunologia, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo 13083-970, Brazil
| | - Gonçalo Apolinário de Souza Filho
- Laboratório de Biotecnologia (Unidade de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro 28013-602, Brazil
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Dietz BR, Olszewski NE, Barney BM. Enhanced extracellular ammonium release in the plant endophyte Gluconacetobacter diazotrophicus through genome editing. Microbiol Spectr 2024; 12:e0247823. [PMID: 38038458 PMCID: PMC10783055 DOI: 10.1128/spectrum.02478-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 10/27/2023] [Indexed: 12/02/2023] Open
Abstract
IMPORTANCE Our results demonstrate increased extracellular ammonium release in the endophyte plant growth-promoting bacterium Gluconacetobacter diazotrophicus. Strains were constructed in a manner that leaves no antibiotic markers behind, such that these strains contain no transgenes. Levels of ammonium achieved by cultures of modified G. diazotrophicus strains reached concentrations of approximately 18 mM ammonium, while wild-type G. diazotrophicus remained much lower (below 50 µM). These findings demonstrate a strong potential for further improving the biofertilizer potential of this important microbe.
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Affiliation(s)
- Benjamin R. Dietz
- Department of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul, Minnesota, USA
| | - Neil E. Olszewski
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, USA
| | - Brett M. Barney
- Department of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul, Minnesota, USA
- Biotechnology Institute, University of Minnesota, St. Paul, Minnesota, USA
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Li Y, Huang Y, Wronski T, Huang M. Diversity of bacteria associated with lichens in Mt. Yunmeng in Beijing, China. PeerJ 2023; 11:e16442. [PMID: 38025692 PMCID: PMC10676717 DOI: 10.7717/peerj.16442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 10/20/2023] [Indexed: 12/01/2023] Open
Abstract
Lichens host highly complex and diverse microbial communities, which may perform essential functions in these symbiotic micro-ecosystems. In this research, sequencing of 16S rRNA was used to investigate the bacterial communities associated with lichens of two growth forms (foliose and crustose). Results showed that Pseudomonadota, Actinomycetota and Acidobacteriota were dominant phyla in both types of lichens, while Acetobacterales and Hyphomicrobiales were the dominant orders. Alpha diversity index showed that the richness of bacteria hosted by foliose lichens was significantly higher than that hosted by crustose ones. Principal co-ordinates analysis showed a significant difference between beta diversity of the foliose lichen-associated bacterial communities and those of crustose lichen-associated ones. Gene function prediction showed most functions, annotated by the lichen-associated bacteria, to be related to metabolism, suggesting that related bacteria may provide nutrients to their hosts. Generally, our results propose that microbial communities play important roles in fixing nitrogen, providing nutrients, and controlling harmful microorganisms, and are therefore an integral and indispensable part of lichens.
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Affiliation(s)
- Yimeng Li
- Department of Life Sciences, National Natural History Museum of China, Beijing, China
| | - Yinzhi Huang
- The Experimental High School Attached to Beijing Normal University, Beijing, China
| | - Torsten Wronski
- School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Manrong Huang
- Department of Life Sciences, National Natural History Museum of China, Beijing, China
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Klarenberg IJ, Keuschnig C, Salazar A, Benning LG, Vilhelmsson O. Moss and underlying soil bacterial community structures are linked to moss functional traits. Ecosphere 2023. [DOI: 10.1002/ecs2.4447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023] Open
Affiliation(s)
- Ingeborg J. Klarenberg
- Natural Resource Sciences University of Akureyri Akureyri Iceland
- Faculty of Life and Environmental Sciences University of Iceland Reykjavík Iceland
- Department of Ecological Science Vrije Universiteit Amsterdam Amsterdam Netherlands
| | - Christoph Keuschnig
- Environmental Microbial Genomics Laboratoire Ampère, CNRS, École Centrale de Lyon Écully France
- German Research Centre for Geosciences (GFZ) Interface Geochemistry Potsdam Germany
| | - Alejandro Salazar
- Faculty of Environmental and Forest Sciences Agricultural University of Iceland Reykjavík Iceland
| | - Liane G. Benning
- German Research Centre for Geosciences (GFZ) Interface Geochemistry Potsdam Germany
- Department of Earth Sciences Free University of Berlin Berlin Germany
| | - Oddur Vilhelmsson
- Natural Resource Sciences University of Akureyri Akureyri Iceland
- BioMedical Center University of Iceland Reykjavík Iceland
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Medison RG, Tan L, Medison MB, Chiwina KE. Use of beneficial bacterial endophytes: A practical strategy to achieve sustainable agriculture. AIMS Microbiol 2022; 8:624-643. [PMID: 36694581 PMCID: PMC9834078 DOI: 10.3934/microbiol.2022040] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/30/2022] [Accepted: 12/19/2022] [Indexed: 01/04/2023] Open
Abstract
Beneficial endophytic bacteria influence their host plant to grow and resist pathogens. Despite the advantages of endophytic bacteria to their host, their application in agriculture has been low. Furthermore, many plant growers improperly use synthetic chemicals due to having no or little knowledge of the role of endophytic bacteria in plant growth, the prevention and control of pathogens and poor access to endobacterial bioproducts. These synthetic chemicals have caused soil infertility, environmental contamination, disruption to ecological cycles and the emergence of resistant pests and pathogens. There is more that needs to be done to explore alternative ways of achieving sustainable plant production while maintaining environmental health. In recent years, the use of beneficial endophytic bacteria has been noted to be a promising tool in promoting plant growth and the biocontrol of pathogens. Therefore, this review discusses the roles of endophytic bacteria in plant growth and the biocontrol of plant pathogens. Several mechanisms that endophytic bacteria use to alleviate plant biotic and abiotic stresses by helping their host plants acquire nutrients, enhance plant growth and development and suppress pathogens are explained. The review also indicates that there is a gap between research and general field applications of endophytic bacteria and suggests a need for collaborative efforts between growers at all levels. Furthermore, the presence of scientific and regulatory frameworks that promote advanced biotechnological tools and bioinoculants represents major opportunities in the applications of endophytic bacteria. The review provides a basis for future research in areas related to understanding the interactions between plants and beneficial endophytic microorganisms, especially bacteria.
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Affiliation(s)
| | - Litao Tan
- College of Agriculture, Yangtze University, Jingzhou Hubei 434025, China
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Gluconacetobacter diazotrophicus Gene Fitness during Diazotrophic Growth. Appl Environ Microbiol 2022; 88:e0124122. [PMID: 36374093 PMCID: PMC9746312 DOI: 10.1128/aem.01241-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Plant growth-promoting (PGP) bacteria are important to the development of sustainable agricultural systems. PGP microbes that fix atmospheric nitrogen (diazotrophs) could minimize the application of industrially derived fertilizers and function as a biofertilizer. The bacterium Gluconacetobacter diazotrophicus is a nitrogen-fixing PGP microbe originally discovered in association with sugarcane plants, where it functions as an endophyte. It also forms endophyte associations with a range of other agriculturally relevant crop plants. G. diazotrophicus requires microaerobic conditions for diazotrophic growth. We generated a transposon library for G. diazotrophicus and cultured the library under various growth conditions and culture medium compositions to measure fitness defects associated with individual transposon inserts (transposon insertion sequencing [Tn-seq]). Using this library, we probed more than 3,200 genes and ascertained the importance of various genes for diazotrophic growth of this microaerobic endophyte. We also identified a set of essential genes. IMPORTANCE Our results demonstrate a succinct set of genes involved in diazotrophic growth for G. diazotrophicus, with a lower degree of redundancy than what is found in other model diazotrophs. The results will serve as a valuable resource for those interested in biological nitrogen fixation and will establish a baseline data set for plant free growth, which could complement future studies related to the endophyte relationship.
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Sindhu SS, Sehrawat A, Glick BR. The involvement of organic acids in soil fertility, plant health and environment sustainability. Arch Microbiol 2022; 204:720. [DOI: 10.1007/s00203-022-03321-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/22/2022] [Accepted: 11/03/2022] [Indexed: 11/21/2022]
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Tripathi A, Pandey P, Tripathi SN, Kalra A. Perspectives and potential applications of endophytic microorganisms in cultivation of medicinal and aromatic plants. FRONTIERS IN PLANT SCIENCE 2022; 13:985429. [PMID: 36247631 PMCID: PMC9560770 DOI: 10.3389/fpls.2022.985429] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 09/07/2022] [Indexed: 06/16/2023]
Abstract
Ensuring food and nutritional security, it is crucial to use chemicals in agriculture to boost yields and protect the crops against biotic and abiotic perturbations. Conversely, excessive use of chemicals has led to many deleterious effects on the environment like pollution of soil, water, and air; loss of soil fertility; and development of pest resistance, and is now posing serious threats to biodiversity. Therefore, farming systems need to be upgraded towards the use of biological agents to retain agricultural and environmental sustainability. Plants exhibit a huge and varied niche for endophytic microorganisms inside the planta, resulting in a closer association between them. Endophytic microorganisms play pivotal roles in plant physiological and morphological characteristics, including growth promotion, survival, and fitness. Their mechanism of action includes both direct and indirect, such as mineral phosphate solubilization, fixating nitrogen, synthesis of auxins, production of siderophore, and various phytohormones. Medicinal and aromatic plants (MAPs) hold a crucial position worldwide for their valued essential oils and several phytopharmaceutically important bioactive compounds since ancient times; conversely, owing to the high demand for natural products, commercial cultivation of MAPs is on the upswing. Furthermore, the vulnerability to various pests and diseases enforces noteworthy production restraints that affect both crop yield and quality. Efforts have been made towards enhancing yields of plant crude drugs by improving crop varieties, cell cultures, transgenic plants, etc., but these are highly cost-demanding and time-consuming measures. Thus, it is essential to evolve efficient, eco-friendly, cost-effective simpler approaches for improvement in the yield and health of the plants. Harnessing endophytic microorganisms as biostimulants can be an effective and alternative step. This review summarizes the concept of endophytes, their multidimensional interaction inside the host plant, and the salient benefits associated with endophytic microorganisms in MAPs.
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Affiliation(s)
- Arpita Tripathi
- Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
- Faculty of Education, Teerthanker Mahaveer University, Moradabad, India
| | - Praveen Pandey
- Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
- Division of Plant Breeding and Genetic Resource Conservation, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Shakti Nath Tripathi
- Department of Botany, Nehru Gram Bharati Deemed to be University, Prayagraj, India
| | - Alok Kalra
- Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
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Transcriptomic Response of the Diazotrophic Bacteria Gluconacetobacter diazotrophicus Strain PAL5 to Iron Limitation and Characterization of the fur Regulatory Network. Int J Mol Sci 2022; 23:ijms23158533. [PMID: 35955667 PMCID: PMC9368920 DOI: 10.3390/ijms23158533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 07/27/2022] [Accepted: 07/28/2022] [Indexed: 01/25/2023] Open
Abstract
Gluconacetobacter diazotrophicus has been the focus of several studies aiming to understand the mechanisms behind this endophytic diazotrophic bacterium. The present study is the first global analysis of the early transcriptional response of exponentially growing G. diazotrophicus to iron, an essential cofactor for many enzymes involved in various metabolic pathways. RNA-seq, targeted gene mutagenesis and computational motif discovery tools were used to define the G. diazotrophicusfur regulon. The data analysis showed that genes encoding functions related to iron homeostasis were significantly upregulated in response to iron limitations. Certain genes involved in secondary metabolism were overexpressed under iron-limited conditions. In contrast, it was observed that the expression of genes involved in Fe-S cluster biosynthesis, flagellar biosynthesis and type IV secretion systems were downregulated in an iron-depleted culture medium. Our results support a model that controls transcription in G. diazotrophicus by fur function. The G. diazotrophicusfur protein was able to complement an E. colifur mutant. These results provide new insights into the effects of iron on the metabolism of G. diazotrophicus, as well as demonstrate the essentiality of this micronutrient for the main characteristics of plant growth promotion by G. diazotrophicus.
