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Wang B, Chen C, Xiao Y, He Y, Gao Y, Kang Z, Wei X, Deng Y, Feng S, Zhou G. Geographically associated endophytic fungi contribute to the tropane alkaloids accumulation of Anisodus tanguticus. FRONTIERS IN PLANT SCIENCE 2023; 14:1297546. [PMID: 38098791 PMCID: PMC10720625 DOI: 10.3389/fpls.2023.1297546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 11/14/2023] [Indexed: 12/17/2023]
Abstract
Anisodus tanguticus is a valuable plant for extracting tropane alkaloids. However, the mechanisms by which plant microbiome mediate the accumulation of tropane alkaloids in Anisodus tanguticus are still not well understood. In this study, we collected 55 wild Anisodus tanguticus populations on the Tibetan Plateau and the tropane alkaloids content, and root-related bacteria and fungi diversity were analyzed using HPLC and 16 s rDNA and ITS sequencing. The results showed that tropane alkaloids content has obvious geographical distribution characteristics. Anisodine content had a significant positive correlation with latitude, while anisodamine and atropine content had a significant negative correlation with latitude. Variation partition analysis (VPA) showed that root endophytes play a significant role in promoting tropane alkaloid production in Anisodus tanguticus roots. The root endophytes alone explained 14% of the variation, which was the largest contributor. Soil properties variables could independently explain 5% of the variation, and climate variables could explain 1% of the variation. Of these, endophytic fungi alone accounted for 11%, while bacteria explained only 5%. Random forests and Mantel test showed that different regionally enriched endophytic fungi have a greater impact on the accumulation of tropane alkaloids than the whole endophytic fungi. Richness and relative abundance of enriched endophytic fungi in Hengduan-Qilian Mountains (HQ) group has a significant positive correlation with anisodine content, while richness and relative abundance of enriched endophytic fungi in Himalayas-Hengduan Mountains (HH) group has a significant positive correlation with anisodamine and atropine content. And, these enriched endophytic fungi have high network connectivity and distributed in separate network modules. This study further confirmed that endophytes were closely related to tropane alkaloids accumulation in Anisodus tanguticus and contribute to promote sustainable development, cultivation, and precision medicine of Anisodus tanguticus.
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Affiliation(s)
- Bo Wang
- CAS Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Xining, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chen Chen
- CAS Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Xining, China
| | - Yuanming Xiao
- CAS Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Xining, China
| | - Yan He
- Datong Beichuan Heyuan District National Nature Reserve, Xining, China
| | - Ying Gao
- Datong Beichuan Heyuan District National Nature Reserve, Xining, China
| | - Zongxiu Kang
- Datong Beichuan Heyuan District National Nature Reserve, Xining, China
| | - Xiaoxuan Wei
- Datong Beichuan Heyuan District National Nature Reserve, Xining, China
| | - Yujie Deng
- Datong Beichuan Heyuan District National Nature Reserve, Xining, China
| | - Shihong Feng
- Chengdu Tianxianzi agricultural science and technology development Co., LTD, Chengdu, China
| | - Guoying Zhou
- CAS Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Xining, China
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Kumari P, Deepa N, Trivedi PK, Singh BK, Srivastava V, Singh A. Plants and endophytes interaction: a "secret wedlock" for sustainable biosynthesis of pharmaceutically important secondary metabolites. Microb Cell Fact 2023; 22:226. [PMID: 37925404 PMCID: PMC10625306 DOI: 10.1186/s12934-023-02234-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 10/19/2023] [Indexed: 11/06/2023] Open
Abstract
Many plants possess immense pharmacological properties because of the presence of various therapeutic bioactive secondary metabolites that are of great importance in many pharmaceutical industries. Therefore, to strike a balance between meeting industry demands and conserving natural habitats, medicinal plants are being cultivated on a large scale. However, to enhance the yield and simultaneously manage the various pest infestations, agrochemicals are being routinely used that have a detrimental impact on the whole ecosystem, ranging from biodiversity loss to water pollution, soil degradation, nutrient imbalance and enormous health hazards to both consumers and agricultural workers. To address the challenges, biological eco-friendly alternatives are being looked upon with high hopes where endophytes pitch in as key players due to their tight association with the host plants. The intricate interplay between plants and endophytic microorganisms has emerged as a captivating subject of scientific investigation, with profound implications for the sustainable biosynthesis of pharmaceutically important secondary metabolites. This review delves into the hidden world of the "secret wedlock" between plants and endophytes, elucidating their multifaceted interactions that underpin the synthesis of bioactive compounds with medicinal significance in their plant hosts. Here, we briefly review endophytic diversity association with medicinal plants and highlight the potential role of core endomicrobiome. We also propose that successful implementation of in situ microbiome manipulation through high-end techniques can pave the way towards a more sustainable and pharmaceutically enriched future.
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Affiliation(s)
- Poonam Kumari
- Division of Crop Production and Protection, Central Institute of Medicinal and Aromatic Plants, Lucknow, 226015, India
| | - Nikky Deepa
- Division of Crop Production and Protection, Central Institute of Medicinal and Aromatic Plants, Lucknow, 226015, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Prabodh Kumar Trivedi
- Division of Plant Biotechnology, Central Institute of Medicinal and Aromatic Plants, Lucknow, 226015, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Brajesh K Singh
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2753, Australia
- Global Centre for Land-Based Innovation, Western Sydney University, Penrith, NSW, 2751, Australia
| | - Vaibhav Srivastava
- Division of Glycoscience, Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, AlbaNova University Center, 106 91, Stockholm, Sweden.
| | - Akanksha Singh
- Division of Crop Production and Protection, Central Institute of Medicinal and Aromatic Plants, Lucknow, 226015, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
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Lin J, Monsalvo I, Ly M, Jahan MA, Wi D, Martirosyan I, Kovinich N. RNA-Seq Dissects Incomplete Activation of Phytoalexin Biosynthesis by the Soybean Transcription Factors GmMYB29A2 and GmNAC42-1. PLANTS (BASEL, SWITZERLAND) 2023; 12:545. [PMID: 36771629 PMCID: PMC9921300 DOI: 10.3390/plants12030545] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/17/2023] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
Glyceollins, isoflavonoid-derived antimicrobial metabolites, are the major phytoalexins in soybean (Glycine max). They play essential roles in providing resistance to the soil-borne pathogen Phytophthora sojae and have unconventional anticancer and neuroprotective activities that render them desirable for pharmaceutical development. Our previous studies revealed that the transcription factors GmMYB29A2 and GmNAC42-1 have essential roles in activating glyceollin biosynthesis, yet each cannot activate the transcription of all biosynthesis genes in the absence of a pathogen elicitor treatment. Here, we report that co-overexpressing both transcription factors is also insufficient to activate glyceollin biosynthesis. To understand this insufficiency, we compared the transcriptome profiles of hairy roots overexpressing each transcription factor with glyceollin-synthesizing roots treated with wall glucan elicitor (WGE) from P. sojae. GmMYB29A2 upregulated most of the WGE-regulated genes that encode enzymatic steps spanning from primary metabolism to the last step of glyceollin biosynthesis. By contrast, GmNAC42-1 upregulated glyceollin biosynthesis genes only when overexpressed in the presence of WGE treatment. This is consistent with our recent discovery that, in the absence of WGE, GmNAC42-1 is bound by GmJAZ1 proteins that inhibit its transactivation activity. WGE, and not GmMYB29A2 or GmNAC42-1, upregulated the heat shock family gene GmHSF6-1, the homolog of Arabidopsis HSFB2a that directly activated the transcription of several glyceollin biosynthesis genes. Our results provide important insights into what biosynthesis genes will need to be upregulated to activate the entire glyceollin biosynthetic pathway.
