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Raio A. Diverse roles played by "Pseudomonas fluorescens complex" volatile compounds in their interaction with phytopathogenic microrganims, pests and plants. World J Microbiol Biotechnol 2024; 40:80. [PMID: 38281212 PMCID: PMC10822798 DOI: 10.1007/s11274-023-03873-0] [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: 09/29/2023] [Accepted: 12/15/2023] [Indexed: 01/30/2024]
Abstract
Pseudomonas fluorescens complex consists of environmental and some human opportunistic pathogenic bacteria. It includes mainly beneficial and few phytopathogenic species that are common inhabitants of soil and plant rhizosphere. Many members of the group are in fact known as effective biocontrol agents of plant pathogens and as plant growth promoters and for these attitudes they are of great interest for biotechnological applications. The antagonistic activity of fluorescent Pseudomonas is mainly related to the production of several antibiotic compounds, lytic enzymes, lipopeptides and siderophores. Several volatile organic compounds are also synthesized by fluorescent Pseudomonas including different kinds of molecules that are involved in antagonistic interactions with other organisms and in the induction of systemic responses in plants. This review will mainly focus on the volatile compounds emitted by some members of P. fluorescens complex so far identified, with the aim to highlight the role played by these molecules in the interaction of the bacteria with phytopathogenic micro and macro-organisms and plants.
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Affiliation(s)
- Aida Raio
- National Research Council, Institute for Sustainable Plant Protection (CNR-IPSP), Via Madonna del Piano, 10., 50019, Sesto Fiorentino, FI, Italy.
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Benchlih S, Esmaeel Q, Aberkani K, Tahiri A, Belabess Z, Lahlali R, Barka EA. Modes of Action of Biocontrol Agents and Elicitors for sustainable Protection against Bacterial Canker of Tomato. Microorganisms 2023; 11:microorganisms11030726. [PMID: 36985299 PMCID: PMC10054590 DOI: 10.3390/microorganisms11030726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/05/2023] [Accepted: 03/08/2023] [Indexed: 03/16/2023] Open
Abstract
Tomato is one of the world’s most commonly grown and consumed vegetables. However, it can be attacked by the Gram-positive bacterium Clavibacter michiganensis subsp. michiganensis (Cmm), which causes bacterial canker on tomato plants, resulting in significant financial losses in field production and greenhouses worldwide. The current management strategies rely principally on the application of various chemical pesticides and antibiotics, which represent a real danger to the environment and human safety. Plant growth-promoting rhizobacteria (PGPR) have emerged as an attractive alternative to agrochemical crop protection methods. PGPR act through several mechanisms to support plant growth and performance, while also preventing pathogen infection. This review highlights the importance of bacterial canker disease and the pathogenicity of Cmm. We emphasize the application of PGPR as an ecological and cost-effective approach to the biocontrol of Cmm, specifying the complex modes of biocontrol agents (BCAs), and presenting their direct/indirect mechanisms of action that enable them to effectively protect tomato crops. Pseudomonas and Bacillus are considered to be the most interesting PGPR species for the biological control of Cmm worldwide. Improving plants’ innate defense mechanisms is one of the main biocontrol mechanisms of PGPR to manage bacterial canker and to limit its occurrence and gravity. Herein, we further discuss elicitors as a new management strategy to control Cmm, which are found to be highly effective in stimulating the plant immune system, decreasing disease severity, and minimizing pesticide use.
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Affiliation(s)
- Salma Benchlih
- Phytopathology Unit, Department of Plant Protection, Ecole Nationale d’Agriculture de Meknès, Km 10, Rte Haj Kaddour, BP S/40, Meknes 50001, Morocco
- Unité de Recherche Résistance Induite et Bio-Protection des Plantes-EA 4707-USC INRAE1488, Université de Reims Champagne-Ardenne, 51100 Reims, France
- Faculté Poly-Disciplinaire de Nador, University Mohammed Premier, Oujda 60000, Morocco
| | - Qassim Esmaeel
- Unité de Recherche Résistance Induite et Bio-Protection des Plantes-EA 4707-USC INRAE1488, Université de Reims Champagne-Ardenne, 51100 Reims, France
| | - Kamal Aberkani
- Faculté Poly-Disciplinaire de Nador, University Mohammed Premier, Oujda 60000, Morocco
| | - Abdessalem Tahiri
- Phytopathology Unit, Department of Plant Protection, Ecole Nationale d’Agriculture de Meknès, Km 10, Rte Haj Kaddour, BP S/40, Meknes 50001, Morocco
| | - Zineb Belabess
- Plant Protection Laboratory, Regional Center of Agricultural Research of Meknes, National Institute of Agricultural Research, Km 13, Route Haj Kaddour, BP.578, Meknes 50001, Morocco
| | - Rachid Lahlali
- Phytopathology Unit, Department of Plant Protection, Ecole Nationale d’Agriculture de Meknès, Km 10, Rte Haj Kaddour, BP S/40, Meknes 50001, Morocco
- Correspondence: (R.L.); (E.A.B.)
| | - Essaid Ait Barka
- Unité de Recherche Résistance Induite et Bio-Protection des Plantes-EA 4707-USC INRAE1488, Université de Reims Champagne-Ardenne, 51100 Reims, France
- Correspondence: (R.L.); (E.A.B.)