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Mathur V, Ulanova D. Microbial Metabolites Beneficial to Plant Hosts Across Ecosystems. MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02073-x. [PMID: 35867138 DOI: 10.1007/s00248-022-02073-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 07/05/2022] [Indexed: 06/15/2023]
Abstract
Plants are intimately connected with their associated microorganisms. Chemical interactions via natural products between plants and their microbial symbionts form an important aspect in host health and development, both in aquatic and terrestrial ecosystems. These interactions range from negative to beneficial for microbial symbionts as well as their hosts. Symbiotic microbes synchronize their metabolism with their hosts, thus suggesting a possible coevolution among them. Metabolites, synthesized from plants and microbes due to their association and coaction, supplement the already present metabolites, thus promoting plant growth, maintaining physiological status, and countering various biotic and abiotic stress factors. However, environmental changes, such as pollution and temperature variations, as well as anthropogenic-induced monoculture settings, have a significant influence on plant-associated microbial community and its interaction with the host. In this review, we put the prominent microbial metabolites participating in plant-microbe interactions in the natural terrestrial and aquatic ecosystems in a single perspective and have discussed commonalities and differences in these interactions for adaptation to surrounding environment and how environmental changes can alter the same. We also present the status and further possibilities of employing chemical interactions for environment remediation. Our review thus underlines the importance of ecosystem-driven functional adaptations of plant-microbe interactions in natural and anthropogenically influenced ecosystems and their possible applications.
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Affiliation(s)
- Vartika Mathur
- Animal Plant Interactions Lab, Department of Zoology, Sri Venkateswara College, Benito Juarez Marg, Dhaula Kuan, New Delhi-110021, India.
| | - Dana Ulanova
- Department of Marine Resource Sciences, Faculty of Agriculture and Marine Science, Kochi University, Monobe, Nankoku city, Kochi, 783-8502, Japan.
- Center for Advanced Marine Core Research, Kochi University, Monobe, Nankoku city, Kochi, 783-8502, Japan.
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Yu Y, Chen Z, Xie H, Feng X, Wang Y, Xu P. Overhauling the Effect of Surface Sterilization on Analysis of Endophytes in Tea Plants. FRONTIERS IN PLANT SCIENCE 2022; 13:849658. [PMID: 35592578 PMCID: PMC9111953 DOI: 10.3389/fpls.2022.849658] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 03/08/2022] [Indexed: 06/15/2023]
Abstract
Increasing evidence shows that plant Endophytes play a crucial role in the fitness and productivity of hosts. Surface sterilization is an indispensable process before high-throughput sequencing (HTS) and tissue separation of plant endophytes, but its potential impact on the composition and diversity of endophytes has rarely been investigated. In the present work, the influence of sodium hypochlorite (NaClO) on the diversity of endophytic bacteria and fungi in leaves and stems of tea plants was investigated. We found that the diversity of bacterial endophytes was significantly affected by the concentration of NaClO as well as the pretreatment time. Pretreatment with 0.5% NaClO for 8 min and 2.0% NaClO for 3 min were suitable for the tea plant leaves and stems, respectively, but the effects of NaClO on the diversity of fungal endophytes were limited according to the results from HTS. Regardless of NaClO sterilization, most of the endophytes in tissues, such as the dominant taxa, could not be Isolated by using the regular culture-dependent approaches. Collectively, our results demonstrated that the pretreatment with NaClO should be modified to precisely understand the diversity of endophytes from different tissues of tea plants and also indicate that more attention should be paid to establish specific culture-dependent protocols for the isolation of plant endophytes.
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Affiliation(s)
- Yueer Yu
- Institute of Tea Science, Zhejiang University, Hangzhou, China
| | - Zimeng Chen
- Institute of Tea Science, Zhejiang University, Hangzhou, China
| | - Hengtong Xie
- Institute of Tea Science, Zhejiang University, Hangzhou, China
| | - Xiaoxiao Feng
- Agricultural Experiment Station, Zhejiang University, Hangzhou, China
| | - Yuefei Wang
- Institute of Tea Science, Zhejiang University, Hangzhou, China
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou, China
| | - Ping Xu
- Institute of Tea Science, Zhejiang University, Hangzhou, China
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou, China
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Padda KP, Puri A, Nguyen NK, Philpott TJ, Chanway CP. Evaluating the rhizospheric and endophytic bacterial microbiome of pioneering pines in an aggregate mining ecosystem post-disturbance. PLANT AND SOIL 2022; 474:213-232. [PMID: 35698622 PMCID: PMC9184430 DOI: 10.1007/s11104-022-05327-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 02/02/2022] [Indexed: 06/15/2023]
Abstract
AIMS Despite little soil development and organic matter accumulation, lodgepole pine (Pinus contorta var. latifolia) consistently shows vigorous growth on bare gravel substrate of aggregate mining pits in parts of Canadian sub-boreal forests. This study aimed to investigate the bacterial microbiome of lodgepole pine trees growing at an unreclaimed gravel pit in central British Columbia and suggest their potential role in tree growth and survival following mining activity. METHODS We characterized the diversity, taxonomic composition, and relative abundance of bacterial communities in rhizosphere and endosphere niches of pine trees regenerating at the gravel pit along with comparing them with a nearby undisturbed forested site using 16S rRNA high-throughput sequencing. Additionally, the soil and plant nutrient contents at both sites were also analyzed. RESULTS Although soil N-content at the gravel pit was drastically lower than the forest site, pine tissue N-levels at both sites were identical. Beta-diversity was affected by site and niche-type, signifying that the diversity of bacterial communities harboured by pine trees was different between both sites and among various plant-niches. Bacterial alpha-diversity was comparable at both sites but differed significantly between belowground and aboveground plant-niches. In terms of composition, pine trees predominantly associated with taxa that appear plant-beneficial including phylotypes of Rhizobiaceae, Acetobacteraceae, and Beijerinckiaceae at the gravel pit and Xanthobacteraceae, Acetobacteraceae, Beijerinckiaceae and Acidobacteriaceae at the forest site. CONCLUSIONS Our results suggest that, following mining activity, regenerating pine trees recruit bacterial communities that could be plant-beneficial and support pine growth in an otherwise severely N-limited disturbed environment. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s11104-022-05327-2.
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Affiliation(s)
- Kiran Preet Padda
- Department of Forest and Conservation Sciences, Faculty of Forestry, The University of British Columbia, Vancouver, BC Canada
| | - Akshit Puri
- Present Address: School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland
- UCD Earth Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | | | - Timothy J. Philpott
- British Columbia Ministry of Forests, Lands and Natural Resource Operations, Williams Lake, BC Canada
| | - Chris P. Chanway
- Department of Forest and Conservation Sciences, Faculty of Forestry, The University of British Columbia, Vancouver, BC Canada
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Essential role of extracytoplasmic proteins in the resistance of Gluconacetobacter diazotrophicus to cadmium. Res Microbiol 2022; 173:103922. [DOI: 10.1016/j.resmic.2022.103922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 01/20/2022] [Accepted: 01/21/2022] [Indexed: 11/23/2022]
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14
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Li W, Li F, Zeng H, Ma L, Qi L, Wang X, Wang W, Peng Z, Degen AA, Bai Y, Zhang T, Huang M, Han J, Shang Z. Diversity and Variation of Asymbiotic Nitrogen-Fixing Microorganisms in Alpine Grasslands on the Tibetan Plateau. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.702848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Asymbiotic nitrogen-fixing (ANF) bacteria contribute a substantial amount of nitrogen in ecosystems, especially in those with low symbiotic nitrogen fixation (SNF) capability. Degradation of alpine grassland is widespread on the Tibetan Plateau and sown grassland has become one of the main strategies for grassland restoration. However, the diversity and community structure of ANF bacteria in different grassland types remain unknown. The aim of this study was to fill this gap. Soil samples were obtained from 39 grassland plots selected from three counties in the eastern Tibetan Plateau. The plots were classified as natural grassland (NG), sown grassland (SG), lightly degraded grassland (LDG), and severely degraded grassland (SDG). ANF microbial communities of the four grassland types were compared at the level of community and species diversity by 16S rRNA high-throughput sequencing technology. The phylum Proteobacteria accounted for >72% of the ANF bacteria. The community structures of soil ANF bacteria differed significantly (p < 0.01) among grassland types. We concluded that: (1) planting gramineous forage could possibly mitigate the decrease in diversity of soil ANF bacteria caused by grassland degradation; and (2) the diversity of soil ANF bacteria in alpine grassland of the Tibetan Plateau is closely related to grassland degradation and restoration.
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Rehman HF, Ashraf A, Muzammil S, Siddique MH, Ali T. Assessment of zinc solubilization potential of zinc-resistant Pseudomonas oleovorans strain ZSB13 isolated from contaminated soil. BRAZ J BIOL 2021; 83:e240015. [PMID: 34320047 DOI: 10.1590/1519-6984.240015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 02/01/2021] [Indexed: 11/22/2022] Open
Abstract
Zinc is an essential micronutrient that is required for optimum plant growth. It is present in soil in insoluble forms. Bacterial solubilization of soil unavailable form of Zn into available form, is an emerging approach to alleviate the Zn deficiency for plants and human beings. Zinc solubilizing bacteria (ZSB) could be a substitute for chemical Zn fertilizer. The present study aimed to isolate and characterize bacterial species from the contaminated soil and evaluate their Zn solubilizing potential. Zn resistant bacteria were isolated and evaluated for their MIC against Zn. Among the 13 isolated bacterial strains ZSB13 showed maximum MIC value upto 30mM/L. The bacterial strain with the highest resistance against Zn was selected for further analysis. Molecular characterization of ZSB13 was performed by 16S rRNA gene amplification which confirmed it as Pseudomonas oleovorans. Zn solubilization was determined through plate assay and broth medium. Four insoluble salts (zinc oxide (ZnO), zinc carbonate (ZnCO3), zinc sulphite (ZnS) and zinc phosphate (Zn3(PO4)2) were used for solubilization assay. Our results shows 11 mm clear halo zone on agar plates amended with ZnO. Likewise, ZSB13 showed significant release of Zn in broth amended with ZnCO3 (17 and 16.8 ppm) and ZnO (18.2 ppm). Furthermore, Zn resistance genes czcD was also enriched in ZSB13. In our study, bacterial strain comprising Zn solubilization potential has been isolated that could be further used for the growth enhancement of crops.
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Affiliation(s)
- H F Rehman
- Government College University, Department of, Zoology, Faisalabad, Pakistan
| | - A Ashraf
- Government College University, Department of, Zoology, Faisalabad, Pakistan
| | - S Muzammil
- Government College University, Department of Microbiology, Faisalabad, Pakistan
| | - M H Siddique
- Government College University, Department of Bioinformatics and Biotechnology, Faisalabad, Pakistan
| | - T Ali
- Government College University, Department of, Zoology, Faisalabad, Pakistan
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Root-Associated Bacterial Community Shifts in Hydroponic Lettuce Cultured with Urine-Derived Fertilizer. Microorganisms 2021; 9:microorganisms9061326. [PMID: 34207399 PMCID: PMC8233860 DOI: 10.3390/microorganisms9061326] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 06/07/2021] [Accepted: 06/15/2021] [Indexed: 12/12/2022] Open
Abstract
Recovery of nutrients from source-separated urine can truncate our dependency on synthetic fertilizers, contributing to more sustainable food production. Urine-derived fertilizers have been successfully applied in soilless cultures. However, little is known about the adaptation of the plant to the nutrient environment. This study investigated the impact of urine-derived fertilizers on plant performance and the root-associated bacterial community of hydroponically grown lettuce (Lactuca sativa L.). Shoot biomass, chlorophyll, phenolic, antioxidant, and mineral content were associated with shifts in the root-associated bacterial community structures. K-struvite, a high-performing urine-derived fertilizer, supported root-associated bacterial communities that overlapped most strongly with control NPK fertilizer. Contrarily, lettuce performed poorly with electrodialysis (ED) concentrate and hydrolyzed urine and hosted distinct root-associated bacterial communities. Comparing the identified operational taxonomic units (OTU) across the fertilizer conditions revealed strong correlations between specific bacterial genera and the plant physiological characteristics, salinity, and NO3−/NH4+ ratio. The root-associated bacterial community networks of K-struvite and NPK control fertilized plants displayed fewer nodes and node edges, suggesting that good plant growth performance does not require highly complex ecological interactions in hydroponic growth conditions.