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Affiliation(s)
- Jie Lin
- Department of Biology, Faculty of Science, York University, Toronto, ON M3J 1P3, Canada
| | - Ivan Monsalvo
- Department of Biology, Faculty of Science, York University, Toronto, ON M3J 1P3, Canada
| | - Melissa Ly
- Department of Biology, Faculty of Science, York University, Toronto, ON M3J 1P3, Canada
| | - Md Asraful Jahan
- Department of Genetic Engineering and Biotechnology, Shahjalal University of Science and Technology, Sylhet 3114, Bangladesh
| | - Dasol Wi
- Department of Biology, Faculty of Science, York University, Toronto, ON M3J 1P3, Canada
| | - Izabella Martirosyan
- Department of Biology, Faculty of Science, York University, Toronto, ON M3J 1P3, Canada
| | - Nik Kovinich
- Department of Biology, Faculty of Science, York University, Toronto, ON M3J 1P3, Canada
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Tsalgatidou PC, Thomloudi EE, Nifakos K, Delis C, Venieraki A, Katinakis P. Calendula officinalis-A Great Source of Plant Growth Promoting Endophytic Bacteria (PGPEB) and Biological Control Agents (BCA). Microorganisms 2023; 11:microorganisms11010206. [PMID: 36677498 PMCID: PMC9865722 DOI: 10.3390/microorganisms11010206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/08/2023] [Accepted: 01/10/2023] [Indexed: 01/15/2023] Open
Abstract
The application of beneficial bacteria may present an alternative approach to chemical plant protection and fertilization products as they enhance growth and resistance to biotic and abiotic stresses. Plant growth-promoting bacteria are found in the rhizosphere, epiphytically or endophytically (Plant Growth Promoting Endophytic Bacteria, PGPEB). In the present study, 36 out of 119 isolated endophytic bacterial strains from roots, leaves and flowers of the pharmaceutical plant Calendula officinalis were further identified and classified into Bacillus, Pseudomonas, Pantoea, Stenotrophomonas and Rhizobium genera. Selected endophytes were evaluated depending on positive reaction to different plant growth promoting (PGP) traits, motility, survival rate and inhibition of phytopathogenic fungi in vitro and ex vivo (tomato fruit). Bacteria were further assessed for their plant growth effect on Arabidopsis thaliana seedlings and on seed bio-primed tomato plantlets, in vitro. Our results indicated that many bacterial endophytes increased seed germination, promoted plant growth and changed root structure by increasing lateral root density and length and root hair formation. The most promising antagonistic PGPEB strains (Cal.r.29, Cal.l.30, Cal.f.4, Cal.l.11, Cal.f.2.1, Cal.r.19 and Cal.r.11) are indicated as effective biological control agents (BCA) against Botrytis cinerea on detached tomato fruits. Results underlie the utility of beneficial endophytic bacteria for sustainable and efficient crop production and disease control.
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Affiliation(s)
- Polina C. Tsalgatidou
- Laboratory of General and Agricultural Microbiology, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece
- Department of Agriculture, University of the Peloponnese, 24100 Kalamata, Greece
- Correspondence: (P.C.T.); (A.V.)
| | - Eirini-Evangelia Thomloudi
- Laboratory of General and Agricultural Microbiology, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece
| | - Kallimachos Nifakos
- Laboratory of General and Agricultural Microbiology, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece
- Department of Agriculture, University of the Peloponnese, 24100 Kalamata, Greece
| | - Costas Delis
- Department of Agriculture, University of the Peloponnese, 24100 Kalamata, Greece
| | - Anastasia Venieraki
- Laboratory of Plant Pathology, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece
- Correspondence: (P.C.T.); (A.V.)
| | - Panagiotis Katinakis
- Laboratory of General and Agricultural Microbiology, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece
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Salvi P, Mahawar H, Agarrwal R, Kajal, Gautam V, Deshmukh R. Advancement in the molecular perspective of plant-endophytic interaction to mitigate drought stress in plants. Front Microbiol 2022; 13:981355. [PMID: 36118190 PMCID: PMC9478035 DOI: 10.3389/fmicb.2022.981355] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 08/15/2022] [Indexed: 12/03/2022] Open
Abstract
Change in global climate has started to show its effect in the form of extremes of temperatures and water scarcity which is bound to impact adversely the global food security in near future. In the current review we discuss the impact of drought on plants and highlight the ability of endophytes, microbes that inhabit the plants asymptomatically, to confer stress tolerance to their host. For this we first describe the symbiotic association between plant and the endophytes and then focus on the molecular and physiological strategies/mechanisms adopted by these endophytes to confer stress tolerance. These include root alteration, osmotic adjustment, ROS scavenging, detoxification, production of phytohormones, and promoting plant growth under adverse conditions. The review further elaborates on how omics-based techniques have advanced our understanding of molecular basis of endophyte mediated drought tolerance of host plant. Detailed analysis of whole genome sequences of endophytes followed by comparative genomics facilitates in identification of genes involved in endophyte-host interaction while functional genomics further unveils the microbial targets that can be exploited for enhancing the stress tolerance of the host. Thus, an amalgamation of endophytes with other sustainable agricultural practices seems to be an appeasing approach to produce climate-resilient crops.
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Microbial endophytes: application towards sustainable agriculture and food security. Appl Microbiol Biotechnol 2022; 106:5359-5384. [PMID: 35902410 DOI: 10.1007/s00253-022-12078-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 07/05/2022] [Accepted: 07/11/2022] [Indexed: 02/06/2023]
Abstract
Microbial endophytes are ubiquitous and exist in each recognised plant species reported till date. Within the host plant, the entire community of microbes lives non-invasively within the active internal tissues without causing any harm to the plant. Endophytes interact with their host plant via metabolic communication enables them to generate signal molecules. In addition, the host plant's genetic recombination with endophytes helps them to imitate the host's physicochemical functions and develop identical active molecules. Therefore, when cultured separately, they begin producing the host plant phytochemicals. The fungal species Penicillium chrysogenum has portrayed the glory days of antibiotics with the invention of the antibiotic penicillin. Therefore, fungi have substantially supported social health by developing many bioactive molecules utilised as antioxidant, antibacterial, antiviral, immunomodulatory and anticancerous agents. But plant-related microbes have emanated as fountainheads of biologically functional compounds with higher levels of medicinal perspective in recent years. Researchers have been motivated by the endless need for potent drugs to investigate alternate ways to find new endophytes and bioactive molecules, which tend to be a probable aim for drug discovery. The current research trends with these promising endophytic organisms are reviewed in this review paper. KEY POINTS: • Identified 54 important bioactive compounds as agricultural relevance • Role of genome mining of endophytes and "Multi-Omics" tools in sustainable agriculture • A thorough description and graphical presentation of agricultural significance of plant endophytes.
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Oviedo-Pereira DG, López-Meyer M, Evangelista-Lozano S, Sarmiento-López LG, Sepúlveda-Jiménez G, Rodríguez-Monroy M. Enhanced specialized metabolite, trichome density, and biosynthetic gene expression in Stevia rebaudiana (Bertoni) Bertoni plants inoculated with endophytic bacteria Enterobacter hormaechei. PeerJ 2022; 10:e13675. [PMID: 35782100 PMCID: PMC9248782 DOI: 10.7717/peerj.13675] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 06/13/2022] [Indexed: 01/17/2023] Open
Abstract
Stevia rebaudiana (Bertoni) Bertoni is a plant of economic interest in the food and pharmaceutical industries due its steviol glycosides (SG), which are rich in metabolites that are 300 times sweeter than sucrose. In addition, S. rebaudiana plants contain phenolic compounds and flavonoids with antioxidant activity. Endophytic bacteria promote the growth and development and modulate the metabolism of the host plant. However, little is known regarding the role of endophytic bacteria in the growth; synthesis of SG, flavonoids and phenolic compounds; and the relationship between trichome development and specialized metabolites in S. rebaudiana, which was the subject of this study. The 12 bacteria tested did not increase the growth of S. rebaudiana plants; however, the content of SG increased with inoculation with the bacteria Enterobacter hormaechei H2A3 and E. hormaechei H5A2. The SG content in leaves paralleled an increase in the density of glandular, short, and large trichome. The image analysis of S. rebaudiana leaves showed the presence of SG, phenolic compounds, and flavonoids principally in glandular and short trichomes. The increase in the transcript levels of the KO, KAH, UGT74G1, and UGT76G1 genes was related to the SG concentration in plants of S. rebaudiana inoculated with E. hormaechei H2A3 and E. hormaechei H5A2. In conclusion, inoculation with the stimulating endophytes E. hormaechei H2A3 and E. hormaechei H5A2 increased SG synthesis, flavonoid content and flavonoid accumulation in the trichomes of S. rebaudiana plants.