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Villar-Moreno R, Tienda S, Gutiérrez-Barranquero JA, Carrión VJ, de Vicente A, Cazorla FM, Arrebola E. Interplay between rhizospheric Pseudomonas chlororaphis strains lays the basis for beneficial bacterial consortia. FRONTIERS IN PLANT SCIENCE 2022; 13:1063182. [PMID: 36589057 PMCID: PMC9797978 DOI: 10.3389/fpls.2022.1063182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 11/24/2022] [Indexed: 06/17/2023]
Abstract
Pseudomonas chlororaphis (Pc) representatives are found as part of the rhizosphere-associated microbiome, and different rhizospheric Pc strains frequently perform beneficial activities for the plant. In this study we described the interactions between the rhizospheric Pc strains PCL1601, PCL1606 and PCL1607 with a focus on their effects on root performance. Differences among the three rhizospheric Pc strains selected were first observed in phylogenetic studies and confirmed by genome analysis, which showed variation in the presence of genes related to antifungal compounds or siderophore production, among others. Observation of the interactions among these strains under lab conditions revealed that PCL1606 has a better adaptation to environments rich in nutrients, and forms biofilms. Interaction experiments on plant roots confirmed the role of the different phenotypes in their lifestyle. The PCL1606 strain was the best adapted to the habitat of avocado roots, and PCL1607 was the least, and disappeared from the plant root scenario after a few days of interaction. These results confirm that 2 out 3 rhizospheric Pc strains were fully compatible (PCL1601 and PCL1606), efficiently colonizing avocado roots and showing biocontrol activity against the fungal pathogen Rosellinia necatrix. The third strain (PCL1607) has colonizing abilities when it is alone on the root but displayed difficulties under the competition scenario, and did not cause deleterious effects on the other Pc competitors when they were present. These results suggest that strains PCL1601 and PCL1606 are very well adapted to the avocado root environment and could constitute a basis for constructing a more complex beneficial microbial synthetic community associated with avocado plant roots.
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Affiliation(s)
- Rafael Villar-Moreno
- Mango and Avocado Microbiology Group, Department of Microbiology, Faculty of Sciences, University of Málaga, Málaga, Spain
- Department of Microbiology and Plant Protection, Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
| | - Sandra Tienda
- Mango and Avocado Microbiology Group, Department of Microbiology, Faculty of Sciences, University of Málaga, Málaga, Spain
- Department of Microbiology and Plant Protection, Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
| | - Jose A. Gutiérrez-Barranquero
- Mango and Avocado Microbiology Group, Department of Microbiology, Faculty of Sciences, University of Málaga, Málaga, Spain
- Department of Microbiology and Plant Protection, Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
| | - Víctor J. Carrión
- Mango and Avocado Microbiology Group, Department of Microbiology, Faculty of Sciences, University of Málaga, Málaga, Spain
- Department of Microbiology and Plant Protection, Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
| | - Antonio de Vicente
- Mango and Avocado Microbiology Group, Department of Microbiology, Faculty of Sciences, University of Málaga, Málaga, Spain
- Department of Microbiology and Plant Protection, Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
| | - Francisco M. Cazorla
- Mango and Avocado Microbiology Group, Department of Microbiology, Faculty of Sciences, University of Málaga, Málaga, Spain
- Department of Microbiology and Plant Protection, Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
| | - Eva Arrebola
- Mango and Avocado Microbiology Group, Department of Microbiology, Faculty of Sciences, University of Málaga, Málaga, Spain
- Department of Microbiology and Plant Protection, Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, IHSM-UMA-CSIC, Málaga, Spain
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Plant Growth-Promoting Activity of Pseudomonas aeruginosa FG106 and Its Ability to Act as a Biocontrol Agent against Potato, Tomato and Taro Pathogens. BIOLOGY 2022; 11:biology11010140. [PMID: 35053136 PMCID: PMC8773043 DOI: 10.3390/biology11010140] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/31/2021] [Accepted: 01/10/2022] [Indexed: 12/24/2022]
Abstract
P. aeruginosa strain FG106 was isolated from the rhizosphere of tomato plants and identified through morphological analysis, 16S rRNA gene sequencing, and whole-genome sequencing. In vitro and in vivo experiments demonstrated that this strain could control several pathogens on tomato, potato, taro, and strawberry. Volatile and non-volatile metabolites produced by the strain are known to adversely affect the tested pathogens. FG106 showed clear antagonism against Alternaria alternata, Botrytis cinerea, Clavibacter michiganensis subsp. michiganensis, Phytophthora colocasiae, P. infestans, Rhizoctonia solani, and Xanthomonas euvesicatoria pv. perforans. FG106 produced proteases and lipases while also inducing high phosphate solubilization, producing siderophores, ammonia, indole acetic acid (IAA), and hydrogen cyanide (HCN) and forming biofilms that promote plant growth and facilitate biocontrol. Genome mining approaches showed that this strain harbors genes related to biocontrol and growth promotion. These results suggest that this bacterial strain provides good protection against pathogens of several agriculturally important plants via direct and indirect modes of action and could thus be a valuable bio-control agent.