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17
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Qu Q, Li Y, Zhang Z, Cui H, Zhao Q, Liu W, Lu T, Qian H. Effects of S-metolachlor on wheat (Triticum aestivum L.) seedling root exudates and the rhizosphere microbiome. JOURNAL OF HAZARDOUS MATERIALS 2021; 411:125137. [PMID: 33858101 DOI: 10.1016/j.jhazmat.2021.125137] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 01/09/2021] [Accepted: 01/09/2021] [Indexed: 06/12/2023]
Abstract
S-metolachlor (S-ME) is a common chloroacetanilide herbicide. Here, we investigated the effects of S-ME on wheat seedling growth and explored via metabolomics the driver through which S-ME changes the rhizosphere microbiome. The results indicated that 4 mg/kg S-ME had a strong inhibitory effect on plant growth by inducing hydrogen peroxide (H2O2) levels. The richness of the rhizosphere microbiome markedly decreased after S-ME treatment, although the abundance of some potential beneficial rhizobacteria, such as Rhizobiaceae and Burkholderiaceae, increased suggesting that plants recruited potential beneficial microorganisms to resist S-ME-induced stress. Spearman correlation analysis revealed that Rhizobiaceae and Burkholderiaceae were positively correlated with organic acids secreted by plants after S-ME treatment, implying that potential beneficial microorganisms may be attracted mainly by organic acids. Our results demonstrated the phytotoxicity of S-ME on crop growth and indicated both that S-ME could influence rhizosphere microorganism abundance and that recruitment of potential beneficial microorganisms could be the result of root exudate regulation.
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Affiliation(s)
- Qian Qu
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Yan Li
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Zhenyan Zhang
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Hengzheng Cui
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Qianqiu Zhao
- Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, PR China
| | - Wanyue Liu
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Tao Lu
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Haifeng Qian
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China; Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, PR China.
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18
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Meier DV, Imminger S, Gillor O, Woebken D. Distribution of Mixotrophy and Desiccation Survival Mechanisms across Microbial Genomes in an Arid Biological Soil Crust Community. mSystems 2021; 6:e00786-20. [PMID: 33436509 PMCID: PMC7901476 DOI: 10.1128/msystems.00786-20] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 12/08/2020] [Indexed: 02/06/2023] Open
Abstract
Desert surface soils devoid of plant cover are populated by a variety of microorganisms, many with yet unresolved physiologies and lifestyles. Nevertheless, a common feature vital for these microorganisms inhabiting arid soils is their ability to survive long drought periods and reactivate rapidly in rare incidents of rain. Chemolithotrophic processes such as oxidation of atmospheric hydrogen and carbon monoxide are suggested to be a widespread energy source to support dormancy and resuscitation in desert soil microorganisms. Here, we assessed the distribution of chemolithotrophic, phototrophic, and desiccation-related metabolic potential among microbial populations in arid biological soil crusts (BSCs) from the Negev Desert, Israel, via population-resolved metagenomic analysis. While the potential to utilize light and atmospheric hydrogen as additional energy sources was widespread, carbon monoxide oxidation was less common than expected. The ability to utilize continuously available energy sources might decrease the dependency of mixotrophic populations on organic storage compounds and carbon provided by the BSC-founding cyanobacteria. Several populations from five different phyla besides the cyanobacteria encoded CO2 fixation potential, indicating further potential independence from photoautotrophs. However, we also found population genomes with a strictly heterotrophic genetic repertoire. The highly abundant Rubrobacteraceae (Actinobacteriota) genomes showed particular specialization for this extreme habitat, different from their closest cultured relatives. Besides the ability to use light and hydrogen as energy sources, they encoded extensive O2 stress protection and unique DNA repair potential. The uncovered differences in metabolic potential between individual, co-occurring microbial populations enable predictions of their ecological niches and generation of hypotheses on the dynamics and interactions among them.IMPORTANCE This study represents a comprehensive community-wide genome-centered metagenome analysis of biological soil crust (BSC) communities in arid environments, providing insights into the distribution of genes encoding different energy generation mechanisms, as well as survival strategies, among populations in an arid soil ecosystem. It reveals the metabolic potential of several uncultured and previously unsequenced microbial genera, families, and orders, as well as differences in the metabolic potential between the most abundant BSC populations and their cultured relatives, highlighting once more the danger of inferring function on the basis of taxonomy. Assigning functional potential to individual populations allows for the generation of hypotheses on trophic interactions and activity patterns in arid soil microbial communities and represents the basis for future resuscitation and activity studies of the system, e.g., involving metatranscriptomics.
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Affiliation(s)
- Dimitri V Meier
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Stefanie Imminger
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Osnat Gillor
- Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sde Boker, Israel
| | - Dagmar Woebken
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
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19
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Leandro MR, Vespoli LDS, Andrade LF, Soares FS, Boechat AL, Pimentel VR, Moreira JR, Passamani LZ, Silveira V, de Souza Filho GA. DegP protease is essential for tolerance to salt stress in the plant growth-promoting bacterium Gluconacetobacter diazotrophicus PAL5. Microbiol Res 2020; 243:126654. [PMID: 33285429 DOI: 10.1016/j.micres.2020.126654] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 11/13/2020] [Accepted: 11/18/2020] [Indexed: 11/19/2022]
Abstract
The use of plant growth-promoting bacteria represents an alternative to the massive use of mineral fertilizers in agriculture. However, some abiotic stresses commonly found in the environment, like salinity, can affect the efficiency of this approach. Here, we investigated the key mechanisms involved in the response of the plant growth-promoting bacterium Gluconacetobacter diazotrophicus to salt stress by using morphological and cell viability analyses, comparative proteomics, and reverse genetics. Our results revealed that the bacteria produce filamentous cells in response to salt at 100 mM and 150 mM NaCl. However, such a response was not observed at higher concentrations, where cell viability was severely affected. Proteomic analysis showed that salt stress modulates proteins involved in several pathways, including iron uptake, outer membrane efflux, osmotic adjustment, cell division and elongation, and protein transport and quality control. Proteomic data also revealed the repression of several extracytoplasmic proteins, especially those located at periplasm and outer membrane. The role of such pathways in the tolerance to salt stress was analyzed by the use of mutant defectives for Δtbdr (iron uptake), ΔmtlK and ΔotsA (compatible solutes synthesis), and ΔdegP (quality control of nascent extracytoplasmic proteins). ΔdegP presented the highest sensitivity to salt stress, Δtbdr, andΔmtlK also showed increased sensitivity, but ΔotsA was not affected. This is the first demonstration that DegP protein, a protease with minor chaperone activity, is essential for tolerance to salt stress in G. diazotrophicus. Our data contribute to a better understanding of the molecular bases that control the bacterial response/tolerance to salt stress, shedding light on quality control of nascent extracytoplasmic proteins.
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Affiliation(s)
- Mariana Ramos Leandro
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte, Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego, 2000, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Luciano de Souza Vespoli
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte, Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego, 2000, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Leandro Fernandes Andrade
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte, Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego, 2000, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Fabiano Silva Soares
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte, Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego, 2000, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Ana Laura Boechat
- Instituto de Química (Departamento de Bioquímica), Universidade de São Paulo, Av. Prof. Lineu Prestes, 748, São Paulo, SP, Brazil
| | - Vivian Ribeiro Pimentel
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte, Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego, 2000, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Julia Rosa Moreira
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte, Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego, 2000, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Lucas Zanchetta Passamani
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte, Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego, 2000, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Vanildo Silveira
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte, Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego, 2000, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Gonçalo Apolinário de Souza Filho
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte, Fluminense Darcy Ribeiro (UENF), Av. Alberto Lamego, 2000, Campos dos Goytacazes, Rio de Janeiro, Brazil.
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20
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Leandro M, Andrade L, Vespoli L, Moreira J, Pimentel V, Soares F, Passamani L, Silveira V, de Souza Filho G. Comparative proteomics reveals essential mechanisms for osmotolerance in Gluconacetobacter diazotrophicus. Res Microbiol 2020; 172:103785. [PMID: 33035671 DOI: 10.1016/j.resmic.2020.09.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/24/2020] [Accepted: 09/25/2020] [Indexed: 12/17/2022]
Abstract
Plant growth-promoting bacteria are a promising alternative to improve agricultural sustainability. Gluconacetobacter diazotrophicus is an osmotolerant bacterium able to colonize several plant species, including sugarcane, coffee, and rice. Despite its biotechnological potential, the mechanisms controlling such osmotolerance remain unclear. The present study investigated the key mechanisms of resistance to osmotic stress in G. diazotrophicus. The molecular pathways regulated by the stress were investigated by comparative proteomics, and proteins essential for resistance were identified by knock-out mutagenesis. Proteomics analysis led to identify regulatory pathways for osmotic adjustment, de novo saturated fatty acids biosynthesis, and uptake of nutrients. The mutagenesis analysis showed that the lack of AccC protein, an essential component of de novo fatty acid biosynthesis, severely affected G. diazotrophicus resistance to osmotic stress. Additionally, knock-out mutants for nutrients uptake (Δtbdr and ΔoprB) and compatible solutes synthesis (ΔmtlK and ΔotsA) became more sensitive to osmotic stress. Together, our results identified specific genes and mechanisms regulated by osmotic stress in an osmotolerant bacterium, shedding light on the essential role of cell envelope and extracytoplasmic proteins for osmotolerance.
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Affiliation(s)
- Mariana Leandro
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
| | - Leandro Andrade
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
| | - Luciano Vespoli
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
| | - Julia Moreira
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
| | - Vivian Pimentel
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
| | - Fabiano Soares
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
| | - Lucas Passamani
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
| | - Vanildo Silveira
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
| | - Gonçalo de Souza Filho
- Laboratório de Biotecnologia (Setor de Biologia Integrativa), Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, Rio de Janeiro, Brazil.
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21
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Xie H, Feng X, Wang M, Wang Y, Kumar Awasthi M, Xu P. Implications of endophytic microbiota in Camellia sinensis: a review on current understanding and future insights. Bioengineered 2020; 11:1001-1015. [PMID: 32881650 PMCID: PMC8291792 DOI: 10.1080/21655979.2020.1816788] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Endophytic fungi and bacteria are the most ubiquitous and representative commensal members that have been studied so far in various higher plants. Within colonization and interaction with their host plants, endophytic microbiota are reportedly to modulate not only the host's growth but also holobiont resilience to abiotic and biotic stresses, providing a natural reservoir and a promising solution for sustainable agricultural development challenged by global climate change. Moreover, possessing the talent to produce a wide array of high-value natural products, plant endophytic microbiota also serve as an alternative way for novel drug discovery. In this review, tea, one of the world's three largest nonalcoholic beverages and a worldwide economic woody crop, was highlighted in the context of endophytic microbiota. We explore the recent studies regarding isolation approaches, distribution characteristics and diversity, and also biological functions of endophytic microbiota in Camellia sinensis (L.) O. Kuntze. Profoundly, the future insight into interaction mechanism between endophytic microbiota and tea plants will shed light on in-depth exploration of tea microbial resources.
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Affiliation(s)
- Hengtong Xie
- College of Agriculture and Biotechnology, Zhejiang University , Hangzhou, China
| | - Xiaoxiao Feng
- Agricultural Experiment Station of Zhejiang University , Hangzhou, China
| | - Mengcen Wang
- College of Agriculture and Biotechnology, Zhejiang University , Hangzhou, China.,Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture , Hangzhou, China
| | - Yuefei Wang
- College of Agriculture and Biotechnology, Zhejiang University , Hangzhou, China.,Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture , Hangzhou, China
| | - Mukesh Kumar Awasthi
- College of Natural Resources and Environment, Northwest A&F University , Yangling, China
| | - Ping Xu
- College of Agriculture and Biotechnology, Zhejiang University , Hangzhou, China.,Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture , Hangzhou, China
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22
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Jang SW, Yoou MH, Hong WJ, Kim YJ, Lee EJ, Jung KH. Re-Analysis of 16S Amplicon Sequencing Data Reveals Soil Microbial Population Shifts in Rice Fields under Drought Condition. RICE (NEW YORK, N.Y.) 2020; 13:44. [PMID: 32617714 PMCID: PMC7332601 DOI: 10.1186/s12284-020-00403-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 06/23/2020] [Indexed: 06/11/2023]
Abstract
Rice (Oryza sativa. L) has been intensively studied to ensure a stable global supply of this commodity in the face of rapid global climate change. A critical factor that decreases crop yield is drought, which has been analyzed in various ways through many researches. Microbiome-based studies of rice investigate the symbiosis between rice and bacteria, which has been proposed as a way to overcome problems caused by drought. Several rice-associated metagenomic profiles obtained under drought conditions have been reported since the advent of next generation sequencing (NGS) technology. To elucidate the future diversity of plants and microorganisms and to promote sustainable agriculture, we reanalyzed 64 of the publicly available 16S amplicon sequencing data produced under drought condition. In the process of integrating data sets, however, we found an inconsistency that serves as a bottleneck for microbiome-based sustainability research. While this report provides clues about the composition of the microbiome under the drought conditions, the results are affected by differences in the location of the experiments, sampling conditions, and analysis protocols. Re-analysis of amplicon sequencing data of the soil microbiome in rice fields suggests that microbial composition shifts in response to drought condition and the presence of plants. Among the bacteria involved, the phylum Proteobacteria appears to play the most important role in the survival of rice under drought condition.