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Affiliation(s)
- Dumas G. Oviedo-Pereira
- Biotecnología, Instituto Politécnico Nacional Centro de Desarrollo de Productos Bióticos, Yautepec, Morelos, México
| | - Melina López-Meyer
- Departamento de Biotecnología Agrícola, Instituto Politécnico Nacional. Centro Interdisciplinario de Investigación Para el Desarrollo Integral Regional (CIIDIR), Guasave, Sinaloa, México
| | - Silvia Evangelista-Lozano
- Biotecnología, Instituto Politécnico Nacional Centro de Desarrollo de Productos Bióticos, Yautepec, Morelos, México
| | - Luis G. Sarmiento-López
- Departamento de Biotecnología Agrícola, Instituto Politécnico Nacional. Centro Interdisciplinario de Investigación Para el Desarrollo Integral Regional (CIIDIR), Guasave, Sinaloa, México
| | - Gabriela Sepúlveda-Jiménez
- Biotecnología, Instituto Politécnico Nacional Centro de Desarrollo de Productos Bióticos, Yautepec, Morelos, México
| | - Mario Rodríguez-Monroy
- Biotecnología, Instituto Politécnico Nacional Centro de Desarrollo de Productos Bióticos, Yautepec, Morelos, México
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Singh D, Thapa S, Mahawar H, Kumar D, Geat N, Singh SK. Prospecting potential of endophytes for modulation of biosynthesis of therapeutic bioactive secondary metabolites and plant growth promotion of medicinal and aromatic plants. Antonie van Leeuwenhoek 2022; 115:699-730. [PMID: 35460457 DOI: 10.1007/s10482-022-01736-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 03/26/2022] [Indexed: 01/13/2023]
Abstract
Medicinal and aromatic plants possess pharmacological properties (antidiabetes, anticancer, antihypertension, anticardiovascular, antileprosy, etc.) because of their potential to synthesize a wide range of therapeutic bioactive secondary metabolites. The concentration of bioactive secondry metabolites depends on plant species, local environment, soil type and internal microbiome. The internal microbiome of medicinal plants plays the crucial role in the production of bioactive secondary metabolites, namely alkaloids, steroids, terpenoids, peptides, polyketones, flavonoids, quinols and phenols. In this review, the host specific secondry metabolites produced by endophytes, their therapeutic properties and host-endophytes interaction in relation to production of bioactive secondry metaboloites and the role of endophytes in enhancing the production of bioactive secondry metabolites is discussed. How biological nitrogen fixation, phosphorus solubilization, micronutrient uptake, phytohormone production, disease suppression, etc. can play a vital role in enhacing the plant growth and development.The role of endophytes in enhancing the plant growth and content of bioactive secondary metabolites in medicinal and aromatic plants in a sustainable mode is highlighted.
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Affiliation(s)
- Devendra Singh
- ICAR-Central Arid Zone Research Institute, Jodhpur, Rajasthan, 342003, India.
| | - Shobit Thapa
- ICAR-National Bureau of Agriculturally Important Microorganisms, Kushmaur, Mau Nath Bhanjan, Uttar Pradesh, 275103, India
| | - Himanshu Mahawar
- ICAR-Directorate of Weed Research (DWR), Maharajpur, Jabalpur, Madhya Pradesh, 482004, India
| | - Dharmendra Kumar
- ICAR- Central Potato Research Institute, Shimla, Himachal Pradesh, 171001, India
| | - Neelam Geat
- Agricultural Research Station, Agriculture University, Jodhpur, Rajasthan, 342304, India
| | - S K Singh
- ICAR-Central Arid Zone Research Institute, Jodhpur, Rajasthan, 342003, India
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Wu W, Wang S, Wu J, He B, Zhu B, Qin L. Influence of tissue and geographic locality on culturable endophytic bacteria of Atractylodes macrocephala. MICROBIOLOGY (READING, ENGLAND) 2021; 167. [PMID: 34825886 DOI: 10.1099/mic.0.001109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The endophytic bacterial community and their diversity are closely related to the host's growth and development. This paper explores the culturable endophytic bacteria in the stems, leaves, roots and rhizomes of Atractylodes macrocephala (AM) of four localities (Yuqian, Wenxian, Pan'an and Pingjiang) and the potential correlation between the bacteria and plant bioactive compounds. A total of 118 endophytic bacteria belonging to 3 phyla, 5 classes, 11 orders, 26 families and 48 genera were isolated and identified from the four AM tissues. Among them, Bacillus was the dominant genus. In AM, the tissue type and locality influenced the endophytic bacterial community. Approximately 29.7 and 28.8% of the endophytic bacteria exhibited tissue specificity and geographic specificity, respectively. Furthermore, high-performance liquid chromatography revealed that the sesquiterpenoid (atractylenolide I, atractylenolide Ⅱ and atractylon) content was more in the rhizomes of Wenxian than in those of Pingjiang, Yuqian and Pan'an. The multiple linear regression was used to screen the bacterial strains related to the bioactive compounds of AM. The relative frequency of Microbacterium positively correlated with atractylenolide I and atractylon content in AM but negatively correlated with atractylenolide Ⅱ content. The study also provides a theoretical framework for future research on endophytic bacteria as alternative sources of secondary plant metabolites.
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Affiliation(s)
- Wei Wu
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, PR China
| | - Shiyu Wang
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, PR China
| | - Jianjun Wu
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, PR China
| | - Bingqian He
- Academy of Chinese Medical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, PR China
| | - Bo Zhu
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, PR China
| | - Luping Qin
- School of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, PR China
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10
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Schagen M, Bosch J, Johnson J, Duker R, Lebre P, Potts AJ, Cowan DA. The soil microbiomics of intact, degraded and partially-restored semi-arid succulent thicket (Albany Subtropical Thicket). PeerJ 2021; 9:e12176. [PMID: 34707927 PMCID: PMC8501999 DOI: 10.7717/peerj.12176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 08/29/2021] [Indexed: 01/04/2023] Open
Abstract
This study examines the soil bacterial diversity in the Portulacaria afra-dominated succulent thicket vegetation of the Albany Subtropical Thicket biome; this biome is endemic to South Africa. The aim of the study was to compare the soil microbiomes between intact and degraded zones in the succulent thicket and identify environmental factors which could explain the community compositions. Bacterial diversity, using 16S amplicon sequencing, and soil physicochemistry were compared across three zones: intact (undisturbed and vegetated), degraded (near complete removal of vegetation due to browsing) and restored (a previously degraded area which was replanted approximately 11 years before sampling). Amplicon Sequence Variant (ASV) richness was similar across the three zones, however, the bacterial community composition and soil physicochemistry differed across the intact and degraded zones. We identified, via correlation, the potential drivers of microbial community composition as soil density, pH and the ratio of Ca to Mg. The restored zone was intermediate between the intact and degraded zones. The differences in the microbial communities appeared to be driven by the presence of plants, with plant-associated taxa more common in the intact zone. The dominant taxa in the degraded zone were cosmopolitan organisms, that have been reported globally in a wide variety of habitats. This study provides baseline information on the changes of the soil bacterial community of a spatially restricted and threatened biome. It also provides a starting point for further studies on community composition and function concerning the restoration of degraded succulent thicket ecosystems.
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Affiliation(s)
- Micaela Schagen
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Jason Bosch
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Jenny Johnson
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Robbert Duker
- Botany Department, South Campus, Nelson Mandela University, Port Elizabeth, Eastern Cape, South Africa
| | - Pedro Lebre
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Alastair J Potts
- Botany Department, South Campus, Nelson Mandela University, Port Elizabeth, Eastern Cape, South Africa
| | - Don A Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, Gauteng, South Africa
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11
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Bacterial Endophytes: The Hidden Actor in Plant Immune Responses against Biotic Stress. PLANTS 2021; 10:plants10051012. [PMID: 34069509 PMCID: PMC8161118 DOI: 10.3390/plants10051012] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/04/2021] [Accepted: 05/13/2021] [Indexed: 02/06/2023]
Abstract
Bacterial endophytes constitute an essential part of the plant microbiome and are described to promote plant health by different mechanisms. The close interaction with the host leads to important changes in the physiology of the plant. Although beneficial bacteria use the same entrance strategies as bacterial pathogens to colonize and enter the inner plant tissues, the host develops strategies to select and allow the entrance to specific genera of bacteria. In addition, endophytes may modify their own genome to adapt or avoid the defense machinery of the host. The present review gives an overview about bacterial endophytes inhabiting the phytosphere, their diversity, and the interaction with the host. Direct and indirect defenses promoted by the plant-endophyte symbiont exert an important role in controlling plant defenses against different stresses, and here, more specifically, is discussed the role against biotic stress. Defenses that should be considered are the emission of volatiles or antibiotic compounds, but also the induction of basal defenses and boosting plant immunity by priming defenses. The primed defenses may encompass pathogenesis-related protein genes (PR family), antioxidant enzymes, or changes in the secondary metabolism.
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Mishra S, Goyal D, Phurailatpam L. Targeted 16S rRNA gene and ITS2 amplicon sequencing of leaf and spike tissues of Piper longum identifies new candidates for bioprospecting of bioactive compounds. Arch Microbiol 2021; 203:3851-3867. [PMID: 34013420 DOI: 10.1007/s00203-021-02356-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 04/27/2021] [Accepted: 05/03/2021] [Indexed: 12/19/2022]
Abstract
Piper longum (also known as Indian long pepper) is widely used in Ayurvedic, Siddha and Unani medicine systems. The principle bioactive compound of this plant is piperine, which mainly accumulates in the fruits called spikes. The report of piperine production by endophytic microbes isolated from Piper sp., motivated us to investigate the endophytic microbial diversity associated with the spikes vis-à-vis leaves (which contain negligible levels of piperine). This is the first report to use metagenomics approach to unravel the endophytic microbial diversity in P. longum. Our results indicate that 2, 56, 631 bacterial OTUs and 1090 fungal OTUs were picked cumulatively from both the tissues. Although bacterial and fungal endophytes occupy the same niche, remarkable differences exist in their diversity and abundance. For instance, the most abundant bacterial genera in spikes were Nocardioides and Pseudonocardia (Phylum Actinobacteria; reported to produce bioactive compounds); while, in leaves were Larkinella and Hymenobacter (Phylum Bacteriodetes). Likewise, the fungal endophytes, Periconia, Cladosporium and Coniothyrium (which have been earlier reported to produce commercially important metabolites including piperine), were also present in high abundance in spikes, in comparison to leaves. Further, the results of PICRUSt analysis reveal the high metabolic potential of spike-associated bacteria for secondary metabolism, namely biosynthesis of alkaloids (including pyridine/piperidine), terpenes, flavonoids and antibiotics. Therefore, our findings indicate that the endophytes abundant or unique in spikes could be explored for bioprospecting of novel/commercially important metabolites; an approach that has both ecological and economical benefits.