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Castaldi S, Masi M, Sautua F, Cimmino A, Isticato R, Carmona M, Tuzi A, Evidente A. Pseudomonas fluorescens Showing Antifungal Activity against Macrophomina phaseolina, a Severe Pathogenic Fungus of Soybean, Produces Phenazine as the Main Active Metabolite. Biomolecules 2021; 11:1728. [PMID: 34827726 PMCID: PMC8615785 DOI: 10.3390/biom11111728] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 11/11/2021] [Accepted: 11/17/2021] [Indexed: 01/03/2023] Open
Abstract
Pseudomonas fluorescens 9 and Bacillus subtilis 54, proposed as biofungicides to control Macrophomina phaseolina, a dangerous pathogen of soybean and other crops, were grown in vitro to evaluate their ability to produce metabolites with antifungal activity. The aim of the manuscript was to identify the natural compounds responsible for their antifungal activity. Only the culture filtrates of P. fluorescens 9 showed strong antifungal activity against M. phaseolina. Its organic extract contained phenazine and mesaconic acid (1 and 2), whose antifungal activity was tested against M. phaseolina, as well as Cercospora nicotianae and Colletotrichum truncatum, other pathogens of soybean; however, only compound 1 exhibited activity. The antifungal activity of compound 1 was compared to phenazine-1-carboxylic acid (PCA, 3), 2-hydroxyphenazine (2-OH P, 4), and various semisynthetic phenazine nitro derivatives in order to perform a structure-activity relationship (SAR) study. PCA and phenazine exhibited the same percentage of growth inhibition in M. phaseolina and C. truncatum, whereas PCA (3) showed lower activity against C. nicotianae than phenazine. 2-Hydroxyphenazine (4) showed no antifungal activity against M. phaseolina. The results of the SAR study showed that electron attractor (COOH and NO2) or repulsor (OH) groups significantly affect the antifungal growth, as well as their α- or β-location on the phenazine ring. Both PCA and phenazine could be proposed as biopesticides to control the soybean pathogens M. phaseolina, C. nicotianae, and C. truncatum, and these results should prompt an investigation of their large-scale production and their suitable formulation for greenhouse and field applications.
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Affiliation(s)
- Stefany Castaldi
- Dipartimento di Biologia, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy;
| | - Marco Masi
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy; (M.M.); (A.C.); (A.T.); (A.E.)
| | - Francisco Sautua
- Cátedra de Fitopatología, Facultad de Agronomía, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires C1417DSE, Argentina; (F.S.); (M.C.)
| | - Alessio Cimmino
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy; (M.M.); (A.C.); (A.T.); (A.E.)
| | - Rachele Isticato
- Dipartimento di Biologia, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy;
| | - Marcelo Carmona
- Cátedra de Fitopatología, Facultad de Agronomía, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires C1417DSE, Argentina; (F.S.); (M.C.)
| | - Angela Tuzi
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy; (M.M.); (A.C.); (A.T.); (A.E.)
| | - Antonio Evidente
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy; (M.M.); (A.C.); (A.T.); (A.E.)
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Cimmino A, Bahmani Z, Castaldi S, Masi M, Isticato R, Abdollahzadeh J, Amini J, Evidente A. Phenazine-1-Carboxylic Acid (PCA), Produced for the First Time as an Antifungal Metabolite by Truncatella angustata, a Causal Agent of Grapevine Trunk Diseases (GTDs) in Iran. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:12143-12147. [PMID: 34623150 PMCID: PMC8532150 DOI: 10.1021/acs.jafc.1c03877] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 09/15/2021] [Accepted: 09/28/2021] [Indexed: 06/13/2023]
Abstract
The phytopathogenic fungus Truncatella angustata, associated with grapevine trunk diseases (GTDs) in Iran, produces the well-known secondary metabolite isocoumumarin (+)-6-hyroxyramulosin and surprisingly also phenazine-1-carboxylic acid (PCA). PCA, identified by spectroscopic (essentially 1H NMR and ESI MS) spectra, is a bacterial metabolite well known for its antifungal activity and was found for the first time in T. angustata culture filtrates. The antifungal activity of PCA was assayed against four different fungi responsible for GTDs, Phaeoacremonium minimum, Phaeoacremonium italicum, Fomitiporia mediterranea, involved in grapevine esca disease, and Neofusicoccum parvum, responsible for Botryosphaeria dieback. The activity was compared with that of the known commercial fungicide, pentachloronitrobenzene, and the close phenazine. PCA and phenazine exhibited strong antifungal activity against all phytopathogenic fungi, inhibiting the fungal growth by about 90-100% and 80-100%, respectively. These results suggested that T. angustata could use PCA to compete with other phytopathogenic fungi that attack grapevine and thus PCA could be proposed as a biofungicide against the fungi responsible for grapevine esca and Botryosphaeria dieback diseases.