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Affiliation(s)
- Seok-Won Jang
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, South Korea
- Graduate School of Biotechnology, Kyung Hee University, Yongin, 17104, South Korea
| | - Myeong-Hyun Yoou
- Graduate School of Biotechnology & Crop Biotech Institute, Kyung Hee University, Yongin, 17104, South Korea
| | - Woo-Jong Hong
- Graduate School of Biotechnology & Crop Biotech Institute, Kyung Hee University, Yongin, 17104, South Korea
| | - Yeon-Ju Kim
- Department of Oriental Medicine Biotechnology, College of Life Sciences, Kyung Hee University, Yongin, 17104, South Korea
| | - Eun-Jin Lee
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, South Korea.
| | - Ki-Hong Jung
- Graduate School of Biotechnology & Crop Biotech Institute, Kyung Hee University, Yongin, 17104, South Korea.
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23
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Bledsoe RB, Goodwillie C, Peralta AL. Long-Term Nutrient Enrichment of an Oligotroph-Dominated Wetland Increases Bacterial Diversity in Bulk Soils and Plant Rhizospheres. mSphere 2020; 5:e00035-20. [PMID: 32434837 PMCID: PMC7380569 DOI: 10.1128/msphere.00035-20] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 05/07/2020] [Indexed: 12/04/2022] Open
Abstract
In nutrient-limited conditions, plants rely on rhizosphere microbial members to facilitate nutrient acquisition, and in return, plants provide carbon resources to these root-associated microorganisms. However, atmospheric nutrient deposition can affect plant-microbe relationships by changing soil bacterial composition and by reducing cooperation between microbial taxa and plants. To examine how long-term nutrient addition shapes rhizosphere community composition, we compared traits associated with bacterial (fast-growing copiotrophs, slow-growing oligotrophs) and plant (C3 forb, C4 grass) communities residing in a nutrient-poor wetland ecosystem. Results revealed that oligotrophic taxa dominated soil bacterial communities and that fertilization increased the presence of oligotrophs in bulk and rhizosphere communities. Additionally, bacterial species diversity was greatest in fertilized soils, particularly in bulk soils. Nutrient enrichment (fertilized versus unfertilized) and plant association (bulk versus rhizosphere) determined bacterial community composition; bacterial community structure associated with plant functional group (grass versus forb) was similar within treatments but differed between fertilization treatments. The core forb microbiome consisted of 602 unique taxa, and the core grass microbiome consisted of 372 unique taxa. Forb rhizospheres were enriched in potentially disease-suppressive bacterial taxa, and grass rhizospheres were enriched in bacterial taxa associated with complex carbon decomposition. Results from this study demonstrate that fertilization serves as a strong environmental filter on the soil microbiome, which leads to distinct rhizosphere communities and can shift plant effects on the rhizosphere microbiome. These taxonomic shifts within plant rhizospheres could have implications for plant health and ecosystem functions associated with carbon and nitrogen cycling.IMPORTANCE Over the last century, humans have substantially altered nitrogen and phosphorus cycling. Use of synthetic fertilizer and burning of fossil fuels and biomass have increased nitrogen and phosphorus deposition, which results in unintended fertilization of historically low-nutrient ecosystems. With increased nutrient availability, plant biodiversity is expected to decline, and the abundance of copiotrophic taxa is anticipated to increase in bacterial communities. Here, we address how bacterial communities associated with different plant functional types (forb, grass) shift due to long-term nutrient enrichment. Unlike other studies, results revealed an increase in bacterial diversity, particularly of oligotrophic bacteria in fertilized plots. We observed that nutrient addition strongly determines forb and grass rhizosphere composition, which could indicate different metabolic preferences in the bacterial communities. This study highlights how long-term fertilization of oligotroph-dominated wetlands could alter diversity and metabolism of rhizosphere bacterial communities in unexpected ways.
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Affiliation(s)
- Regina B Bledsoe
- Department of Biology, East Carolina University, Greenville, North Carolina, USA
| | - Carol Goodwillie
- Department of Biology, East Carolina University, Greenville, North Carolina, USA
| | - Ariane L Peralta
- Department of Biology, East Carolina University, Greenville, North Carolina, USA
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24
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Noh HJ, Lee YM, Park CH, Lee HK, Cho JC, Hong SG. Microbiome in Cladonia squamosa Is Vertically Stratified According to Microclimatic Conditions. Front Microbiol 2020; 11:268. [PMID: 32161575 PMCID: PMC7053493 DOI: 10.3389/fmicb.2020.00268] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 02/05/2020] [Indexed: 11/21/2022] Open
Abstract
Lichens are miniature ecosystems that contain fungi, microalgae, and bacteria. It is generally accepted that symbiosis between mycobiont and photobiont and microbial contribution to the ecosystem support the wide distribution of lichens in terrestrial ecosystems, including polar areas. The composition of symbiotic components can be affected by subtle microenvironmental differences within a thallus, as well as large-scale climate differences. In this study, we investigated fine-scale profiles of algal, fungal, and bacterial compositions through horizontal and vertical positions of the Antarctic lichen Cladonia squamosa colonies by next-generation sequencing of the nuclear large subunit rRNA gene (nucLSU) of eukaryotes and the 16S rRNA gene of bacteria. Apical parts of thalli were exposed to strong light, low moisture, and high variability of temperature compared with basal parts. Microbial diversity increased from apical parts to basal parts of thalli. Asterochloris erici was the major photobiont in apical positions of thalli, but other microalgal operational taxonomic units (OTUs) of Trebouxiophyceae and Ulvophyceae were major microalgal components in basal positions. Photochemical responses of algal components from apical and basal parts of thalli were quite different under variable temperature and humidity conditions. Several fungal OTUs that belonged to Arthoniomycetes and Lecanoromycetes, and diverse bacterial OTUs that belonged to Alphaproteobacteria, Acidobacteria_Gp1, and candidate division WPS-2 showed a clear distribution pattern according to their vertical positions within thalli. The overall lichen microbiome was significantly differentiated by the vertical position within a thallus. These results imply that different microclimate are formed at different lichen thallus parts, which can affect microbial compositions and physiological responses according to positions within the thalli.
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Affiliation(s)
- Hyun-Ju Noh
- Division of Polar Life Sciences, Korea Polar Research Institute, Incheon, South Korea
- Department of Biological Sciences, Inha University, Incheon, South Korea
| | - Yung Mi Lee
- Division of Polar Life Sciences, Korea Polar Research Institute, Incheon, South Korea
| | - Chae Haeng Park
- Division of Polar Life Sciences, Korea Polar Research Institute, Incheon, South Korea
| | - Hong Kum Lee
- Division of Polar Life Sciences, Korea Polar Research Institute, Incheon, South Korea
| | - Jang-Cheon Cho
- Department of Biological Sciences, Inha University, Incheon, South Korea
| | - Soon Gyu Hong
- Division of Polar Life Sciences, Korea Polar Research Institute, Incheon, South Korea
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25
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Ramírez-Nava EJ, Ortega-Cuellar D, González-Valdez A, Castillo-Rodríguez RA, Ponce-Soto GY, Hernández-Ochoa B, Cárdenas-Rodríguez N, Martínez-Rosas V, Morales-Luna L, Serrano-Posada H, Sierra-Palacios E, Arreguin-Espinosa R, Cuevas-Cruz M, Rocha-Ramírez LM, Pérez de la Cruz V, Marcial-Quino J, Gómez-Manzo S. Molecular Cloning and Exploration of the Biochemical and Functional Analysis of Recombinant Glucose-6-Phosphate Dehydrogenase from Gluconoacetobacter diazotrophicus PAL5. Int J Mol Sci 2019; 20:ijms20215279. [PMID: 31652968 PMCID: PMC6862599 DOI: 10.3390/ijms20215279] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/21/2019] [Accepted: 10/22/2019] [Indexed: 11/17/2022] Open
Abstract
Gluconacetobacter diazotrophicus PAL5 (GDI) is an endophytic bacterium with potential biotechnological applications in industry and agronomy. The recent description of its complete genome and its principal metabolic enzymes suggests that glucose metabolism is accomplished through the pentose phosphate pathway (PPP); however, the enzymes participating in this pathway have not yet been characterized in detail. The objective of the present work was to clone, purify, and biochemically and physicochemically characterize glucose-6-phosphate dehydrogenase (G6PD) from GDI. The gene was cloned and expressed as a tagged protein in E. coli to be purified by affinity chromatography. The native state of the G6PD protein in the solution was found to be a tetramer with optimal activity at pH 8.8 and a temperature between 37 and 50 °C. The apparent Km values for G6P and nicotinamide adenine dinucleotide phosphate (NADP+) were 63 and 7.2 μM, respectively. Finally, from the amino acid sequence a three-dimensional (3D) model was obtained, which allowed the arrangement of the amino acids involved in the catalytic activity, which are conserved (RIDHYLGKE, GxGGDLT, and EKPxG) with those of other species, to be identified. This characterization of the enzyme could help to identify new environmental conditions for the knowledge of the plant–microorganism interactions and a better use of GDI in new technological applications.
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Affiliation(s)
- Edson Jiovany Ramírez-Nava
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México 04530, Mexico.
| | - Daniel Ortega-Cuellar
- Laboratorio de Nutrición Experimental, Instituto Nacional de Pediatría, Secretaría de Salud 04530, Mexico.
| | - Abigail González-Valdez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico.
| | - Rosa Angélica Castillo-Rodríguez
- Consejo Nacional de Ciencia y Tecnología (CONACYT), Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de Mexico 04530, Mexico.
| | - Gabriel Yaxal Ponce-Soto
- Institute for Bio- and Geosciences (IBG-2: Plant Sciences), Forschungszentrum Jülich, Wilhelm Johnen Straße, 52428 Jülich, Germany.
| | - Beatriz Hernández-Ochoa
- Laboratorio de Inmunoquímica, Hospital Infantil de México Federico Gómez, Secretaría de Salud, Ciudad de Mexico 06720, Mexico.
| | - Noemí Cárdenas-Rodríguez
- Laboratorio de Neurociencias, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México 04530, Mexico.
| | - Víctor Martínez-Rosas
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México 04530, Mexico.
| | - Laura Morales-Luna
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México 04530, Mexico.
| | - Hugo Serrano-Posada
- Consejo Nacional de Ciencia y Tecnología (CONACYT), Laboratorio de Agrobiotecnología, Tecnoparque CLQ, Universidad de Colima, Carretera los Limones-Loma de Juárez, Colima 28629, Mexico.
| | - Edgar Sierra-Palacios
- Colegio de Ciencias y Humanidades, Plantel Casa Libertad, Universidad Autónoma de la Ciudad de México, Ciudad de Mexico 09620, Mexico.
| | - Roberto Arreguin-Espinosa
- Departamento de Química de Biomacromoléculas, Instituto de Química, Universidad Nacional Autónoma de Mexico, Ciudad de Mexico 04510, Mexico.
| | - Miguel Cuevas-Cruz
- Departamento de Química de Biomacromoléculas, Instituto de Química, Universidad Nacional Autónoma de Mexico, Ciudad de Mexico 04510, Mexico.
| | - Luz María Rocha-Ramírez
- Departamento de Infectología, Hospital Infantil de México Federico Gómez, Dr. Márquez No. 162, Col Doctores, Delegación Cuauhtémoc 06720, Mexico.
| | - Verónica Pérez de la Cruz
- Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, S.S.A., Ciudad de Mexico 14269, Mexico.
| | - Jaime Marcial-Quino
- Consejo Nacional de Ciencia y Tecnología (CONACYT), Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de Mexico 04530, Mexico.
| | - Saúl Gómez-Manzo
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México 04530, Mexico.