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Affiliation(s)
- Sushma Mishra
- Plant Biotechnology Lab, Department of Botany, Faculty of Science, Dayalbagh Educational Institute (Deemed-to-be-University), Agra, Uttar Pradesh, India.
| | - Deepika Goyal
- Plant Biotechnology Lab, Department of Botany, Faculty of Science, Dayalbagh Educational Institute (Deemed-to-be-University), Agra, Uttar Pradesh, India
| | - Laccy Phurailatpam
- Plant Biotechnology Lab, Department of Botany, Faculty of Science, Dayalbagh Educational Institute (Deemed-to-be-University), Agra, Uttar Pradesh, India
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13
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Wu W, Chen W, Liu S, Wu J, Zhu Y, Qin L, Zhu B. Beneficial Relationships Between Endophytic Bacteria and Medicinal Plants. FRONTIERS IN PLANT SCIENCE 2021; 12:646146. [PMID: 33968103 PMCID: PMC8100581 DOI: 10.3389/fpls.2021.646146] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 04/06/2021] [Indexed: 05/03/2023]
Abstract
Plants benefit extensively from endophytic bacteria, which live in host plant tissues exerting no harmful effects. Bacterial endophytes promote the growth of host plants and enhance their resistance toward various pathogens and environmental stresses. They can also regulate the synthesis of secondary metabolites with significant medicinal properties and produce various biological effects. This review summarizes recent studies on the relationships between bacterial endophytes and medicinal plants. Endophytic bacteria have numerous applications in agriculture, medicine, and other industries: improving plant growth, promoting resistance toward both biotic and abiotic stresses, and producing metabolites with medicinal potential. Their distribution and population structure are affected by their host plant's genetic characteristics and health and by the ecology of the surrounding environment. Understanding bacterial endophytes can help us use them more effectively and apply them to medicinal plants to improve yield and quality.
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Affiliation(s)
| | | | | | | | | | - Luping Qin
- School of Pharmacy, Zhejiang Chinese Medical University, Hangzhou, China
| | - Bo Zhu
- School of Pharmacy, Zhejiang Chinese Medical University, Hangzhou, China
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14
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Castronovo LM, Vassallo A, Mengoni A, Miceli E, Bogani P, Firenzuoli F, Fani R, Maggini V. Medicinal Plants and Their Bacterial Microbiota: A Review on Antimicrobial Compounds Production for Plant and Human Health. Pathogens 2021; 10:pathogens10020106. [PMID: 33498987 PMCID: PMC7911374 DOI: 10.3390/pathogens10020106] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/20/2021] [Accepted: 01/21/2021] [Indexed: 12/15/2022] Open
Abstract
Medicinal plants (MPs) have been used since antiquity in traditional and popular medicine, and they represent a very important source of bioactive molecules, including antibiotic, antiviral, and antifungal molecules. Such compounds are often of plant origin, but in some cases, an origin or a modification from plant microbiota has been shown. Actually, the research continues to report the production of bioactive molecules by plants, but the role of plant–endophytic interaction is emerging. Classic examples are mainly concerned with fungal endophytes; however, it has been recently shown that bacterial endophytes can also play an important role in influencing the plant metabolism related to the synthesis of bioactive compounds. In spite of this, a deep investigation on the power of MP bacterial endophytes is lacking. Here, an overview of the studies on MP bacterial microbiota and its role in the production of plant antimicrobial compounds contributing to prime host defense system and representing a huge resource for biotech and therapeutic applications is provided.
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Affiliation(s)
- Lara Mitia Castronovo
- Department of Biology, University of Florence, 50019 Florence, Italy; (L.M.C.); (A.V.); (A.M.); (E.M.); (P.B.)
| | - Alberto Vassallo
- Department of Biology, University of Florence, 50019 Florence, Italy; (L.M.C.); (A.V.); (A.M.); (E.M.); (P.B.)
| | - Alessio Mengoni
- Department of Biology, University of Florence, 50019 Florence, Italy; (L.M.C.); (A.V.); (A.M.); (E.M.); (P.B.)
| | - Elisangela Miceli
- Department of Biology, University of Florence, 50019 Florence, Italy; (L.M.C.); (A.V.); (A.M.); (E.M.); (P.B.)
| | - Patrizia Bogani
- Department of Biology, University of Florence, 50019 Florence, Italy; (L.M.C.); (A.V.); (A.M.); (E.M.); (P.B.)
| | - Fabio Firenzuoli
- CERFIT, Research and Innovation Center in Phytotherapy and Integrated Medicine, Tuscany Region, Careggi University Hospital, 50141 Florence, Italy;
| | - Renato Fani
- Department of Biology, University of Florence, 50019 Florence, Italy; (L.M.C.); (A.V.); (A.M.); (E.M.); (P.B.)
- Correspondence: (R.F.); (V.M.); Tel.: +39-0554574742 (R.F.); +39-0554574731 (V.M.)
| | - Valentina Maggini
- Department of Biology, University of Florence, 50019 Florence, Italy; (L.M.C.); (A.V.); (A.M.); (E.M.); (P.B.)
- CERFIT, Research and Innovation Center in Phytotherapy and Integrated Medicine, Tuscany Region, Careggi University Hospital, 50141 Florence, Italy;
- Correspondence: (R.F.); (V.M.); Tel.: +39-0554574742 (R.F.); +39-0554574731 (V.M.)
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15
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Dubey A, Malla MA, Kumar A, Dayanandan S, Khan ML. Plants endophytes: unveiling hidden agenda for bioprospecting toward sustainable agriculture. Crit Rev Biotechnol 2020; 40:1210-1231. [PMID: 32862700 DOI: 10.1080/07388551.2020.1808584] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Endophytic microbes are present in nearly all of the plant species known to date but how they enter and flourish inside a host plant and display multiple benefits like plant growth promotion (PGP), biodegradation, and stress alleviation are still unexplored. Until now, the majority of the research has been conducted assuming that the host-endophyte interaction is analogous to the PGP microbes, although, studies related to the mechanisms of their infection, colonization as well as conferring important traits to the plants are limited. It would be fascinating to explore the role of these endophytic microbes in host gene expression, metabolism, and the modulation of phenotypic traits, under abiotic and biotic stress conditions. In this review, we critically focused on the following areas: (i) endophytic lifestyle and the mechanism of their entry into plant tissues, (ii) how endophytes modulate the immune system of plants and affect the genotypic and phenotypic expression of host plants under abiotic and biotic stress condition, and (iii) the role of omics and other integrated genomic approaches in unraveling complex host-endophyte signaling crosstalk. Furthermore, we discussed their role in phytoremediation of heavy metal stress and whole genomic analysis based on an understanding of different metabolic pathways these endophytes utilize to combat stress.
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Affiliation(s)
- Anamika Dubey
- Department of Botany, Metagenomics and Secretomics Research Laboratory, Dr. Harisingh Gour University (A Central University), Sagar, India
| | - Muneer Ahmad Malla
- Department of Zoology, Dr. Harisingh Gour University (A Central University), Sagar, India
| | - Ashwani Kumar
- Department of Botany, Metagenomics and Secretomics Research Laboratory, Dr. Harisingh Gour University (A Central University), Sagar, India
| | - Selvadurai Dayanandan
- Department of Zoology, Dr. Harisingh Gour University (A Central University), Sagar, India.,Biology Department, Centre for Structural and Functional Genomics, Concordia University, Montreal, QC, Canada
| | - Mohammad Latif Khan
- Department of Botany, Metagenomics and Secretomics Research Laboratory, Dr. Harisingh Gour University (A Central University), Sagar, India
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16
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Taghinasab M, Jabaji S. Cannabis Microbiome and the Role of Endophytes in Modulating the Production of Secondary Metabolites: An Overview. Microorganisms 2020; 8:E355. [PMID: 32131457 PMCID: PMC7143057 DOI: 10.3390/microorganisms8030355] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 02/26/2020] [Accepted: 02/28/2020] [Indexed: 12/19/2022] Open
Abstract
Plants, including cannabis (Cannabis sativa subsp. sativa), host distinct beneficial microbial communities on and inside their tissues and organs, including seeds. They contribute to plant growth, facilitating mineral nutrient uptake, inducing defence resistance against pathogens, and modulating the production of plant secondary metabolites. Understanding the microbial partnerships with cannabis has the potential to affect the agricultural practices by improving plant fitness and the yield of cannabinoids. Little is known about this beneficial cannabis-microbe partnership, and the complex relationship between the endogenous microbes associated with various tissues of the plant, and the role that cannabis may play in supporting or enhancing them. This review will consider cannabis microbiota studies and the effects of endophytes on the elicitation of secondary metabolite production in cannabis plants. The review aims to shed light on the importance of the cannabis microbiome and how cannabinoid compound concentrations can be stimulated through symbiotic and/or mutualistic relationships with endophytes.