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Affiliation(s)
- Alessio Cimmino
- Department
of Chemical Sciences, University of Naples
Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Zeinab Bahmani
- Department
of Plant Protection, Agriculture Faculty, University of Kurdistan, P.O. Box 416 Sanandaj, Iran
| | - Stefany Castaldi
- Department
of Biology, University of Naples Federico
II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Marco Masi
- Department
of Chemical Sciences, University of Naples
Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Rachele Isticato
- Department
of Biology, University of Naples Federico
II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Jafar Abdollahzadeh
- Department
of Plant Protection, Agriculture Faculty, University of Kurdistan, P.O. Box 416 Sanandaj, Iran
| | - Jahanshir Amini
- Department
of Plant Protection, Agriculture Faculty, University of Kurdistan, P.O. Box 416 Sanandaj, Iran
| | - Antonio Evidente
- Department
of Chemical Sciences, University of Naples
Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
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Zdorovenko EL, Dmitrenok AS, Masi M, Castaldi S, Muzio FM, Isticato R, Valverde C, Knirel YA, Evidente A. Structural studies on the O-specific polysaccharide of the lipopolysaccharide from Pseudomonas donghuensis strain SVBP6, with antifungal activity against the phytopathogenic fungus Macrophomina phaseolina. Int J Biol Macromol 2021; 182:2019-2023. [PMID: 34081955 DOI: 10.1016/j.ijbiomac.2021.05.187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/30/2021] [Accepted: 05/26/2021] [Indexed: 12/27/2022]
Abstract
An O-specific polysaccharide (OPS) was isolated from the lipopolysaccharide (LPS) of Pseudomonas donghuensis SVBP6, a bacterium with a broad-spectrum antifungal activity in vitro, particularly that against Macrophomina phaseolina. This latter is one of the most virulent and dangerous pathogens of plants, including soybean which is an economically important crop in Argentina today. The OPS was studied by sugar analysis and spectroscopy (1D and 2D 1H and 13C NMR) showing the following trisaccharide repeating unit: →6)-ɑ-D-ManpNAc-(1 → 3)-β-l-Rhap-(1 → 4)-β-D-Glcp-(1→. The crude LPS, the purified LPS and the O-chain were assayed for their antifungal activity against M. phaseolina at 25, 50, 100, and 200 μg plug-1. The results showed that the crude LPS best inhibition was at 200 μg plug-1, able to inhibit the fungus growth by about 45%, while purified LPS and the corresponding OPS, in the same condition, reduced fungus growth by 65%, and 75%, respectively. Furthermore, the purified LPS and OPS significantly reduced the growth of M. phaseolina already at 100 μg plug-1 compared to the crude LPS. The structure of the O-chain is unique among the bacterial LPS and this is the first time that both the antifungal activity of a bacterial LPS and its corresponding O-chain were described.
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Affiliation(s)
- Evelina L Zdorovenko
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospekt 47, 119991 Moscow, Russia
| | - Andrey S Dmitrenok
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospekt 47, 119991 Moscow, Russia
| | - Marco Masi
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy
| | - Stefany Castaldi
- Department of Biology, University of Naples Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy
| | - Federico M Muzio
- Laboratorio de Fisiología y Genética de Bacterias Beneficiosas para Plantas-Centro de Bioquímica y Microbiología del Suelo, Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes-CONICET, Buenos Aires, Argentina
| | - Rachele Isticato
- Department of Biology, University of Naples Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy
| | - Claudio Valverde
- Laboratorio de Fisiología y Genética de Bacterias Beneficiosas para Plantas-Centro de Bioquímica y Microbiología del Suelo, Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes-CONICET, Buenos Aires, Argentina
| | - Yuriy A Knirel
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospekt 47, 119991 Moscow, Russia
| | - Antonio Evidente
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy.
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Raio A, Puopolo G. Pseudomonas chlororaphis metabolites as biocontrol promoters of plant health and improved crop yield. World J Microbiol Biotechnol 2021; 37:99. [PMID: 33978868 DOI: 10.1007/s11274-021-03063-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 04/23/2021] [Indexed: 11/28/2022]
Abstract
The Pseudomonas fluorescens complex contains at least eight phylogenetic groups and each of these includes several bacterial species sharing ecological and physiological traits. Pseudomonas chlororaphis classified in a separate group is represented by three different subspecies that show distinctive traits exploitable for phytostimulation and biocontrol of phytopathogens. The high level of microbial competitiveness in soil as well as the effectiveness in controlling several plant pathogens and pests can be related to the P. chlororaphis ability to implement different stimulating and toxic mechanisms in its interaction with plants and the other micro- and macroorganisms. Pseudomonas chlororaphis strains produce antibiotics, such as phenazines, pyrrolnitrine, 2-hexyl, 5-propyl resorcinol and hydrogen cyanide, siderophores such as pyoverdine and achromobactine and a complex blend of volatile organic compounds (VOCs) that effectively contribute to the control of several plant pathogens, nematodes and insects. Phenazines and some VOCs are also involved in the induction of systemic resistance in plants. This complex set of beneficial strategies explains the high increasing interest in P. chlororaphis for commercial and biotechnological applications. The aim of this review is to highlight the role of the different mechanisms involved in the biocontrol activity of P. chlororaphis strains.