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Jakob F, Quintero Y, Musacchio A, Estrada‐de los Santos P, Hernández L, Vogel RF. Acetic acid bacteria encode two levansucrase types of different ecological relationship. Environ Microbiol 2019; 21:4151-4165. [DOI: 10.1111/1462-2920.14768] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/24/2019] [Accepted: 07/31/2019] [Indexed: 01/10/2023]
Affiliation(s)
- Frank Jakob
- Lehrstuhl für Technische Mikrobiologie, Technische Universität München Gregor‐Mendel‐Straße 4, 85354 Freising Germany
| | - Yamira Quintero
- Grupo Tecnología de Enzimas, Centro de Ingeniería Genética y Biotecnología (CIGB) Ave 31 entre 158 y 190, Apartado Postal 6162, Habana 10600 Cuba
| | - Alexis Musacchio
- Departamento de Biología de Sistemas Centro de Ingeniería Genética y Biotecnología (CIGB) Ave 31 entre 158 y 190, Apartado Postal 6162, Habana 10600 Cuba
| | - Paulina Estrada‐de los Santos
- Instituto Politécnico Nacional, Escuela Nacional de Ciencias Biológicas, Prol. de Carpio y Plan de Ayala s/n Col. Santo Tomás C.P., 11340 Cd. de México Mexico
| | - Lázaro Hernández
- Grupo Tecnología de Enzimas, Centro de Ingeniería Genética y Biotecnología (CIGB) Ave 31 entre 158 y 190, Apartado Postal 6162, Habana 10600 Cuba
| | - Rudi F. Vogel
- Lehrstuhl für Technische Mikrobiologie, Technische Universität München Gregor‐Mendel‐Straße 4, 85354 Freising Germany
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Ullah A, Nisar M, Ali H, Hazrat A, Hayat K, Keerio AA, Ihsan M, Laiq M, Ullah S, Fahad S, Khan A, Khan AH, Akbar A, Yang X. Drought tolerance improvement in plants: an endophytic bacterial approach. Appl Microbiol Biotechnol 2019; 103:7385-7397. [PMID: 31375881 DOI: 10.1007/s00253-019-10045-4] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 07/17/2019] [Accepted: 07/23/2019] [Indexed: 12/31/2022]
Abstract
Climate change is a crucial issue among the serious emerging problems which got a global attention in the last few decades. With the climate change, worldwide crop production has been seriously affected by drought stress. In this regard, various technologies including traditional breeding and genetic engineering are used to cope with drought stress. However, the interactions between plants and endophytic bacteria emerged as an interesting era of knowledge that can be used for novel agriculture practices. Endophytic bacteria which survive within plant tissues are among the most appropriate technologies improving plant growth and yield under drought conditions. These endophytic bacteria live within plant tissues and release various phytochemicals that assist plant to withstand in harsh environmental conditions, i.e., drought stress. Their plant growth-promoting characteristics include nitrogen fixation, phosphate solubilization, mineral uptake, and the production of siderophore, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, and various phytohormones. These plant growth promoting characteristics of endophytic bacteria improve root length and density, which lead to the enhance drought tolerance. In addition, plant-endophytic bacteria assist plant to withstand against drought stress by producing drought-tolerant substances, for instance, abscisic acid, indole-3-acetic acid, ACC deaminase, and various volatile compounds. Indirectly, endophytic bacteria also improve osmotic adjustment, relative water content, and antioxidant activity of inoculated plants. Altogether, these bacterial-mediated drought tolerance and plant growth-promoting processes continue even under severe drought conditions which lead to enhanced plant growth promotion and yield. The present review highlights a natural and environment-friendly strategy in the form of drought-tolerant and plant growth-promoting endophytic bacteria to improve drought tolerance in plants.
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Affiliation(s)
- Abid Ullah
- Department of Botany, University of Malakand, Chakdara Dir Lower, Khyber Pakhtunkhwa, 18800, Pakistan. .,National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China.
| | - Mohammad Nisar
- Department of Botany, University of Malakand, Chakdara Dir Lower, Khyber Pakhtunkhwa, 18800, Pakistan
| | - Hazrat Ali
- Department of Zoology, University of Malakand, Chakdara Dir Lower, Khyber Pakhtunkhwa, 18800, Pakistan
| | - Ali Hazrat
- Department of Botany, University of Malakand, Chakdara Dir Lower, Khyber Pakhtunkhwa, 18800, Pakistan
| | - Kashif Hayat
- Key Laboratory of Urban Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Ayaz Ali Keerio
- Department of Plant Breeding and Genetics, Faculty of Crop Production, Sindh Agriculture University, Tando Jam, Hyderabad, Sindh, Pakistan
| | - Muhammad Ihsan
- Department of Botany, University of Malakand, Chakdara Dir Lower, Khyber Pakhtunkhwa, 18800, Pakistan
| | - Muhammad Laiq
- Department of Botany, University of Malakand, Chakdara Dir Lower, Khyber Pakhtunkhwa, 18800, Pakistan
| | - Sana Ullah
- Department of Botany, University of Malakand, Chakdara Dir Lower, Khyber Pakhtunkhwa, 18800, Pakistan
| | - Shah Fahad
- Department of Agriculture, University of Swabi, Swabi, Khyber Pakhtunkhwa, Pakistan
| | - Aziz Khan
- Key Laboratory of Plant Genetic and Breeding, College of Agriculture, Guanxi University, Nanning, 530005, Guanxi, China
| | - Aamir Hamid Khan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China
| | - Adnan Akbar
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China
| | - Xiyan Yang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China
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Chun SJ, Cui Y, Lee CS, Cho AR, Baek K, Choi A, Ko SR, Lee HG, Hwang S, Oh HM, Ahn CY. Characterization of Distinct CyanoHABs-Related Modules in Microbial Recurrent Association Network. Front Microbiol 2019; 10:1637. [PMID: 31379787 PMCID: PMC6650593 DOI: 10.3389/fmicb.2019.01637] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 07/02/2019] [Indexed: 12/22/2022] Open
Abstract
To elucidate the interspecies connectivity between cyanobacteria and other bacteria (non-cyanobacteria) during cyanobacterial harmful algal blooms (cyanoHABs), samples were collected from the Nakdong River, Korea, from June 2016 to August 2017, and microbial recurrent association network (MRAN) analysis was performed to overcome the limitations of conventional network analysis. Microcystis blooms were tightly linked with Pseudanabaena in summer and were accompanied by significant changes in the non-cyanobacterial community composition (nCCC) compared to non-bloom period. Riverine bacterial communities could be clearly separated into modules that were involved in the formation, maintenance, and decomposition of cyanoHABs. Roseomonas and Herbaspirillum were directly linked with major cyanobacteria and assigned to connector and module hub in cyanoHABs-related modules, respectively. The functional profiles of the cyanoHABs-related modules suggested that nitrate reduction, aerobic ammonia oxidation, fermentation, and hydrocarbon degradation could be increased during the Microcystis bloom periods. In conclusion, MRAN analysis revealed that specific bacteria belonging to cyanoHABs-related module, including connectors and module hubs, appeared to contribute to the development and collapse of cyanoHABs. Therefore, to understand cyanoHABs, a modular microbial perspective may be more helpful than a single bacterial species perspective.
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Affiliation(s)
- Seong-Jun Chun
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea.,Department of Environmental Biotechnology, KRIBB School of Biotechnology - Korea University of Science and Technology (UST), Daejeon, South Korea
| | - Yingshun Cui
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea
| | - Chang Soo Lee
- Division of Freshwater Bioresources Research, Nakdonggang National Institute of Biological Resources, Sangju, South Korea
| | - A Ra Cho
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea
| | - Kiwoon Baek
- Division of Freshwater Bioresources Research, Nakdonggang National Institute of Biological Resources, Sangju, South Korea
| | - Ahyoung Choi
- Division of Freshwater Bioresources Culture Research, Nakdonggang National Institute of Biological Resources, Sangju, South Korea
| | - So-Ra Ko
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea
| | - Hyung-Gwan Lee
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea
| | - Seungwoo Hwang
- Korean Bioinformation Center (KOBIC), Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea
| | - Hee-Mock Oh
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea.,Department of Environmental Biotechnology, KRIBB School of Biotechnology - Korea University of Science and Technology (UST), Daejeon, South Korea
| | - Chi-Yong Ahn
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, South Korea.,Department of Environmental Biotechnology, KRIBB School of Biotechnology - Korea University of Science and Technology (UST), Daejeon, South Korea
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Akyol TY, Niwa R, Hirakawa H, Maruyama H, Sato T, Suzuki T, Fukunaga A, Sato T, Yoshida S, Tawaraya K, Saito M, Ezawa T, Sato S. Impact of Introduction of Arbuscular Mycorrhizal Fungi on the Root Microbial Community in Agricultural Fields. Microbes Environ 2019; 34:23-32. [PMID: 30584188 PMCID: PMC6440726 DOI: 10.1264/jsme2.me18109] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 10/22/2018] [Indexed: 12/22/2022] Open
Abstract
Arbuscular mycorrhizal (AM) fungi are important members of the root microbiome and may be used as biofertilizers for sustainable agriculture. To elucidate the impact of AM fungal inoculation on indigenous root microbial communities, we used high-throughput sequencing and an analytical pipeline providing fixed operational taxonomic units (OTUs) as an output to investigate the bacterial and fungal communities of roots treated with a commercial AM fungal inoculum in six agricultural fields. AM fungal inoculation significantly influenced the root microbial community structure in all fields. Inoculation changed the abundance of indigenous AM fungi and other fungal members in a field-dependent manner. Inoculation consistently enriched several bacterial OTUs by changing the abundance of indigenous bacteria and introducing new bacteria. Some inoculum-associated bacteria closely interacted with the introduced AM fungi, some of which belonged to the genera Burkholderia, Cellulomonas, Microbacterium, Sphingomonas, and Streptomyces and may be candidate mycorrhizospheric bacteria that contribute to the establishment and/or function of the introduced AM fungi. Inoculated AM fungi also co-occurred with several indigenous bacteria with putative beneficial traits, suggesting that inoculated AM fungi may recruit specific taxa to confer better plant performance. The bacterial families Methylobacteriaceae, Acetobacteraceae, Armatimonadaceae, and Alicyclobacillaceae were consistently reduced by the inoculation, possibly due to changes in the host plant status caused by the inoculum. To the best of our knowledge, this is the first large-scale study to investigate interactions between AM fungal inoculation and indigenous root microbial communities in agricultural fields.
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Affiliation(s)
| | - Rieko Niwa
- Central Region Agricultural Research Center, National Agriculture and Food Research Organization (NARO)2–1–18 Kannondai, Tsukuba 305–8666Japan
| | | | - Hayato Maruyama
- Graduate School of Agriculture, Hokkaido UniversitySapporo 060–8589Japan
| | - Takumi Sato
- Faculty of Agriculture, Yamagata UniversityTsuruoka 997–8555Japan
| | - Takae Suzuki
- Field Science Center, Graduate School of Agriculture, Tohoku UniversityOsaki 989–6711Japan
| | - Ayako Fukunaga
- Western Region Agricultural Research Center, NAROAyabe 623–0035Japan
| | - Takashi Sato
- Faculty of Bioresource Sciences, Akita Prefectural UniversityAkita 010–0195Japan
| | - Shigenobu Yoshida
- Central Region Agricultural Research Center, National Agriculture and Food Research Organization (NARO)2–1–18 Kannondai, Tsukuba 305–8666Japan
| | - Keitaro Tawaraya
- Faculty of Agriculture, Yamagata UniversityTsuruoka 997–8555Japan
| | - Masanori Saito
- Field Science Center, Graduate School of Agriculture, Tohoku UniversityOsaki 989–6711Japan
- Department of Innovation Research, Japan Science and Technology AgencyTokyo, 102–0076Japan
| | - Tatsuhiro Ezawa
- Graduate School of Agriculture, Hokkaido UniversitySapporo 060–8589Japan
| | - Shusei Sato
- Graduate School of Life Sciences, Tohoku UniversitySendai 980–8577Japan
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Dent D. Non-nodular Endophytic Bacterial Symbiosis and the Nitrogen Fixation of Gluconacetobacter diazotrophicus. Symbiosis 2018. [DOI: 10.5772/intechopen.75813] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Luo Y, Wu Y, Wang H, Xing R, Zheng Z, Qiu J, Yang L. Bacterial community structure and diversity responses to the direct revegetation of an artisanal zinc smelting slag after 5 years. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018. [PMID: 29541981 DOI: 10.1007/s11356-018-1573-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
This comparative field study examined the responses of bacterial community structure and diversity to the revegetation of zinc (Zn) smelting waste slag with eight plant species after 5 years. The microbial community structure of waste slag with and without vegetation was evaluated using high-throughput sequencing. The physiochemical properties of Zn smelting slag after revegetation with eight plant rhizospheres for 5 years were improved compared to those of bulk slag. Revegetation significantly increased the microbial community diversity in plant rhizospheres, and at the phylum level, Proteobacteria, Acidobacteria, and Bacteroidetes were notably more abundant in rhizosphere slags than those in bulk waste slag. Additionally, revegetation increased the relative abundance of plant growth-promoting rhizobacteria such as Flavobacterium, Streptomyces, and Arthrobacter as well as symbiotic N2 fixers such as Bradyrhizobium. Three dominant native plant species (Arundo donax, Broussonetia papyrifera, and Robinia pseudoacacia) greatly increased the quality of the rhizosphere slags. Canonical correspondence analysis showed that the differences in bacterial community structure between the bulk and rhizosphere slags were explained by slag properties, i.e., pH, available copper (Cu) and lead (Pb), moisture, available nitrogen (N), phosphorus (P), and potassium (K), and organic matter (OM); however, available Zn and cadmium (Cd) contents were the slag parameters that best explained the differences between the rhizosphere communities of the eight plant species. The results suggested that revegetation plays an important role in enhancing bacterial community abundance and diversity in rhizosphere slags and that revegetation may also regulate microbiological properties and diversity mainly through changes in heavy metal bioavailability and physiochemical slag characteristics.