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Affiliation(s)
| | - Suha Jabaji
- Plant Science Department, Faculty of Agricultural and Environmental Sciences, MacDonald Campus of McGill University, QC H9X 3V9, Canada;
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17
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Singh S, Pandey SS, Shanker K, Kalra A. Endophytes enhance the production of root alkaloids ajmalicine and serpentine by modulating the terpenoid indole alkaloid pathway in Catharanthus roseus roots. J Appl Microbiol 2020; 128:1128-1142. [PMID: 31821696 DOI: 10.1111/jam.14546] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 10/15/2019] [Accepted: 11/28/2019] [Indexed: 12/15/2022]
Abstract
AIM The aim of this study was to identify and characterize promising endophytes capable of enhancing the content of root alkaloids ajmalicine and serpentine in low alkaloid yielding genotype of Catharanthus roseus cultivar Prabal and the possible mechanisms involved. METHOD AND RESULT Of the four strains isolated from alkaloid-rich genotype of C. roseus cultivar Dhawal, endophytic strains CATDLF5 (Curvularia sp.) and CATDLF6 (Choanephora infundibulifera) enhanced serpentine content by 211·7-337·6%, while CATDRF2 (Aspergillus japonicus) and CATDS5 (Pseudomonas sp.) increased the content of ajmalicine by 123·4-203·8% in cultivar Prabal. Upregulated expression of key genes, geraniol 10-hydroxylase, tryptophan decarboxylase and strictosidine synthase involved in terpenoid indole alkaloid (TIA) biosynthetic pathway was observed in endophyte inoculated plants. Upregulated Octadecanoid-derivative Responsive Catharanthus AP2/ERF domain transcription activators like ORCA3 while, and downregulation of transcriptional repressor, ZCTs (Cys2/His2-type zinc finger protein family) enhanced the expression of genes for secondary metabolite production in endophyte-inoculated plants. CONCLUSION The present work concluded that the selected endophytes of C. roseus can enhance the ajmalicine and serpentine contents by modulating the expression of structural and regulatory genes of TIA biosynthetic pathway in root. SIGNIFICANCE AND IMPACT OF THE STUDY Endophytes can play an important role to enhance in planta content of pharmaceutically important alkaloids in C. roseus and can therefore be useful in reducing the cost of production of important alkaloids.
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Affiliation(s)
- S Singh
- Microbial Technology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
| | - S S Pandey
- Microbial Technology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh, India
| | - K Shanker
- Analytical Chemistry Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh, India
| | - A Kalra
- Microbial Technology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
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18
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Ray T, Pandey SS, Pandey A, Srivastava M, Shanker K, Kalra A. Endophytic Consortium With Diverse Gene-Regulating Capabilities of Benzylisoquinoline Alkaloids Biosynthetic Pathway Can Enhance Endogenous Morphine Biosynthesis in Papaver somniferum. Front Microbiol 2019; 10:925. [PMID: 31114562 PMCID: PMC6503101 DOI: 10.3389/fmicb.2019.00925] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 04/11/2019] [Indexed: 11/21/2022] Open
Abstract
Secondary metabolite biosynthesis in medicinal plants is multi-step cascade known to be modulated by associated endophytes. While a single endophyte is not able to upregulate all biosynthetic steps, limiting maximum yield achievement. Therefore to compliment the deficient characteristics in an endophyte we tried consortium of endophytes to achieve maximum yield. Here, efforts were made to maximize the in planta morphine yield, using consortium of two endophytes; SM1B (Acinetobacter sp.) upregulating most of the genes of morphine biosynthesis except T6ODM and CODM, and SM3B (Marmoricola sp.) upregulating T6ODM and CODM in alkaloid-less Papaver somniferum cv. Sujata. Consortium-inoculation significantly increased morphine and thebaine content, and also increased the photosynthetic efficiency of poppy plants resulted in increased biomass, capsule weight, and seed yields compared to single-inoculation. The increment in morphine content was due to the modulation of metabolic-flow of key intermediates including reticuline and thebaine, via upregulating pertinent biosynthetic genes and enhanced expression of COR, key gene for morphine biosynthesis. This is the first report demonstrating the endophytic-consortium complimenting the functional deficiency of one endophyte by another for upregulating multiple genes of a metabolic pathway similar to transgenics (overexpressing multiple genes) for obtaining enhanced yield of pharmaceutically important metabolites.
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Affiliation(s)
- Tania Ray
- Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Shiv S Pandey
- Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Alok Pandey
- Biotechnology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Madhumita Srivastava
- Analytical Chemistry Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Karuna Shanker
- Analytical Chemistry Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Alok Kalra
- Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
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19
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Khare E, Mishra J, Arora NK. Multifaceted Interactions Between Endophytes and Plant: Developments and Prospects. Front Microbiol 2018; 9:2732. [PMID: 30498482 PMCID: PMC6249440 DOI: 10.3389/fmicb.2018.02732] [Citation(s) in RCA: 238] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Accepted: 10/25/2018] [Indexed: 11/13/2022] Open
Abstract
Microbial endophytes are present in all known plant species. The ability to enter and thrive in the plant tissues makes endophytes unique, showing multidimensional interactions within the host plant. Several vital activities of the host plant are known to be influenced by the presence of endophytes. They can promote plant growth, elicit defense response against pathogen attack, and can act as remediators of abiotic stresses. To date, most of the research has been done assuming that the interaction of endophytes with the host plant is similar to the plant growth-promoting (PGP) microbes present in the rhizosphere. However, a new appreciation of the difference of the rhizosphere environment from that of internal plant tissues is gaining attention. It would be interesting to explore the impact of endosymbionts on the host’s gene expression, metabolism, and other physiological aspects essential in conferring resistance against biotic and abiotic stresses. A more intriguing and inexplicable issue with many endophytes that has to be critically evaluated is their ability to produce host metabolites, which can be harnessed on a large scale for potential use in diverse areas. In this review, we discuss the concept of endophytism, looking into the latest insights related to the multifarious interactions beneficial for the host plant and exploring the importance of these associations in agriculture and the environment and in other vital aspects such as human health.
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Affiliation(s)
- Ekta Khare
- Department of Microbiology, Institute of Biosciences and Biotechnology, Chhatrapati Shahu Ji Maharaj University, Kanpur, India
| | - Jitendra Mishra
- Department of Microbiology, Babasaheb Bhimrao Ambedkar University, Lucknow, India
| | - Naveen Kumar Arora
- Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Lucknow, India
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20
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Purushotham N, Jones E, Monk J, Ridgway H. Community Structure of Endophytic Actinobacteria in a New Zealand Native Medicinal Plant Pseudowintera colorata (Horopito) and Their Influence on Plant Growth. MICROBIAL ECOLOGY 2018; 76:729-740. [PMID: 29435598 DOI: 10.1007/s00248-018-1153-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 01/30/2018] [Indexed: 06/08/2023]
Abstract
The role of plant endophytic Actinobacteria remains poorly understood with no reports of these communities in New Zealand native plants. This first investigation of endophytic Actinobacteria in New Zealand targeted the culturally significant medicinal shrub Pseudowintera colorata (horopito) as a model plant. Community analysis in plant tissues collected from ten geographically distinct sites showed that tissue type had the strongest influence on diversity and richness of endophytic Actinobacteria. More denaturing gradient gel electrophoresis (DGGE) bands were obtained from stems (n = 18) compared to roots (n = 13). Sequencing analysis of the major bands (n = 20) identified them as uncultured bacteria, Streptomyces sp. and Angustibacter peucedani. Using two Actinobacteria-specific media, nine isolates were recovered from surface-sterilised P. colorata tissues. This was approximately 12% of the total taxa and correlated well with culturable numbers in international studies. In vitro analysis of the functionality of these strains showed that Streptomyces sp. PRY2RB2 inhibited all the tested phytopathogenic fungi (n = 4), Streptomyces sp. UKCW/B and Nocardia sp. TP1BA1B solubilised phosphate and produced siderophores. The functionality of the phosphate solubilising strains (n = 2) in vivo was investigated by inoculation of P. colorata seedlings. After 4 months, the mean shoot height of seedlings treated with Nocardia sp. TP1BA1B was 1.65× longer, had higher shoot dry weight (1.6×) and number of internodes (1.67×) compared to control. This study identified for the first time a key group of endophytic Actinobacteria that are likely to be important in the ecology of New Zealand flora.