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Affiliation(s)
- Aida Raio
- Institute for Sustainable Plant Protection, National Research Council, Sesto Fiorentino, FI, Italy.
| | - Gerardo Puopolo
- Center Agriculture Food Environment C3A, University of Trento/Fondazione Edmund Mach, San Michele all'Adige, TN, Italy.,Department of Sustainable Agro-Ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, TN, Italy
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Elucidation and Identification of an Antifungal Compound from Pseudomonas aeruginosa DA3.1 Isolated from Soil in Vietnam. Jundishapur J Microbiol 2020. [DOI: 10.5812/jjm.103792] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background: Fusarium sp. and Rhizoctonia sp. fungi have been always threats to short-term crops. In Vietnam, corn and soybean suffer serious losses annually. Therefore, it is necessary to utilize an environmentally friendly antifungal compound that is highly effective against phytopathogenic fungi. Pseudomonas sp. is a popular soil bacterial strain and well known for its high antifungal activity. Objectives: This study was carried out to evaluate and assess the antifungal activity of a local bacterial strain namely DA3.1 that was later identified as Pseudomonas aeruginosa. This would be strong scientific evidence to develop an environmentally friendly biocide from a local microorganism strain for commercial use. Methods: The antifungal compound was purified from ethyl acetate extraction of deproteinized cell culture broth by a silica gel column (CH2Cl2/MeOH (0% - 10% MeOH)). The purity of the isolated compound was determined by HPLC, and its molecular structure was elucidated using spectroscopic experiments including one-dimensional (1D) (1H NMR, 13C NMR, DEPT) and two-dimensional (2D) (HMBC and HSQC) spectra. The activity of the purified compound against Fusarium sp. and Rhizoctonia sp. fungi was measured using the PDA-disk diffusion method, and its growth-promoting ability was evaluated using the seed germination test of corn and soybean. Results: The results showed that the antifungal compound produced by Pseudomonas aeruginosa DA3.1 had a retention factor (Rf) of 0.86 on thin layer chromatography (TLC). Based on the evidence of spectral data including proton nuclear magnetic resonance (1H NMR), carbon nuclear magnetic resonance (13C NMR), distortionless enhancement by polarization transfer (DEPT), heteronuclear multiple bond correlation (HMBC), and heteronuclear single quantum coherence (HSQC), the chemical structure was elucidated as phenazine-1-carboxylic. The purified compound showed inhibitory activity against F. oxysporum and R. solani and exhibited the ability of the germination of corn and soybean seeds. The results revealed the benefit of native P. aeruginosa DA3.1 and phenazine-1-carboxylic acid for use as a biocontrol agent, as well as a plant growth promoter. Conclusions: The antifungal compound isolated from local Pseudomonas DA3.1 was identified as phenazine-1-carboxylic acid that posed high antifungal activity and was a plant germination booster.
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Raio A, Brilli F, Baraldi R, Neri L, Puopolo G. Impact of spontaneous mutations on physiological traits and biocontrol activity of Pseudomonas chlororaphis M71. Microbiol Res 2020; 239:126517. [PMID: 32535393 DOI: 10.1016/j.micres.2020.126517] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 05/06/2020] [Accepted: 05/13/2020] [Indexed: 10/24/2022]
Abstract
Three morphological mutants (M71a, M71b, M71c) of the antagonist Pseudomonas chlororaphis M71, naturally arose during a biocontrol trial against the phytopathogenic fungus Fusarium oxysporum f.sp. radicis-lycopersisci. In this study, the three mutants were investigated to elucidate their role in the biocontrol of plant pathogens. M71a and M71b phenotypes were generated by a mutation in the two-component system GacS/GacA. The mutation determined an increase in siderophore production and an impaired ability to release proteases, to swarm, to produce phenazine and AHLs and to colonize tomato roots. In vitro antagonistic activity against different plant pathogens was partially reduced in M71a, while M71b resulted effective only against Pythium ultimum. Biocontrol efficacy against Fusarium oxysporum f.sp. radicis-lycopersisci, was partially reduced in M71a and completely lost in M71b. M71c phenotype was impaired in swarming motility, did not produce biofilms and its antagonistic activity was similar to the parental M71 strain. M71c showed an enhanced ability to colonize tomato roots, on which its progeny in part reverted to the M71 parental phenotype. Volatile organic compounds (VOCs) emitted by all four strains, inhibited the growth of Clavibacter michiganensis subsp. michiganensis and Seiridium cardinale in vitro. Real-time screening of VOCs by PTR-MS combined with GC-MS analysis, showed that methanethiol was the main component of the blend produced by all four M71 strains. However, the emissions of hydrogen cyanide, dimethyl disulfide, 1,3-butadiene and acetone were significantly affected by the three different mutations. These findings highlight that the simultaneous presence of different M71 phenotypes may improve, through the integration of different mechanisms, the ecological fitness and biocontrol efficacy of P. chlororaphis M71.