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Affiliation(s)
- Youfa Luo
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Yonggui Wu
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China.
- Institute of Applied Ecology, Guizhou University, Guiyang, 550025, China.
| | - Hu Wang
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Rongrong Xing
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Zhilin Zheng
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Jing Qiu
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Lian Yang
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China
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Conformationally Gated Electron Transfer in Nitrogenase. Isolation, Purification, and Characterization of Nitrogenase From Gluconacetobacter diazotrophicus. Methods Enzymol 2017. [PMID: 29746246 DOI: 10.1016/bs.mie.2017.09.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
Nitrogenase is a complex, bacterial enzyme that catalyzes the ATP-dependent reduction of dinitrogen (N2) to ammonia (NH3). In its most prevalent form, it consists of two proteins, the catalytic molybdenum-iron protein (MoFeP) and its specific reductase, the iron protein (FeP). A defining feature of nitrogenase is that electron and proton transfer processes linked to substrate reduction are synchronized by conformational changes driven by ATP-dependent FeP-MoFeP interactions. Yet, despite extensive crystallographic, spectroscopic, and biochemical information on nitrogenase, the structural basis of the ATP-dependent synchronization mechanism is not understood in detail. In this chapter, we summarize some of our efforts toward obtaining such an understanding. Experimental investigations of the structure-function relationships in nitrogenase are challenged by the fact that it cannot be readily expressed heterologously in nondiazotrophic bacteria, and the purification protocols for nitrogenase are only known for a small number of diazotrophic organisms. Here, we present methods for purifying and characterizing nitrogenase from a new model organism, Gluconacetobacter diazotrophicus. We also describe procedures for observing redox-dependent conformational changes in G. diazotrophicus nitrogenase by X-ray crystallography and electron paramagnetic resonance spectroscopy, which have provided new insights into the redox-dependent conformational gating processes in nitrogenase.
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The persistence and performance of phosphate-solubilizing Gluconacetobacter liquefaciens qzr14 in a cucumber soil. 3 Biotech 2017; 7:294. [PMID: 28868221 DOI: 10.1007/s13205-017-0926-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 08/22/2017] [Indexed: 10/19/2022] Open
Abstract
The persistence and performance of plant growth-promoting microorganisms (PGPMs) in soil are considered critical features for effectiveness, yet they are poorly understood. Here, we investigated the colonization and activity of a new PGPM, phosphate-solubilizing Gluconacetobacter liquefaciens qzr14, in a pot culture experiment using cucumber as test crop for 20 days. The number of G. liquefaciens and bacterial diversity in the rhizosphere and bulk soil were monitored by real-time PCR and DGGE, respectively. Soil phosphorus and cucumber biomass were also examined. G. liquefaciens qzr14 effectively colonized the rhizosphere soil (bacterial density ranging from 2.70 × 108 to 1.18 × 109 copies per gram dry soil). G. liquefaciens qzr14 inoculation had significantly positive effects on bacterial diversity (BD) of the rhizosphere and bulk soil and the ratio of soluble phosphorus to total phosphorus (SP/TP). The number of G. liquefaciens in the rhizosphere soil was significantly related to SP/TP and the BD of the rhizosphere and bulk soil. BD in rhizosphere soil was significantly related to SP/TP and BD in bulk soil. Based on the results of correlation analysis, we inferred that the introduced G. liquefaciens qzr14 effectively colonized the rhizosphere of cucumber, and then expanded its bacterial community by solubilizing soil phosphorus. The expanded bacterial communities might promote cucumber growth by some new functions.
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Qi Z, Dong D, Yang H, Xia X. Improving fermented quality of cider vinegar via rational nutrient feeding strategy. Food Chem 2017; 224:312-319. [DOI: 10.1016/j.foodchem.2016.12.078] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 12/19/2016] [Accepted: 12/20/2016] [Indexed: 11/28/2022]
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35
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Fei H, Abudureheman A, Vessey JK. Improving a “Generation 1.5” biofuel feedstock crop: Colonization and growth enhancement of energy beet (Beta vulgare L. Beta 5833R) by inoculation with Gluconacetobacter spp. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2017. [DOI: 10.1016/j.bcab.2017.03.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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36
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Liu H, Carvalhais LC, Crawford M, Singh E, Dennis PG, Pieterse CMJ, Schenk PM. Inner Plant Values: Diversity, Colonization and Benefits from Endophytic Bacteria. Front Microbiol 2017. [PMID: 29312235 DOI: 10.1016/j.apsoil.2011.09.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
One of the most exciting scientific advances in recent decades has been the realization that the diverse and immensely active microbial communities are not only 'passengers' with plants, but instead play an important role in plant growth, development and resistance to biotic and abiotic stresses. A picture is emerging where plant roots act as 'gatekeepers' to screen soil bacteria from the rhizosphere and rhizoplane. This typically results in root endophytic microbiome dominated by Proteobacteria, Actinobacteria and to a lesser extent Bacteroidetes and Firmicutes, but Acidobacteria and Gemmatimonadetes being almost depleted. A synthesis of available data suggest that motility, plant cell-wall degradation ability and reactive oxygen species scavenging seem to be crucial traits for successful endophytic colonization and establishment of bacteria. Recent studies provide solid evidence that these bacteria serve host functions such as improving of plant nutrients through acquisition of nutrients from soil and nitrogen fixation in leaves. Additionally, some endophytes can engage 'priming' plants which elicit a faster and stronger plant defense once pathogens attack. Due to these plant growth-promoting effects, endophytic bacteria are being widely explored for their use in the improvement of crop performance. Updating the insights into the mechanism of endophytic bacterial colonization and interactions with plants is an important step in potentially manipulating endophytic bacteria/microbiome for viable strategies to improve agricultural production.
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Affiliation(s)
- Hongwei Liu
- School of Agriculture and Food Sciences, The University of Queensland, Brisbane, QLD, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Lilia C Carvalhais
- Centre for Horticultural Science, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, QLD, Australia
| | - Mark Crawford
- Department of Natural Resources and Mines, Toowoomba, QLD, Australia
| | - Eugenie Singh
- School of Agriculture and Food Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Paul G Dennis
- School of Earth and Environmental Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Corné M J Pieterse
- Plant-Microbe Interactions, Institute of Environmental Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Peer M Schenk
- School of Agriculture and Food Sciences, The University of Queensland, Brisbane, QLD, Australia
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Rodrigues EP, Soares CDP, Galvão PG, Imada EL, Simões-Araújo JL, Rouws LFM, de Oliveira ALM, Vidal MS, Baldani JI. Identification of Genes Involved in Indole-3-Acetic Acid Biosynthesis by Gluconacetobacter diazotrophicus PAL5 Strain Using Transposon Mutagenesis. Front Microbiol 2016; 7:1572. [PMID: 27774087 PMCID: PMC5053998 DOI: 10.3389/fmicb.2016.01572] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 09/20/2016] [Indexed: 02/03/2023] Open
Abstract
Gluconacetobacter diazotrophicus is a beneficial nitrogen-fixing endophyte found in association with sugarcane plants and other important crops. Beneficial effects of G. diazotrophicus on sugarcane growth and productivity have been attributed to biological nitrogen fixation process and production of phytohormones especially indole-3-acetic acid (IAA); however, information about the biosynthesis and function of IAA in G. diazotrophicus is still scarce. Therefore, the aim of this work was to identify genes and pathways involved in IAA biosynthesis in this bacterium. In our study, the screening of two independent Tn5 mutant libraries of PAL5T strain using the Salkowski colorimetric assay revealed two mutants (Gdiaa34 and Gdiaa01), which exhibited 95% less indolic compounds than the parental strain when grown in LGIP medium supplemented with L-tryptophan. HPLC chromatograms of the wild-type strain revealed the presence of IAA and of the biosynthetic intermediates indole-3-pyruvic acid (IPyA) and indole-3-lactate (ILA). In contrast, the HPLC profiles of both mutants showed no IAA but only a large peak of non-metabolized tryptophan and low levels of IPyA and ILA were detected. Molecular characterization revealed that Gdiaa01 and Gdiaa34 mutants had unique Tn5 insertions at different sites within the GDI2456 open read frame, which is predicted to encode a L-amino acid oxidase (LAAO). GDI2456 (lao gene) forms a cluster with GDI2455 and GDI2454 ORFs, which are predicted to encode a cytochrome C and an RidA protein, respectively. RT-qPCR showed that transcript levels of lao. cccA, and ridA genes were reduced in the Gdiaa01 as compared to PAL5T. In addition, rice plants inoculated with Gdiaa01 showed significantly smaller root development (length, surface area, number of forks and tips) than those plants inoculated with PAL5T. In conclusion, our study demonstrated that G. diazotrophicus PAL5T produces IAA via the IPyA pathway in cultures supplemented with tryptophan and provides evidence for the involvement of an L-amino acid oxidase gene cluster in the biosynthesis of IAA. Furthermore, we showed that the mutant strains with reduction in IAA biosynthesis ability, in consequence of the lower transcription levels of genes of the lao cluster, had remarkable effects on development of rice roots.
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Affiliation(s)
- Elisete P Rodrigues
- Laboratório de Genética de Microrganismos, Departamento de Biologia, Universidade Estadual de Londrina Londrina, Brazil
| | | | | | - Eddie L Imada
- Laboratório de Genética de Microrganismos, Departamento de Biologia, Universidade Estadual de Londrina Londrina, Brazil
| | | | | | - André L M de Oliveira
- Laboratório de Bioquímica Molecular, Departamento de Bioquímica e Biotecnologia, Universidade Estadual de Londrina Londrina, Brazil
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Carrell AA, Carper DL, Frank AC. Subalpine conifers in different geographical locations host highly similar foliar bacterial endophyte communities. FEMS Microbiol Ecol 2016; 92:fiw124. [DOI: 10.1093/femsec/fiw124] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2016] [Indexed: 12/14/2022] Open
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Moyes AB, Kueppers LM, Pett-Ridge J, Carper DL, Vandehey N, O'Neil J, Frank AC. Evidence for foliar endophytic nitrogen fixation in a widely distributed subalpine conifer. THE NEW PHYTOLOGIST 2016; 210:657-68. [PMID: 27000956 DOI: 10.1111/nph.13850] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 12/06/2015] [Indexed: 05/22/2023]
Abstract
Coniferous forest nitrogen (N) budgets indicate unknown sources of N. A consistent association between limber pine (Pinus flexilis) and potential N2 -fixing acetic acid bacteria (AAB) indicates that native foliar endophytes may supply subalpine forests with N. To assess whether the P. flexilis-AAB association is consistent across years, we re-sampled P. flexilis twigs at Niwot Ridge, CO and characterized needle endophyte communities via 16S rRNA Illumina sequencing. To investigate whether endophytes have access to foliar N2 , we incubated twigs with (13) N2 -enriched air and imaged radioisotope distribution in needles, the first experiment of its kind using (13) N. We used the acetylene reduction assay to test for nitrogenase activity within P. flexilis twigs four times from June to September. We found evidence for N2 fixation in P. flexilis foliage. N2 diffused readily into needles and nitrogenase activity was positive across sampling dates. We estimate that this association could provide 6.8-13.6 μg N m(-2) d(-1) to P. flexilis stands. AAB dominated the P. flexilis needle endophyte community. We propose that foliar endophytes represent a low-cost, evolutionarily stable N2 -fixing strategy for long-lived conifers. This novel source of biological N2 fixation has fundamental implications for understanding forest N budgets.