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Affiliation(s)
- Neeraj Purushotham
- Department of Pest-management and Conservation, Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, New Zealand.
| | - Eirian Jones
- Department of Pest-management and Conservation, Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, New Zealand
| | - Jana Monk
- AgResearch, Christchurch, New Zealand
- AsureQuality, Christchurch, New Zealand
| | - Hayley Ridgway
- Department of Pest-management and Conservation, Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, New Zealand
- Plant & Food Research Ltd, Christchurch, New Zealand
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21
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Chagas FO, Pessotti RDC, Caraballo-Rodríguez AM, Pupo MT. Chemical signaling involved in plant-microbe interactions. Chem Soc Rev 2018; 47:1652-1704. [PMID: 29218336 DOI: 10.1039/c7cs00343a] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Microorganisms are found everywhere, and they are closely associated with plants. Because the establishment of any plant-microbe association involves chemical communication, understanding crosstalk processes is fundamental to defining the type of relationship. Although several metabolites from plants and microbes have been fully characterized, their roles in the chemical interplay between these partners are not well understood in most cases, and they require further investigation. In this review, we describe different plant-microbe associations from colonization to microbial establishment processes in plants along with future prospects, including agricultural benefits.
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Affiliation(s)
- Fernanda Oliveira Chagas
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (FCFRP-USP), Avenida do Café, s/n, 14040-903, Ribeirão Preto-SP, Brazil.
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22
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Li M, Yang Y, He Y, Mathieu J, Yu C, Li Q, Alvarez PJJ. Detection and cell sorting of Pseudonocardia species by fluorescence in situ hybridization and flow cytometry using 16S rRNA-targeted oligonucleotide probes. Appl Microbiol Biotechnol 2018; 102:3375-3386. [DOI: 10.1007/s00253-018-8801-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 12/19/2017] [Accepted: 01/21/2018] [Indexed: 10/18/2022]
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23
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Etalo D, Jeon JS, Raaijmakers JM. Modulation of plant chemistry by beneficial root microbiota. Nat Prod Rep 2018; 35:398-409. [DOI: 10.1039/c7np00057j] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Beneficial root microbiota modulate plant chemistry and represent an untapped potential to discover new pathways involved in the biosynthesis of high value natural plant products.
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Affiliation(s)
- Desalegn W. Etalo
- Netherlands Institute of Ecology NIOO-KNAW
- Department of Microbial Ecology
- Wageningen
- Netherlands
| | - Je-Seung Jeon
- Netherlands Institute of Ecology NIOO-KNAW
- Department of Microbial Ecology
- Wageningen
- Netherlands
- Institute of Biology
| | - Jos M. Raaijmakers
- Netherlands Institute of Ecology NIOO-KNAW
- Department of Microbial Ecology
- Wageningen
- Netherlands
- Institute of Biology
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24
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Singh M, Kumar A, Singh R, Pandey KD. Endophytic bacteria: a new source of bioactive compounds. 3 Biotech 2017; 7:315. [PMID: 28955612 DOI: 10.1007/s13205-017-0942-z] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 09/05/2017] [Indexed: 12/20/2022] Open
Abstract
In recent years, bioactive compounds are in high demand in the pharmaceuticals and naturopathy, due to their health benefits to human and plants. Microorganisms synthesize these compounds and some enzymes either alone or in association with plants. Microbes residing inside the plant tissues, known as endophytes, also produce an array of these compounds. Endophytic actinomycetes act as a promising resource of biotechnologically valuable bioactive compounds and secondary metabolites. Endophytic Streptomyces sp. produced some novel antibiotics which are effective against multi-drug-resistant bacteria Antimicrobial agents produced by endophytes are eco-friendly, toxic to pathogens and do not harm the human. Endophytic inoculation of the plants modulates the synthesis of bioactive compounds with high pharmaceutical properties besides promoting growth of the plants. Hydrolases, the extracellular enzymes, produced by endophytic bacteria, help the plants to establish systemic resistance against pathogens invasion. Phytohormones produced by endophytes play an essential role in plant development and drought resistance management. The high diversity of endophytes and their adaptation to various environmental stresses seem to be an untapped source of new secondary metabolites. The present review summarizes the role of endophytic bacteria in synthesis and modulation of bioactive compounds.
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25
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Dinesh R, Srinivasan V, T E S, Anandaraj M, Srambikkal H. Endophytic actinobacteria: Diversity, secondary metabolism and mechanisms to unsilence biosynthetic gene clusters. Crit Rev Microbiol 2017; 43:546-566. [PMID: 28358596 DOI: 10.1080/1040841x.2016.1270895] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Endophytic actinobacteria, which reside in the inner tissues of host plants, are gaining serious attention due to their capacity to produce a plethora of secondary metabolites (e.g. antibiotics) possessing a wide variety of biological activity with diverse functions. This review encompasses the recent reports on endophytic actinobacterial species diversity, in planta habitats and mechanisms underlying their mode of entry into plants. Besides, their metabolic potential, novel bioactive compounds they produce and mechanisms to unravel their hidden metabolic repertoire by activation of cryptic or silent biosynthetic gene clusters (BGCs) for eliciting novel secondary metabolite production are discussed. The study also reviews the classical conservative techniques (chemical/biological/physical elicitation, co-culturing) as well as modern microbiology tools (e.g. next generation sequencing) that are being gainfully employed to uncover the vast hidden scaffolds for novel secondary metabolites produced by these endophytes, which would subsequently herald a revolution in drug engineering. The potential role of these endophytes in the agro-environment as promising biological candidates for inhibition of phytopathogens and the way forward to thoroughly exploit this unique microbial community by inducing expression of cryptic BGCs for encoding unseen products with novel therapeutic properties are also discussed.
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Affiliation(s)
- Raghavan Dinesh
- a ICAR-Indian Institute of Spices Research , Kozhikode, Kerala , India
| | | | - Sheeja T E
- a ICAR-Indian Institute of Spices Research , Kozhikode, Kerala , India
| | | | - Hamza Srambikkal
- a ICAR-Indian Institute of Spices Research , Kozhikode, Kerala , India
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26
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Potential of Endophytic Bacterium Paenibacillus sp. PHE-3 Isolated from Plantago asiatica L. for Reduction of PAH Contamination in Plant Tissues. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:ijerph13070633. [PMID: 27347988 PMCID: PMC4962174 DOI: 10.3390/ijerph13070633] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/01/2016] [Accepted: 06/11/2016] [Indexed: 11/17/2022]
Abstract
Endophytes are ubiquitous in plants, and they may have a natural capacity to biodegrade polycyclic aromatic hydrocarbons (PAHs). In our study, a phenanthrene-degrading endophytic Paenibacillus sp. PHE-3 was isolated from P. asiatica L. grown in a PAH-contaminated site. The effects of environmental variables on phenanthrene biodegradation by strain PHE-3 were studied, and the ability of strain PHE-3 to use high molecular weight PAH (HMW-PAH) as a sole carbon source was also evaluated. Our results indicated that pH value of 4.0–8.0, temperature of 30 °C–42 °C, initial phenanthrene concentration less than 100 mg·L−1, and some additional nutrients are favorable for the biodegradation of phenanthrene by strain PHE-3. The maximum biodegradation efficiency of phenanthrene was achieved at 99.9% after 84 h cultivation with additional glutamate. Moreover, the phenanthrene biodegradation by strain PHE-3 was positively correlated with the catechol 2,3-dioxygenase activity (ρ = 0.981, p < 0.05), suggesting that strain PHE-3 had the capability of degrading HMW-PAHs. In the presence of other 2-, 3-ringed PAHs, strain PHE-3 effectively degraded HMW-PAHs through co-metabolism. The results of this study are beneficial in that the re-colonization potential and PAH degradation performance of endophytic Paenibacillus sp. PHE-3 may be applied towards reducing PAH contamination in plants.