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Affiliation(s)
- Aida Raio
- Institute for Sustainable Plant Protection, National Research Council, Via Madonna del Piano 10, 50019, Sesto Fiorentino, FI, Italy.
| | - Federico Brilli
- Institute for Sustainable Plant Protection, National Research Council, Via Madonna del Piano 10, 50019, Sesto Fiorentino, FI, Italy
| | - Rita Baraldi
- Institute of BioEconomy, National Research Council, Bologna, Italy
| | - Luisa Neri
- Center Agriculture Food Environment (C3A), University of Trento, via E. Mach 1, San Michele all'Adige, 38010, Italy
| | - Gerardo Puopolo
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, San Michele all'Adige, 38010, Italy
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11
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Proteolytic, Lipolytic and Amylolytic Bacteria Reservoir of Turkey; Cold-Adaptive Bacteria in Detergent Industry. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2020. [DOI: 10.22207/jpam.14.1.09] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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12
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Janakiev T, Dimkić I, Unković N, Ljaljević Grbić M, Opsenica D, Gašić U, Stanković S, Berić T. Phyllosphere Fungal Communities of Plum and Antifungal Activity of Indigenous Phenazine-Producing Pseudomonas synxantha Against Monilinia laxa. Front Microbiol 2019; 10:2287. [PMID: 31632384 PMCID: PMC6779809 DOI: 10.3389/fmicb.2019.02287] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 09/19/2019] [Indexed: 12/21/2022] Open
Abstract
European plum (Prunus domestica L.) is a significant commercial crop in Serbia in terms of total fruit production, and is traditionally processed into slivovitz brandy. The brown rot disease caused by Monilinia laxa drastically reduces plum yield almost every year. Fungal communities associated with leaves and fruits of four local Serbian plum cultivars (Požegača, Ranka, Čačanska Lepotica and Čačanska Rodna) were investigated in two phenological stages during early (May) and late (July) fruit maturation. Alpha diversity indices showed that fungal communities were heterogeneous and Beta diversity indicated that autochthonous fungal communities depended upon seasonal changes and the cultivars themselves. The phylum Ascomycota was the most abundant in all samples, with relative abundance (RA) between 46% in the Požegača cultivar (May) and 89% in the Lepotica cultivar (July). The most abundant genus for all plum cultivars in May was Aureobasidium, with RA from 19.27 to 33.69%, followed by Cryptococcus, with 4.8 to 48.80%. In July, besides Cryptococcus, different genera (Metschnikowia, Fusarium, and Hanseniaspora) were dominant on particular cultivars. Among all cultivable fungi, molecular identification of eleven M. laxa isolates from four plum cultivars was performed simultaneously. Bacterial isolates from the plum phyllosphere were tested for their potential antifungal activity against indigenous M. laxa isolates. The most potent antagonist P4/16_1, which significantly reduced mycelial growth of M. laxa, was identified as Pseudomonas synxantha. Further characterization of P4/16_1 revealed the production of volatile organic compounds and phenazine-1-carboxylic acid (PCA). Crude benzene extract of PCA exhibited 57-63% mycelial growth inhibition of M. laxa. LC/MS analysis of the crude extract confirmed the presence of phenazine derivatives amongst other compounds. Scanning electron microscopy revealed morpho-physiological changes in the hyphae of M. laxa isolates caused by the cell culture and the P. synxantha P4/16_1 crude benzene extract. This is the first report of antagonistic activity of P. synxantha against M. laxa induced by diffusible and volatile antifungal compounds, and it appears to be a promising candidate for further investigation for potential use as a biocontrol agent against brown rot-causing fungi.
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Affiliation(s)
- Tamara Janakiev
- Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Ivica Dimkić
- Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Nikola Unković
- Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | | | - Dejan Opsenica
- Institute of Chemistry, Technology and Metallurgy, University of Belgrade, Belgrade, Serbia
| | - Uroš Gašić
- Faculty of Chemistry, University of Belgrade, Belgrade, Serbia
| | | | - Tanja Berić
- Faculty of Biology, University of Belgrade, Belgrade, Serbia
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13
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Arrebola E, Tienda S, Vida C, de Vicente A, Cazorla FM. Fitness Features Involved in the Biocontrol Interaction of Pseudomonas chlororaphis With Host Plants: The Case Study of PcPCL1606. Front Microbiol 2019; 10:719. [PMID: 31024497 PMCID: PMC6469467 DOI: 10.3389/fmicb.2019.00719] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 03/21/2019] [Indexed: 12/31/2022] Open
Abstract
The goal of this mini review is to summarize the relevant contribution of some beneficial traits to the behavior of the species Pseudomonas chlororaphis, and using that information, to give a practical point of view using the model biocontrol strain P. chlororaphis PCL1606 (PcPCL1606). Among the group of plant-beneficial rhizobacteria, P. chlororaphis has emerged as a plant- and soil-related bacterium that is mainly known because of its biological control of phytopathogenic fungi. Many traits have been reported to be crucial during the multitrophic interaction involving the plant, the fungal pathogen and the soil environment. To explore the different biocontrol-related traits, the biocontrol rhizobacterium PcPCL1606 has been used as a model in recent studies. This bacterium is antagonistic to many phytopathogenic fungi and displays effective biocontrol against fungal phytopathogens. Antagonistic and biocontrol activities are directly related to the production of the compound 2-hexyl, 5-propyl resorcinol (HPR), despite the production of other antifungal compounds. Furthermore, PcPCL1606 has displayed additional traits regarding its fitness in soil and plant root environments such as soil survival, efficient plant root colonization, cell-to-cell interaction or promotion of plant growth.