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Affiliation(s)
- Andrew B Moyes
- Sierra Nevada Research Institute, University of California Merced, 5200 N. Lake Road, Merced, CA, 95343, USA
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Lara M Kueppers
- Sierra Nevada Research Institute, University of California Merced, 5200 N. Lake Road, Merced, CA, 95343, USA
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Jennifer Pett-Ridge
- Physical and Life Sciences Directorate, Lawrence Livermore National Lab, 7000 East Avenue, Livermore, CA, 94550, USA
| | - Dana L Carper
- Life and Environmental Sciences, School of Natural Sciences, University of California Merced, 5200 N. Lake Road, Merced, CA, 95343, USA
| | - Nick Vandehey
- Molecular Biophysics and Integrated Bioimaging Division, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - James O'Neil
- Molecular Biophysics and Integrated Bioimaging Division, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - A Carolin Frank
- Sierra Nevada Research Institute, University of California Merced, 5200 N. Lake Road, Merced, CA, 95343, USA
- Life and Environmental Sciences, School of Natural Sciences, University of California Merced, 5200 N. Lake Road, Merced, CA, 95343, USA
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De Oliveira MVV, Intorne AC, Vespoli LDS, Madureira HC, Leandro MR, Pereira TNS, Olivares FL, Berbert-Molina MA, De Souza Filho GA. Differential effects of salinity and osmotic stress on the plant growth-promoting bacterium Gluconacetobacter diazotrophicus PAL5. Arch Microbiol 2016; 198:287-94. [PMID: 26809283 DOI: 10.1007/s00203-015-1176-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 11/26/2015] [Accepted: 12/07/2015] [Indexed: 10/22/2022]
Abstract
Plant growth-promoting bacteria (PGPB) represent a promising alternative to the massive use of industrial fertilizers in agriculture. Gluconacetobacter diazotrophicus is a PGPB that colonizes several plant species. Although this bacterium is able to grow at high sucrose concentrations, its response to environmental stresses is poorly understood. The present study evaluated G. diazotrophicus PAL5 response to stresses caused by sucrose, PEG 400, NaCl, KCl, Na2SO4 and K2SO4. Morphological, ultrastructural and cell growth analysis revealed that G. diazotrophicus PAL5 is more sensitive to salt than osmotic stress. Growth inhibition and strong morphological changes were caused by salinity, in consequence of Cl ion-specific toxic effect. Interestingly, low osmotic stress levels were beneficial for bacterial multiplication, which was able to tolerate high sucrose concentrations, Na2SO4 and K2SO4. Our data show that G. diazotrophicus PAL5 has differential response to osmotic and salinity stress, which may influence its use as inoculant in saline environments.
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Affiliation(s)
- Marcos Vinicius V De Oliveira
- Laboratory of Biotechnology, Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF (State University of Northern Rio de Janeiro - UENF), Campos dos Goytacazes, RJ, 28013-600, Brazil
| | - Aline C Intorne
- Laboratory of Biotechnology, Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF (State University of Northern Rio de Janeiro - UENF), Campos dos Goytacazes, RJ, 28013-600, Brazil
| | - Luciano de S Vespoli
- Laboratory of Biotechnology, Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF (State University of Northern Rio de Janeiro - UENF), Campos dos Goytacazes, RJ, 28013-600, Brazil
| | - Hérika C Madureira
- Laboratory of Genetics and Plant Breeding, Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF (State University of Northern Rio de Janeiro - UENF), Campos dos Goytacazes, RJ, Brazil
| | - Mariana R Leandro
- Laboratory of Biotechnology, Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF (State University of Northern Rio de Janeiro - UENF), Campos dos Goytacazes, RJ, 28013-600, Brazil
| | - Telma N S Pereira
- Laboratory of Genetics and Plant Breeding, Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF (State University of Northern Rio de Janeiro - UENF), Campos dos Goytacazes, RJ, Brazil
| | - Fábio L Olivares
- Laboratory of Cell and Tissue Biology, Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF (State University of Northern Rio de Janeiro - UENF), Campos dos Goytacazes, RJ, Brazil
| | - Marília A Berbert-Molina
- Laboratory of Biotechnology, Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF (State University of Northern Rio de Janeiro - UENF), Campos dos Goytacazes, RJ, 28013-600, Brazil
| | - Gonçalo A De Souza Filho
- Laboratory of Biotechnology, Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF (State University of Northern Rio de Janeiro - UENF), Campos dos Goytacazes, RJ, 28013-600, Brazil.
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Rodríguez-Andrade O, Fuentes-Ramírez LE, Morales-García YE, Molina-Romero D, Bustillos-Cristales MR, Martínez-Contreras RD, Muñoz-Rojas J. The decrease in the population of Gluconacetobacter diazotrophicus in sugarcane after nitrogen fertilization is related to plant physiology in split root experiments. Rev Argent Microbiol 2015; 47:335-43. [PMID: 26652262 DOI: 10.1016/j.ram.2015.09.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 09/23/2015] [Accepted: 09/29/2015] [Indexed: 10/22/2022] Open
Abstract
It has been established that a decrease in the population of Gluconacetobacter diazotrophicus associated with sugarcane occurs after nitrogen fertilization. This fact could be due to a direct influence of NH(4)NO(3) on bacterial cells or to changes in plant physiology after fertilizer addition, affecting bacterial establishment. In this work, we observed that survival of G. diazotrophicus was directly influenced when 44.8mM of NH(4)NO(3) (640mgN/plant) was used for in vitro experiments. Furthermore, micropropagated sugarcane plantlets were inoculated with G. diazotrophicus and used for split root experiments, in which both ends of the system were fertilized with a basal level of NH(4)NO(3) (0.35mM; 10mgN/plant). Twenty days post inoculation (dpi) one half of the plants were fertilized with a high dose of NH(4)NO(3) (6.3mM; 180 mgN/plant) on one end of the system. This nitrogen level was lower than that directly affecting G. diazotrophicus cells; however, it caused a decrease in the bacterial population in comparison with control plants fertilized with basal nitrogen levels. The decrease in the population of G. diazotrophicus was higher in pots fertilized with a basal nitrogen level when compared with the corresponding end supplied with high levels of NH4NO3 (100dpi; 80 days post fertilization) of the same plant system. These observations suggest that the high nitrogen level added to the plants induce systemic physiological changes that affect the establishment of G. diazotrophicus.
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Affiliation(s)
- Osvaldo Rodríguez-Andrade
- Laboratorio Ecología Molecular Microbiana, Centro de Investigaciones en Ciencias Microbiológicas (CICM)-Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, México
| | - Luis E Fuentes-Ramírez
- Laboratorio Ecología Molecular Microbiana, Centro de Investigaciones en Ciencias Microbiológicas (CICM)-Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, México
| | - Yolanda E Morales-García
- Laboratorio Ecología Molecular Microbiana, Centro de Investigaciones en Ciencias Microbiológicas (CICM)-Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, México
| | - Dalia Molina-Romero
- Laboratorio Ecología Molecular Microbiana, Centro de Investigaciones en Ciencias Microbiológicas (CICM)-Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, México
| | - María R Bustillos-Cristales
- Laboratorio Ecología Molecular Microbiana, Centro de Investigaciones en Ciencias Microbiológicas (CICM)-Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, México
| | - Rebeca D Martínez-Contreras
- Laboratorio Ecología Molecular Microbiana, Centro de Investigaciones en Ciencias Microbiológicas (CICM)-Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, México
| | - Jesús Muñoz-Rojas
- Laboratorio Ecología Molecular Microbiana, Centro de Investigaciones en Ciencias Microbiológicas (CICM)-Instituto de Ciencias (IC), Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, México.
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Reis VM, Teixeira KRDS. Nitrogen fixing bacteria in the family Acetobacteraceae and their role in agriculture. J Basic Microbiol 2015; 55:931-49. [PMID: 25736602 PMCID: PMC7166518 DOI: 10.1002/jobm.201400898] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 01/27/2015] [Indexed: 11/17/2022]
Abstract
For centuries, the Acetobacteraceae is known as a family that harbors many species of organisms of biotechnological importance for industry. Nonetheless, since 1988 representatives of this family have also been described as nitrogen fixing bacteria able to plant growth promotion by a variety of mechanisms. Nitrogen fixation is a biological process that guarantees that the atmospheric N2 is incorporated into organic matter by several bacterial groups. Most representatives of this group, also known as diazotrophic, are generally associated with soil rhizosphere of many plants and also establishing a more specific association living inside roots, leaves, and others plants tissues as endophyte. Their roles as plant growth-promoting microorganisms are generally related to increase in plant biomass, phosphate and other mineral solubilization, and plant pathogen control. Here, we report many of these plant growth-promoting processes related to nitrogen fixing species already described in Acetobacteraceae family, especially Gluconacetobacter diazotrophicus and their importance to agriculture. In addition, a brief review of the state of art of the phylogenetics, main physiological and biochemical characteristics, molecular and functional genomic data of this group of Acetobacteraceae is presented.
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van Zyl LJ, Schubert WD, Tuffin MI, Cowan DA. Structure and functional characterization of pyruvate decarboxylase from Gluconacetobacter diazotrophicus. BMC STRUCTURAL BIOLOGY 2014; 14:21. [PMID: 25369873 PMCID: PMC4428508 DOI: 10.1186/s12900-014-0021-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 09/25/2014] [Indexed: 11/10/2022]
Abstract
BACKGROUND Bacterial pyruvate decarboxylases (PDC) are rare. Their role in ethanol production and in bacterially mediated ethanologenic processes has, however, ensured a continued and growing interest. PDCs from Zymomonas mobilis (ZmPDC), Zymobacter palmae (ZpPDC) and Sarcina ventriculi (SvPDC) have been characterized and ZmPDC has been produced successfully in a range of heterologous hosts. PDCs from the Acetobacteraceae and their role in metabolism have not been characterized to the same extent. Examples include Gluconobacter oxydans (GoPDC), G. diazotrophicus (GdPDC) and Acetobacter pasteutrianus (ApPDC). All of these organisms are of commercial importance. RESULTS This study reports the kinetic characterization and the crystal structure of a PDC from Gluconacetobacter diazotrophicus (GdPDC). Enzyme kinetic analysis indicates a high affinity for pyruvate (K M 0.06 mM at pH 5), high catalytic efficiencies (1.3 • 10(6) M(-1) • s(-1) at pH 5), pHopt of 5.5 and Topt at 45°C. The enzyme is not thermostable (T½ of 18 minutes at 60°C) and the calculated number of bonds between monomers and dimers do not give clear indications for the relatively lower thermostability compared to other PDCs. The structure is highly similar to those described for Z. mobilis (ZmPDC) and A. pasteurianus PDC (ApPDC) with a rmsd value of 0.57 Å for Cα when comparing GdPDC to that of ApPDC. Indole-3-pyruvate does not serve as a substrate for the enzyme. Structural differences occur in two loci, involving the regions Thr341 to Thr352 and Asn499 to Asp503. CONCLUSIONS This is the first study of the PDC from G. diazotrophicus (PAL5) and lays the groundwork for future research into its role in this endosymbiont. The crystal structure of GdPDC indicates the enzyme to be evolutionarily closely related to homologues from Z. mobilis and A. pasteurianus and suggests strong selective pressure to keep the enzyme characteristics in a narrow range. The pH optimum together with reduced thermostability likely reflect the host organisms niche and conditions under which these properties have been naturally selected for. The lack of activity on indole-3-pyruvate excludes this decarboxylase as the enzyme responsible for indole acetic acid production in G. diazotrophicus.
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Affiliation(s)
- Leonardo J van Zyl
- Institute for Microbial Biotechnology and Metagenomics (IMBM), University of the Western Cape, Robert Sobukwe Road, Bellville, Cape Town, South Africa.
| | - Wolf-Dieter Schubert
- Department of Biochemistry, University of Pretoria, 2 Lynnwood Road, Pretoria, 0002, South Africa.
| | - Marla I Tuffin
- Institute for Microbial Biotechnology and Metagenomics (IMBM), University of the Western Cape, Robert Sobukwe Road, Bellville, Cape Town, South Africa.
| | - Don A Cowan
- Department of Genetics, University of Pretoria, Pretoria, 0002, South Africa.