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Pandey SS, Singh S, Babu CSV, Shanker K, Srivastava NK, Shukla AK, Kalra A. Fungal endophytes of Catharanthus roseus enhance vindoline content by modulating structural and regulatory genes related to terpenoid indole alkaloid biosynthesis. Sci Rep 2016; 6:26583. [PMID: 27220774 PMCID: PMC4879578 DOI: 10.1038/srep26583] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 04/13/2016] [Indexed: 01/09/2023] Open
Abstract
Not much is known about the mechanism of endophyte-mediated induction of secondary metabolite production in Catharanthus roseus. In the present study two fungal endophytes, Curvularia sp. CATDLF5 and Choanephora infundibulifera CATDLF6 were isolated from the leaves of the plant that were found to enhance vindoline content by 229-403%. The isolated endophytes did not affect the primary metabolism of the plant as the maximum quantum efficiency of PSII, net CO2 assimilation, plant biomass and starch content of endophyte-inoculated plants was similar to endophyte-free control plants. Expression of terpenoid indole alkaloid (TIA) pathway genes, geraniol 10-hydroxylase (G10H), tryptophan decarboxylase (TDC), strictosidine synthase (STR), 16-hydoxytabersonine-O-methyltransferase (16OMT), desacetoxyvindoline-4-hydroxylase (D4H), deacetylvindoline-4-O-acetyltransferase (DAT) were upregulated in endophyte-inoculated plants. Endophyte inoculation upregulated the expression of the gene for transcriptional activator octadecanoid-responsive Catharanthus AP2-domain protein (ORCA3) and downregulated the expression of Cys2/His2-type zinc finger protein family transcriptional repressors (ZCTs). The gene for the vacuolar class III peroxidase (PRX1), responsible for coupling vindoline and catharanthine, was upregulated in endophyte-inoculated plants. These endophytes may enhance vindoline production by modulating the expression of key structural and regulatory genes of vindoline biosynthesis without affecting the primary metabolism of the host plant.
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Affiliation(s)
- Shiv S. Pandey
- Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow-226015, India
| | - Sucheta Singh
- Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow-226015, India
| | - C. S. Vivek Babu
- CSIR-Central Institute of Medicinal and Aromatic Plants, Research Centre, Allalasandra, GKVK Post, Bangalore-560065, India
| | - Karuna Shanker
- Analytical Chemistry Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow-226015, India
| | - N. K. Srivastava
- Plant Physiology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow-226015, India
| | - Ashutosh K. Shukla
- Biotechnology Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow-226015, India
| | - Alok Kalra
- Microbial Technology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow-226015, India
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Arora M, Saxena P, Choudhary DK, Abdin MZ, Varma A. Dual symbiosis between Piriformospora indica and Azotobacter chroococcum enhances the artemisinin content in Artemisia annua L. World J Microbiol Biotechnol 2016; 32:19. [PMID: 26745979 DOI: 10.1007/s11274-015-1972-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 11/12/2015] [Indexed: 11/25/2022]
Abstract
At present, Artemisia annua L. is the major source of artemisinin production. To control the outbreaks of malaria, artemisinin combination therapies (ACTs) are recommended, and hence an ample amount of artemisinin is required for ACTs manufacture to save millions of lives. The low yield of this antimalarial drug in A. annua L. plants (0.01-1.1%) ensues its short supply and high cost, thus making it a topic of scrutiny worldwide. In this study, the effects of root endophyte, Piriformospora indica strain DSM 11827 and nitrogen fixing bacterium, Azotobacter chroococcum strain W-5, either singly and/or in combination for artemisinin production in A. annua L. plants have been studied under poly house conditions. The plant growth was monitored by measuring parameters like height of plant, total dry weight and leaf yield with an increase of 63.51, 52.61 and 79.70% respectively, for treatment with dual biological consortium, as compared to that of control plants. This significant improvement in biomass was associated with higher total chlorophyll content (59.29%) and enhanced nutrition (especially nitrogen and phosphorus, 55.75 and 86.21% respectively). The concentration of artemisinin along with expression patterns of artemisinin biosynthesis genes were appreciably higher in dual treatment, which showed positive correlation. The study suggested the potential use of the consortium P. indica strain DSM 11827 and A. chroococcum strain W-5 in A. annua L. plants for increased overall productivity and sustainable agriculture.
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Affiliation(s)
- Monika Arora
- Amity Institute of Microbial Technology (AIMT), Block 'E-3', 4th Floor, Amity University Campus, Sector-125, Gautam Buddha Nagar, Noida, UP, 201313, India
| | - Parul Saxena
- Centre for Transgenic Plant Development, Faculty of Science, Hamdard University, New Delhi, India
| | - Devendra Kumar Choudhary
- Amity Institute of Microbial Technology (AIMT), Block 'E-3', 4th Floor, Amity University Campus, Sector-125, Gautam Buddha Nagar, Noida, UP, 201313, India
| | - Malik Zainul Abdin
- Centre for Transgenic Plant Development, Faculty of Science, Hamdard University, New Delhi, India
| | - Ajit Varma
- Amity Institute of Microbial Technology (AIMT), Block 'E-3', 4th Floor, Amity University Campus, Sector-125, Gautam Buddha Nagar, Noida, UP, 201313, India.
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Zhou JY, Yuan J, Li X, Ning YF, Dai CC. Endophytic Bacterium-Triggered Reactive Oxygen Species Directly Increase Oxygenous Sesquiterpenoid Content and Diversity in Atractylodes lancea. Appl Environ Microbiol 2015; 82:1577-1585. [PMID: 26712554 PMCID: PMC4771314 DOI: 10.1128/aem.03434-15] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 12/21/2015] [Indexed: 12/25/2022] Open
Abstract
Oxygenous terpenoids are active components of many medicinal plants. However, current studies that have focused on enzymatic oxidation reactions cannot comprehensively clarify the mechanisms of oxygenous terpenoid synthesis and diversity. This study shows that an endophytic bacterium can trigger the generation of reactive oxygen species (ROS) that directly increase oxygenous sesquiterpenoid content and diversity in Atractylodes lancea. A. lancea is a famous but endangered Chinese medicinal plant that contains abundant oxygenous sesquiterpenoids. Geo-authentic A. lancea produces a wider range and a greater abundance of oxygenous sesquiterpenoids than the cultivated herb. Our previous studies have shown the mechanisms behind endophytic promotion of the production of sesquiterpenoid hydrocarbon scaffolds; however, how endophytes promote the formation of oxygenous sesquiterpenoids and their diversity is unclear. After colonization by Pseudomonas fluorescens ALEB7B, oxidative burst and oxygenous sesquiterpenoid accumulation in A. lancea occur synchronously. Treatment with exogenous hydrogen peroxide (H2O2) or singlet oxygen induces oxidative burst and promotes oxygenous sesquiterpenoid accumulation in planta. Conversely, pretreatment of plantlets with the ROS scavenger ascorbic acid significantly inhibits the oxidative burst and oxygenous sesquiterpenoid accumulation induced by P. fluorescens ALEB7B. Further in vitro oxidation experiments show that several oxygenous sesquiterpenoids can be obtained from direct oxidation caused by H2O2 or singlet oxygen. In summary, this study demonstrates that endophytic bacterium-triggered ROS can directly oxidize oxygen-free sesquiterpenoids and increase the oxygenous sesquiterpenoid content and diversity in A. lancea, providing a novel explanation of the mechanisms of oxygenous terpenoid synthesis in planta and an essential complementarity to enzymatic oxidation reactions.
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Affiliation(s)
- Jia-Yu Zhou
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu Province, China
| | - Jie Yuan
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu Province, China
| | - Xia Li
- Jiangsu High Quality Rice Research and Development Center, Nanjing Branch of China National Center Rice Improvement, Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu Province, China
| | - Yi-Fan Ning
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu Province, China
| | - Chuan-Chao Dai
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu Province, China
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Passari AK, Mishra VK, Gupta VK, Yadav MK, Saikia R, Singh BP. In Vitro and In Vivo Plant Growth Promoting Activities and DNA Fingerprinting of Antagonistic Endophytic Actinomycetes Associates with Medicinal Plants. PLoS One 2015; 10:e0139468. [PMID: 26422789 PMCID: PMC4589368 DOI: 10.1371/journal.pone.0139468] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 09/14/2015] [Indexed: 11/18/2022] Open
Abstract
Endophytic actinomycetes have shown unique plant growth promoting as well as antagonistic activity against fungal phytopathogens. In the present study forty-two endophytic actinomycetes recovered from medicinal plants were evaluated for their antagonistic potential and plant growth-promoting abilities. Twenty-two isolates which showed the inhibitory activity against at least one pathogen were subsequently tested for their plant-growth promoting activities and were compared genotypically using DNA based fingerprinting, including enterobacterial repetitive intergenic consensus (ERIC) and BOX repetitive elements. Genetic relatedness based on both ERIC and BOX-PCR generates specific patterns corresponding to particular genotypes. Exponentially grown antagonistic isolates were used to evaluate phosphate solubilization, siderophores, HCN, ammonia, chitinase, indole-3-acetic acid production, as well as antifungal activities. Out of 22 isolates, the amount of indole-3-acetic acid (IAA) ranging between 10–32 μg/ml was produced by 20 isolates and all isolates were positive for ammonia production ranging between 5.2 to 54 mg/ml. Among 22 isolates tested, the amount of hydroxamate-type siderophores were produced by 16 isolates ranging between 5.2 to 36.4 μg/ml, while catechols-type siderophores produced by 5 isolates ranging from 3.2 to 5.4 μg/ml. Fourteen isolates showed the solubilisation of inorganic phosphorous ranging from 3.2 to 32.6 mg/100ml. Chitinase and HCN production was shown by 19 and 15 different isolates, respectively. In addition, genes of indole acetic acid (iaaM) and chitinase (chiC) were successively amplified from 20 and 19 isolates respectively. The two potential strains Streptomyces sp. (BPSAC34) and Leifsonia xyli (BPSAC24) were tested in vivo and improved a range of growth parameters in chilli (Capsicum annuum L.) under greenhouse conditions. This study is the first published report that actinomycetes can be isolated as endophytes from within these plants and were shown to have antagonistic and plant growth promoting abilities. These results clearly suggest the possibility of using endophytic actinomycetes as bioinoculant for plant growth promotion, nutrient mobilization or as biocontrol agent against fungal phytopathogens for sustainable agriculture.