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Affiliation(s)
- Eva Arrebola
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora" IHSM, UMA-CSIC, Málaga, Spain
| | - Sandra Tienda
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora" IHSM, UMA-CSIC, Málaga, Spain
| | - Carmen Vida
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora" IHSM, UMA-CSIC, Málaga, Spain
| | - Antonio de Vicente
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora" IHSM, UMA-CSIC, Málaga, Spain
| | - Francisco M Cazorla
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora" IHSM, UMA-CSIC, Málaga, Spain
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14
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Zhang Y, Li T, Liu Y, Li X, Zhang C, Feng Z, Peng X, Li Z, Qin S, Xing K. Volatile Organic Compounds Produced by Pseudomonas chlororaphis subsp. aureofaciens SPS-41 as Biological Fumigants To Control Ceratocystis fimbriata in Postharvest Sweet Potatoes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:3702-3710. [PMID: 30860830 DOI: 10.1021/acs.jafc.9b00289] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The biocontrol activity and chemical composition of the volatile organic compounds (VOCs) produced by Pseudomonas chlororaphis subsp. aureofaciens SPS-41 were investigated. The VOCs inhibited mycelial growth and spore germination in Ceratocystis fimbriata, which causes black rot disease in sweet potato tuber roots (TRs) and showed wide-spectrum antifungal activity against several plant pathogenic fungi. A microscopic examination of C. fimbriata cells suggested morphological changes and a loss of cellular contents. Different inoculation strategies significantly affected the antifungal activity of the VOCs. In the volatile profile of SPS-41, the most abundant compound, 3-methyl-1-butanol, followed by phenylethyl alcohol and 2-methyl-1-butanol showed strong inhibition toward C. fimbriata. The weight loss rate and disease severity of the TRs were significantly reduced in response to the VOCs emitted by SPS-41. The results suggest that the VOCs produced by P. chlororaphis subsp. aureofaciens SPS-41 might constitute an attractive biological fumigant for controlling black rot disease in sweet potato TRs.
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Affiliation(s)
| | | | | | - Xiaoyan Li
- College of Life Sciences , Northeast Forestry University , Harbin 150040 , Heilongjiang , P.R. China
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15
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Calderón CE, Tienda S, Heredia-Ponce Z, Arrebola E, Cárcamo-Oyarce G, Eberl L, Cazorla FM. The Compound 2-Hexyl, 5-Propyl Resorcinol Has a Key Role in Biofilm Formation by the Biocontrol Rhizobacterium Pseudomonas chlororaphis PCL1606. Front Microbiol 2019; 10:396. [PMID: 30873149 PMCID: PMC6403133 DOI: 10.3389/fmicb.2019.00396] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 02/14/2019] [Indexed: 11/13/2022] Open
Abstract
The production of the compound 2-hexyl-5-propyl resorcinol (HPR) by the biocontrol rhizobacterium Pseudomonas chlororaphis PCL1606 (PcPCL1606) is crucial for fungal antagonism and biocontrol activity that protects plants against the phytopathogenic fungus Rosellinia necatrix. The production of HPR is also involved in avocado root colonization during the biocontrol process. This pleiotrophic response prompted us to study the potential role of HPR production in biofilm formation. The swimming motility of PcPLL1606 is enhanced by the disruption of HPR production. Mutants impaired in HPR production, revealed that adhesion, colony morphology, and typical air–liquid interphase pellicles were all dependent on HPR production. The role of HPR production in biofilm architecture was also analyzed in flow chamber experiments. These experiments revealed that the HPR mutant cells had less tight unions than those producing HPR, suggesting an involvement of HPR in the production of the biofilm matrix.
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Affiliation(s)
- Claudia E Calderón
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," Consejo Superior de Investigaciones Científicas, Universidad de Málaga, IHSM-UMA-CSIC, Málaga, Spain
| | - Sandra Tienda
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," Consejo Superior de Investigaciones Científicas, Universidad de Málaga, IHSM-UMA-CSIC, Málaga, Spain
| | - Zaira Heredia-Ponce
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," Consejo Superior de Investigaciones Científicas, Universidad de Málaga, IHSM-UMA-CSIC, Málaga, Spain
| | - Eva Arrebola
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," Consejo Superior de Investigaciones Científicas, Universidad de Málaga, IHSM-UMA-CSIC, Málaga, Spain
| | | | - Leo Eberl
- Department of Plant and Microbial Biology, University of Zürich, Zurich, Switzerland
| | - Francisco M Cazorla
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora," Consejo Superior de Investigaciones Científicas, Universidad de Málaga, IHSM-UMA-CSIC, Málaga, Spain
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16
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Brilli F, Pollastri S, Raio A, Baraldi R, Neri L, Bartolini P, Podda A, Loreto F, Maserti BE, Balestrini R. Root colonization by Pseudomonas chlororaphis primes tomato (Lycopersicum esculentum) plants for enhanced tolerance to water stress. JOURNAL OF PLANT PHYSIOLOGY 2019; 232:82-93. [PMID: 30537616 DOI: 10.1016/j.jplph.2018.10.029] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 10/05/2018] [Accepted: 10/27/2018] [Indexed: 06/09/2023]
Abstract
Previous research demonstrated that Pseudomonas chlororaphis subsp. aureofaciens strain M71, a plant growth promoting bacterium (PGPB), exerts beneficial effects on plant metabolism and primes tolerance mechanisms against biotic stresses in tomatoes. We designed an experiment to assess whether root colonization with P. chlororaphis is also able to improve tolerance to water stress in tomatoes. Our results show that inoculation with P. chlororaphis stimulates the antioxidant activity of well-watered tomatoes while maintaining a steady-state level of reactive oxygen species (ROS), increases the expression of genes encoding for the biosynthesis of leaf terpenes, stimulates the production of both the phytohormones ABA and IAA, in turn affecting plant shape (number of leaves) and height (length of internodes), without altering photosynthesis. Upon exposure to mild water stress conditions, an improved antioxidant activity in tomatoes 'primed' by P. chlororaphis inoculation limited the accumulation of reactive oxygen species (ROS) in leaves and thus enhanced tolerance, also through increase of the (osmolyte) proline content. Moreover, P. chlororaphis inoculation further enhanced the ABA level in leaves of water-stressed tomatoes allowing a more efficient modulation of stomatal closure that resulted in an improved water use efficiency (WUE) and biomass accumulation.