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Gluconic acid produced by Gluconacetobacter diazotrophicus Pal5 possesses antimicrobial properties. Res Microbiol 2014; 165:549-58. [DOI: 10.1016/j.resmic.2014.06.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 06/12/2014] [Accepted: 06/17/2014] [Indexed: 11/22/2022]
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Gomes DF, da Silva Batista JS, Rolla AAP, da Silva LP, Bloch C, Galli-Terasawa LV, Hungria M. Proteomic analysis of free-living Bradyrhizobium diazoefficiens: highlighting potential determinants of a successful symbiosis. BMC Genomics 2014; 15:643. [PMID: 25086822 PMCID: PMC4287336 DOI: 10.1186/1471-2164-15-643] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 07/25/2014] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Strain CPAC 7 (=SEMIA 5080) was recently reclassified into the new species Bradyrhizobium diazoefficiens; due to its outstanding efficiency in fixing nitrogen, it has been used in commercial inoculants for application to crops of soybean [Glycine max (L.) Merr.] in Brazil and other South American countries. Although the efficiency of B. diazoefficiens inoculant strains is well recognized, few data on their protein expression are available. RESULTS We provided a two-dimensional proteomic reference map of CPAC 7 obtained under free-living conditions, with the successful identification of 115 spots, representing 95 different proteins. The results highlighted the expression of molecular determinants potentially related to symbiosis establishment (e.g. inositol monophosphatase, IMPase), fixation of atmospheric nitrogen (N2) (e.g. NifH) and defenses against stresses (e.g. chaperones). By using bioinformatic tools, it was possible to attribute probable functions to ten hypothetical proteins. For another ten proteins classified as "NO related COG" group, we analyzed by RT-qPCR the relative expression of their coding-genes in response to the nodulation-gene inducer genistein. Six of these genes were up-regulated, including blr0227, which may be related to polyhydroxybutyrate (PHB) biosynthesis and competitiveness for nodulation. CONCLUSIONS The proteomic map contributed to the identification of several proteins of B. diazoefficiens under free-living conditions and our approach-combining bioinformatics and gene-expression assays-resulted in new information about unknown genes that might play important roles in the establishment of the symbiosis with soybean.
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Affiliation(s)
| | | | | | | | | | | | - Mariangela Hungria
- Embrapa Soja, Embrapa Soja, C,P, 231, 86001-970 Londrina, Paraná, Brazil.
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Gluconacetobacter diazotrophicus PAL5 possesses an active quorum sensing regulatory system. Antonie van Leeuwenhoek 2014; 106:497-506. [PMID: 24974195 DOI: 10.1007/s10482-014-0218-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 06/13/2014] [Indexed: 10/25/2022]
Abstract
The endophytic bacterium Gluconacetobacter diazotrophicus colonizes a broad range of host plants. Its plant growth-promoting capability is related to the capacity to perform biological nitrogen fixation, the biosynthesis of siderophores, antimicrobial substances and the solubilization of mineral nutrients. Colonization of and survival in these endophytic niche requires a complex regulatory network. Among these, quorum sensing systems (QS) are signaling mechanisms involved in the control of several genes related to microbial interactions, host colonization and stress survival. G. diazotrophicus PAL5 possesses a QS composed of a luxR and a luxI homolog, and produces eight molecules from the AHL family as QS signals. In this report data are provided showing that glucose concentration modifies the relative levels of these signal molecules. The activity of G. diazotrophicus PAL5 QS is also altered in presence of other carbon sources and under saline stress conditions. Inactivation of the QS system of G. diazotrophicus PAL5 by means of a quorum quenching strategy allowed the identification of extracellular and intracellular proteins under the control of this regulatory mechanism.
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Madhaiyan M, Peng N, Te NS, Hsin I C, Lin C, Lin F, Reddy C, Yan H, Ji L. Improvement of plant growth and seed yield in Jatropha curcas by a novel nitrogen-fixing root associated Enterobacter species. BIOTECHNOLOGY FOR BIOFUELS 2013; 6:140. [PMID: 24083555 PMCID: PMC3879406 DOI: 10.1186/1754-6834-6-140] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 09/26/2013] [Indexed: 05/13/2023]
Abstract
BACKGROUND Jatropha curcas L. is an oil seed producing non-leguminous tropical shrub that has good potential to be a fuel plant that can be cultivated on marginal land. Due to the low nutrient content of the targeted plantation area, the requirement for fertilizer is expected to be higher than other plants. This factor severely affects the commercial viability of J. curcas. RESULTS We explored the feasibility to use endophytic nitrogen-fixing bacteria that are native to J. curcas to improve plant growth, biomass and seed productivity. We demonstrated that a novel N-fixing endophyte, Enterobacter sp. R4-368, was able to colonize in root and stem tissues and significantly promoted early plant growth and seed productivity of J. curcas in sterilized and non-sterilized soil. Inoculation of young seedling led to an approximately 57.2% increase in seedling vigour over a six week period. At 90 days after planting, inoculated plants showed an average increase of 25.3%, 77.7%, 27.5%, 45.8% in plant height, leaf number, chlorophyll content and stem volume, respectively. Notably, inoculation of the strain led to a 49.0% increase in the average seed number per plant and 20% increase in the average single seed weight when plants were maintained for 1.5 years in non-sterilized soil in pots in the open air. Enterobacter sp. R4-368 cells were able to colonize root tissues and moved systemically to stem tissues. However, no bacteria were found in leaves. Promotion of plant growth and leaf nitrogen content by the strain was partially lost in nifH, nifD, nifK knockout mutants, suggesting the presence of other growth promoting factors that are associated with this bacterium strain. CONCLUSION Our results showed that Enterobacter sp. R4-368 significantly promoted growth and seed yield of J. curcas. The application of the strains is likely to significantly improve the commercial viability of J. curcas due to the reduced fertilizer cost and improved oil yield.
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Affiliation(s)
- Munusamy Madhaiyan
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore
| | - Ni Peng
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore
| | - Ngoh Si Te
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore
| | - Cheng Hsin I
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore
| | - Cai Lin
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore
| | - Fu Lin
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore
| | - Chalapathy Reddy
- Joil Pte Ltd, 1 Research Link National University of Singapore, Singapore 117604, Republic of Singapore
| | - Hong Yan
- Joil Pte Ltd, 1 Research Link National University of Singapore, Singapore 117604, Republic of Singapore
| | - Lianghui Ji
- Biomaterials and Biocatalysts Group, Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Republic of Singapore
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Singh D, Sharma A, Saini GK. Biochemical and molecular characterisation of the bacterial endophytes from native sugarcane varieties of Himalayan region. 3 Biotech 2013; 3:205-212. [PMID: 28324369 PMCID: PMC3646109 DOI: 10.1007/s13205-012-0084-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 08/10/2012] [Indexed: 11/24/2022] Open
Abstract
Seven endophytic bacterial isolates were finally recovered from native sugarcane varieties at hilly areas namely Berinag, Champawat and Didihat of Uttarakhand state in northern Himalayan region. New isolates and two standard cultures—Azospirillum brasilense and Gluconacetobacter diazotrophicus, were evaluated for their morphological, biochemical and molecular characteristics. Morphologically all were rod shaped, Gram-negative bacteria. Their plant growth promotory properties were also assessed which proved isolates RtBn and StBn as IAA producing. Except isolate StBn, all were phosphate solubilising and except RtBn all produced siderophores. Molecular characterisation of the isolates was performed using amplified 16S r-DNA restriction analysis. Similarity index in unweighted pair group method with arithmetic mean programme clustered the isolates according to their geographical distribution. Native isolates showed insignificant similarity with South American strains used as standards. nifH amplification was observed with all the isolates used in the study which again establish them as potential N-fixers.
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Affiliation(s)
- Digar Singh
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Anita Sharma
- Department of Microbiology, G.B. Pant University of Agriculture and Technology, Pantnagar, 263145, Uttaranchal, India
| | - Gurvinder Kaur Saini
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
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Urzúa LS, Vázquez-Candanedo AP, Sánchez-Espíndola A, Ramírez CÁ, Baca BE. Identification and characterization of an iron ABC transporter operon in Gluconacetobacter diazotrophicus Pal 5. Arch Microbiol 2013; 195:431-8. [PMID: 23624722 DOI: 10.1007/s00203-013-0890-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Revised: 02/02/2013] [Accepted: 02/25/2013] [Indexed: 12/01/2022]
Abstract
Gluconacetobacter diazotrophicus is a nitrogen-fixing bacterium and endophyte of sugarcane. We have cloned and sequenced the genes coding for the components of the iron ABC-type acquisition system of G. diazotrophicus. Sequence analysis revealed three ORFs, (feuA, feuB, and feuC) organized as an operon and encoding polypeptides of 346 (38 kDa), 342 (34.2 kDa), and 240 (26 kDa) amino acids, respectively. The deduced translation products of the feu operon showed similarity with a periplasmic solute-binding protein (FeuA), permease (FeuB), and ATPase (FeuC) involved in Fe transport. The role of FeuB in the survival of G. diazotrophicus under iron depletion was evaluated by comparing the ability of wild-type and FeuB-Km(R) -mutant strains in a medium without iron supplementation and in a medium containing 2, 2'-dipyridyl (DP). Growth of the mutant was affected in the medium containing DP. The operon was expressed at higher levels in cells depleted for iron than in those that contained the metal. A decrease in nitrogenase activity was observed with the FeuB-Km(R) -mutant strain that with the wild-type under iron deficiency conditions, suggesting that the Feu operon play role in Fe nutrition of G. diazotrophicus.
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Affiliation(s)
- Lucia Soto Urzúa
- Instituto de Ciencias, Centro de Investigaciones Microbiológicas, Benemérita Universidad Autónoma de Puebla, Apdo. Postal 1622, Puebla, Puebla, Mexico
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SymGRASS: a database of sugarcane orthologous genes involved in arbuscular mycorrhiza and root nodule symbiosis. BMC Bioinformatics 2013; 14 Suppl 1:S2. [PMID: 23368899 PMCID: PMC3548678 DOI: 10.1186/1471-2105-14-s1-s2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND The rationale for gathering information from plants procuring nitrogen through symbiotic interactions controlled by a common genetic program for a sustainable biofuel production is the high energy demanding application of synthetic nitrogen fertilizers. We curated sequence information publicly available for the biofuel plant sugarcane, performed an analysis of the common SYM pathway known to control symbiosis in other plants, and provide results, sequences and literature links as an online database. METHODS Sugarcane sequences and informations were downloaded from the nucEST database, cleaned and trimmed with seqclean, assembled with TGICL plus translating mapping method, and annotated. The annotation is based on BLAST searches against a local formatted plant Uniprot90 generated with CD-HIT for functional assignment, rpsBLAST to CDD database for conserved domain analysis, and BLAST search to sorghum's for Gene Ontology (GO) assignment. Gene expression was normalized according the Unigene standard, presented as ESTs/100 kb. Protein sequences known in the SYM pathway were used as queries to search the SymGRASS sequence database. Additionally, antimicrobial peptides described in the PhytAMP database served as queries to retrieve and generate expression profiles of these defense genes in the libraries compared to the libraries obtained under symbiotic interactions. RESULTS We describe the SymGRASS, a database of sugarcane orthologous genes involved in arbuscular mycorrhiza (AM) and root nodule (RN) symbiosis. The database aggregates knowledge about sequences, tissues, organ, developmental stages and experimental conditions, and provides annotation and level of gene expression for sugarcane transcripts and SYM orthologous genes in sugarcane through a web interface. Several candidate genes were found for all nodes in the pathway, and interestingly a set of symbiosis specific genes was found. CONCLUSIONS The knowledge integrated in SymGRASS may guide studies on molecular, cellular and physiological mechanisms by which sugarcane controls the establishment and efficiency of endophytic associations. We believe that the candidate sequences for the SYM pathway together with the pool of exclusively expressed tentative consensus (TC) sequences are crucial for the design of molecular studies to unravel the mechanisms controlling the establishment of symbioses in sugarcane, ultimately serving as a basis for the improvement of grass crops.
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