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Affiliation(s)
- Ajit Kumar Passari
- Molecular Microbiology and Systematic Laboratory, Department of Biotechnology, Aizawl, Mizoram University, Mizoram, 796004, India
| | - Vineet Kumar Mishra
- Molecular Microbiology and Systematic Laboratory, Department of Biotechnology, Aizawl, Mizoram University, Mizoram, 796004, India
| | - Vijai Kumar Gupta
- Molecular Glyco-biotechnology Group, Department of Biochemistry, National University of Ireland Galway, Galway, Ireland
| | - Mukesh Kumar Yadav
- Korea University college of Medicine, Korea University, Seoul, South Korea
| | - Ratul Saikia
- Biotechnology Division, CSIR-North East Institute of Science & Technology, Jorhat, 785006, Assam, India
| | - Bhim Pratap Singh
- Molecular Microbiology and Systematic Laboratory, Department of Biotechnology, Aizawl, Mizoram University, Mizoram, 796004, India
- * E-mail:
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Wang XM, Yang B, Ren CG, Wang HW, Wang JY, Dai CC. Involvement of abscisic acid and salicylic acid in signal cascade regulating bacterial endophyte-induced volatile oil biosynthesis in plantlets of Atractylodes lancea. PHYSIOLOGIA PLANTARUM 2015; 153:30-42. [PMID: 24862990 DOI: 10.1111/ppl.12236] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Revised: 05/04/2014] [Accepted: 05/11/2014] [Indexed: 05/02/2023]
Abstract
The enormous biological diversity of endophytes, coupled with their potential to enhance the production of bioactive metabolites in plants, has driven research efforts focusing on endophytes. However, limited information is available on the impacts of bacterial endophytes on plant secondary metabolism and signaling pathways involved. This work showed that an endophytic Acinetobacter sp. ALEB16, capable of activating accumulation of plant volatile oils, also induced abscisic acid (ABA) and salicylic acid (SA) production in Atractylodes lancea. Pre-treatment of plantlets with biosynthetic inhibitors of ABA or SA blocked the bacterium-induced volatile production. ABA inhibitors suppressed not only the bacterium-induced volatile accumulation but also the induced ABA and SA generation; nevertheless, SA inhibitors did not significantly inhibit the induced ABA biosynthesis, implying that SA acted downstream of ABA production. These results were confirmed by observations that exogenous ABA and SA reversed the inhibition of bacterium-induced volatile accumulation by inhibitors. Transcriptional activities of genes in sesquiterpenoid biosynthesis also increased significantly with bacterium, ABA and SA treatments. Mevalonate pathway proved to be the main source of isopentenyldiphosphate for bacterium-induced sesquiterpenoids, as assessed in experiments using specific terpene biosynthesis inhibitors. These results suggest that Acinetobacter sp. acts as an endophytic elicitor to stimulate volatile biosynthesis of A. lancea via an ABA/SA-dependent pathway, thereby yielding additional insight into the interconnection between ABA and SA in biosynthesis-related signaling pathways.
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Affiliation(s)
- Xiao-Mi Wang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
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Hamedi J, Mohammadipanah F. Biotechnological application and taxonomical distribution of plant growth promoting actinobacteria. J Ind Microbiol Biotechnol 2014; 42:157-71. [PMID: 25410828 DOI: 10.1007/s10295-014-1537-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 11/06/2014] [Indexed: 11/25/2022]
Abstract
Plant growth promoting (PGP) bacteria are involved in various interactions known to affect plant fitness and soil quality, thereby increasing the productivity of agriculture and stability of soil. Although the potential of actinobacteria in antibiotic production is well-investigated, their capacity to enhance plant growth is not fully surveyed. Due to the following justifications, PGP actinobacteria (PGPA) can be considered as a more promising taxonomical group of PGP bacteria: (1) high numbers of actinobacteria per gram of soil and their filamentous nature, (2) genome dedicated to the secondary metabolite production (~5 to 10 %) is distinctively more than that of other bacteria and (3) number of plant growth promoter genera reported from actinobacteria is 1.3 times higher than that of other bacteria. Mechanisms by which PGPA contribute to the plant growth by association are: (a) enhancing nutrients availability, (b) regulation of plant metabolism, (c) decreasing environmental stress, (d) control of phytopathogens and (e) improvement of soil texture. Taxonomical and chemical diversity of PGPA and their biotechnological application along with their associated challenges are summarized in this paper.
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Affiliation(s)
- Javad Hamedi
- Department of Microbial Biotechnology, School of Biology and Center of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, 14155-6455, Tehran, Iran,
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Brader G, Compant S, Mitter B, Trognitz F, Sessitsch A. Metabolic potential of endophytic bacteria. Curr Opin Biotechnol 2014; 27:30-7. [PMID: 24863894 PMCID: PMC4045207 DOI: 10.1016/j.copbio.2013.09.012] [Citation(s) in RCA: 266] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 09/22/2013] [Accepted: 09/27/2013] [Indexed: 11/30/2022]
Abstract
The bacterial endophytic microbiome promotes plant growth and health and beneficial effects are in many cases mediated and characterized by metabolic interactions. Recent advances have been made in regard to metabolite production by plant microsymbionts showing that they may produce a range of different types of metabolites. These substances play a role in defense and competition, but may also be needed for specific interaction and communication with the plant host. Furthermore, few examples of bilateral metabolite production are known and endophytes may modulate plant metabolite synthesis as well. We have just started to understand such metabolic interactions between plants and endophytes, however, further research is needed to more efficiently make use of beneficial plant-microbe interactions and to reduce pathogen infestation as well as to reveal novel bioactive substances of commercial interest.
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Affiliation(s)
- Günter Brader
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Strasse 24, 3430 Tulln, Austria
| | - Stéphane Compant
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Strasse 24, 3430 Tulln, Austria
| | - Birgit Mitter
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Strasse 24, 3430 Tulln, Austria
| | - Friederike Trognitz
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Strasse 24, 3430 Tulln, Austria
| | - Angela Sessitsch
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Strasse 24, 3430 Tulln, Austria.
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Knudsmark Jessing K, Duke SO, Cedergreeen N. Potential ecological roles of artemisinin produced by Artemisia annua L. J Chem Ecol 2014; 40:100-17. [PMID: 24500733 DOI: 10.1007/s10886-014-0384-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 10/16/2013] [Accepted: 01/21/2014] [Indexed: 11/24/2022]
Abstract
Artemisia annua L. (annual wormwood, Asteraceae) and its secondary metabolite artemisinin, a unique sesquiterpene lactone with an endoperoxide bridge, has gained much attention due to its antimalarial properties. Artemisinin has a complex structure that requires a significant amount of energy for the plant to synthesize. So, what are the benefits to A. annua of producing this unique compound, and what is the ecological role of artemisinin? This review addresses these questions, discussing evidence of the potential utility of artemisinin in protecting the plant from insects and other herbivores, as well as pathogens and competing plant species. Abiotic factors affecting the artemisinin production, as well as mechanisms of artemisinin release to the surroundings also are discussed, and new data are provided on the toxicity of artemisinin towards soil and aquatic organisms. The antifungal and antibacterial effects reported are not very pronounced. Several studies have reported that extracts of A. annua have insecticidal effects, though few studies have proven that artemisinin could be the single compound responsible for the observed effects. However, the pathogen(s) or insect(s) that may have provided the selection pressure for the evolution of artemisinin synthesis may not have been represented in the research thus far conducted. The relatively high level of phytotoxicity of artemisinin in soil indicates that plant/plant allelopathy could be a beneficial function of artemisinin to the producing plant. The release routes of artemisinin (movement from roots and wash off from leaf surfaces) from A. annua to the soil support the rationale for allelopathy.
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Affiliation(s)
- Karina Knudsmark Jessing
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark,
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