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Affiliation(s)
- Federico Brilli
- National Research Council of Italy - Institute for Sustainable Plant Protection (CNR-IPSP), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy.
| | - Susanna Pollastri
- National Research Council of Italy - Institute for Sustainable Plant Protection (CNR-IPSP), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy
| | - Aida Raio
- National Research Council of Italy - Institute for Sustainable Plant Protection (CNR-IPSP), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy
| | - Rita Baraldi
- National Research Council of Italy - Institute of Biometeorology (CNR-IBIMET), via P. Gobetti 101, 40129 Bologna, Italy
| | - Luisa Neri
- National Research Council of Italy - Institute of Biometeorology (CNR-IBIMET), via P. Gobetti 101, 40129 Bologna, Italy
| | - Paola Bartolini
- National Research Council of Italy - Institute for Sustainable Plant Protection (CNR-IPSP), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy
| | - Alessandra Podda
- National Research Council of Italy - Institute for Sustainable Plant Protection (CNR-IPSP), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy
| | - Francesco Loreto
- National Research Council of Italy - Department of Biology, Agriculture and Food Sciences (CNR-DISBA), P. le Aldo Moro, 00185 Roma, Italy
| | - Bianca Elena Maserti
- National Research Council of Italy - Institute for Sustainable Plant Protection (CNR-IPSP), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy
| | - Raffaella Balestrini
- National Research Council of Italy - Institute for Sustainable Plant Protection (CNR-IPSP), Viale P.A. Mattioli 25, 10125 Torino, Italy
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17
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Kujawa M, Lirski M, Ziecina M, Drabinska J, Modzelan M, Kraszewska E. Nudix-type RNA pyrophosphohydrolase provides homeostasis of virulence factor pyocyanin and functions as a global regulator in Pseudomonas aeruginosa. Mol Microbiol 2017; 106:381-394. [PMID: 28833678 DOI: 10.1111/mmi.13771] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/11/2017] [Indexed: 12/26/2022]
Abstract
The PA0336 protein from Pseudomonas aeruginosa belongs to the family of widely distributed Nudix pyrophosphohydrolases, which catalyze the hydrolysis of pyrophosphate bonds in a variety of nucleoside diphosphate derivatives. The amino acid sequence of the PA0336 protein is highly similar to that of the RppH Nudix RNA pyrophosphohydrolase from Escherichia coli, which removes pyrophosphate from 5'-end of triphosphorylated RNA transcripts. Trans-complementation experiments showed that the P. aeruginosa enzyme can functionally substitute for RppH in E. coli cells indicating that, similar to RppH, the Pseudomonas hydrolase mediates RNA turnover in vivo. In order to elucidate the biological significance of the PA0336 protein in Pseudomonas cells, a PA0336 mutant strain was constructed. The mutated strain considerably increased level of the virulence factor pyocyanin compared to wild type, suggesting that PA0336 could be involved in downregulation of P. aeruginosa pathogenicity. This phenotype was reversed by complementation with the wild type but not catalytically inactive PA0336, indicating that the catalytic activity was indispensable for its biological function. Pathogenesis tests in Caenorhabditis elegans showed that the PA0336 mutant of P. aeruginosa was significantly more virulent than the parental strain, confirming further that the P. aeruginosa RNA pyrophosphohydrolase PA0336 modulates bacterial pathogenesis by down-regulating production of virulence-associated factors. To study the role of PA0336 further, transcriptomes of the PA0336 mutant and the wild-type strain were compared using RNA sequencing. The level of 537 transcripts coding for proteins involved in a variety of cellular processes such as replication, transcription, translation, central metabolism and pathogenesis, was affected by the lack of PA0336. These results indicate that the PA0336 RNA pyrophosphohydrolase functions as a global regulator that influences many of transcripts including those involved in P. aeruginosa virulence.
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Affiliation(s)
- Martyna Kujawa
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Maciej Lirski
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Mateusz Ziecina
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Joanna Drabinska
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Marta Modzelan
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Elzbieta Kraszewska
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
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