1
|
Jafra S, Jabłońska M, Maciąg T, Matuszewska M, Borowicz M, Prusiński M, Żmudzińska W, Thiel M, Czaplewska P, Krzyżanowska DM, Czajkowski R. An iron fist in a velvet glove: The cooperation of a novel pyoverdine from Pseudomonas donghuensis P482 with 7-hydroxytropolone is pivotal for its antibacterial activity. Environ Microbiol 2024; 26:e16559. [PMID: 38151794 DOI: 10.1111/1462-2920.16559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 12/06/2023] [Indexed: 12/29/2023]
Abstract
Pseudomonas donghuensis P482 exhibits broad antimicrobial activity against phytopathogens, including the soft rot bacteria of the Dickeya genus. Here, we report that under limited nutrient availability, the antibacterial activity of P. donghuensis P482 against Dickeya solani requires the reciprocal action of two iron scavengers: 7-hydroxytropolone (7-HT) and a newly characterized pyoverdine (PVDP482 ) and is quenched in the iron-augmented environment. Further, we show that the biosynthesis of pyoverdine and 7-HT is metabolically coordinated, and the functional BV82_4709 gene involved in 7-HT synthesis is pivotal for expressing the BV82_3755 gene, essential for pyoverdine biosynthesis and vice versa. The synthesis of both scavengers is under the control of Gac/Rsm, but only PVD is controlled by Fur. The isoelectric focusing profile of the P482 siderophore differs from that of the other Pseudomonas spp. tested. This finding led to the unveiling of the chemical structure of the new pyoverdine PVDP482 . To summarize, the antibacterial activity of P. donghuensis P482 is attributed to 7-HT and PVDP482 varies depending on the nutrient and iron availability, highlighting the importance of these factors in the competition between P482 and D. solani.
Collapse
Affiliation(s)
- Sylwia Jafra
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Magdalena Jabłońska
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Tomasz Maciąg
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Marta Matuszewska
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Marcin Borowicz
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Michał Prusiński
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Wioletta Żmudzińska
- Laboratory of Biopolymers Structure, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Marcel Thiel
- Laboratory of Biopolymers Structure, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Paulina Czaplewska
- Laboratory of Mass Spectrometry, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Dorota M Krzyżanowska
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Robert Czajkowski
- Laboratory of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology of the University of Gdansk and the Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| |
Collapse
|
2
|
Munier-Lépinay E, Mathiron D, Quéro A, Khelifa M, Laclef S, Pilard S. Pseudomonas PA14H7: Identification and Quantification of the 7-Hydroxytropolone Iron Complex as an Active Metabolite against Dickeya, the Causal Agent of Blackleg on the Potato Plant. Molecules 2023; 28:6207. [PMID: 37687036 PMCID: PMC10488565 DOI: 10.3390/molecules28176207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 09/10/2023] Open
Abstract
Soft rot Pectobacteriaceae (SRP), such as Pectobacterium and Dickeya, are phytopathogenic agents responsible for blackleg disease on several crops, such as potatoes, affecting the yield and depressing the seed production quality. However, neither conventional nor biocontrol products are available on the market to control this disease. In this study Pseudomonas PA14H7, a bacteria isolated from potato rhizosphere, was selected as a potential antagonist agent against Dickeya solani. In order to understand the mechanism involved in this antagonism, we managed to identify the main active molecule(s) produced by PA14H7. Cell-free supernatant (CFS) of PA14H7 cultures were extracted and analyzed using LC-MS, GC-MS, and NMR. We further correlated the biological activity against Dickeya solani of extracted CFS-PA14H7 to the presence of 7-hydroxytropolone (7-HT) complexed with iron. In a second time, we have synthesized this molecule and determined accurately using LC-UV, LC-MS, and GC-MS that, after 48 h incubation, PA14H7 released, in its CFS, around 9 mg/L of 7-HT. The biological activities of CFS-PA14H7 vs. synthetic 7-HT, at this concentration, were evaluated to have a similar bacteriostatic effect on the growth of Dickeya solani. Even if 7-HT is produced by other Pseudomonas species and is mostly known for its antibacterial and antifungal activities, this is the first description of its involvement as an effective molecule against pectinolytic bacteria. Our work opens the way for the comprehension of the mode of action of PA14H7 as a biocontrol agent against potato blackleg.
Collapse
Affiliation(s)
- Euphrasie Munier-Lépinay
- inov3PT—Recherche Développement Innovation des Producteurs de Plants de Pomme de Terre, 43-45 Rue de Naples, 75008 Paris, France; (E.M.-L.); (M.K.)
- Plateforme-Analytique (PFA), Institut de Chimie de Picardie FR 3085, Université de Picardie Jules Verne, 33 Rue Saint Leu, 80039 Amiens, France;
- Laboratoire de Glycochimie, des Antimicrobiens et des Agroressources (LG2A), Institut de Chimie de Picardie FR 3085, Université de Picardie Jules Verne, 33 Rue Saint Leu, 80039 Amiens, France
| | - David Mathiron
- Plateforme-Analytique (PFA), Institut de Chimie de Picardie FR 3085, Université de Picardie Jules Verne, 33 Rue Saint Leu, 80039 Amiens, France;
| | - Anthony Quéro
- UMRT INRAE 1158 BioEcoAgro, UFR de Pharmacie, Université de Picardie Jules Verne, 1 Rue des Louvels, 80037 Amiens, France;
| | - Mounia Khelifa
- inov3PT—Recherche Développement Innovation des Producteurs de Plants de Pomme de Terre, 43-45 Rue de Naples, 75008 Paris, France; (E.M.-L.); (M.K.)
| | - Sylvain Laclef
- Laboratoire de Glycochimie, des Antimicrobiens et des Agroressources (LG2A), Institut de Chimie de Picardie FR 3085, Université de Picardie Jules Verne, 33 Rue Saint Leu, 80039 Amiens, France
| | - Serge Pilard
- Plateforme-Analytique (PFA), Institut de Chimie de Picardie FR 3085, Université de Picardie Jules Verne, 33 Rue Saint Leu, 80039 Amiens, France;
| |
Collapse
|
3
|
Wang P, Xiao Y, Gao D, Long Y, Xie Z. The Gene paaZ of the Phenylacetic Acid (PAA) Catabolic Pathway Branching Point and ech outside the PAA Catabolon Gene Cluster Are Synergistically Involved in the Biosynthesis of the Iron Scavenger 7-Hydroxytropolone in Pseudomonas donghuensis HYS. Int J Mol Sci 2023; 24:12632. [PMID: 37628812 PMCID: PMC10454607 DOI: 10.3390/ijms241612632] [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: 06/21/2023] [Revised: 08/04/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
The newly discovered iron scavenger 7-hydroxytropolone (7-HT) is secreted by Pseudomonas donghuensis HYS. In addition to possessing an iron-chelating ability, 7-HT has various other biological activities. However, 7-HT's biosynthetic pathway remains unclear. This study was the first to report that the phenylacetic acid (PAA) catabolon genes in cluster 2 are involved in the biosynthesis of 7-HT and that two genes, paaZ (orf13) and ech, are synergistically involved in the biosynthesis of 7-HT in P. donghuensis HYS. Firstly, gene knockout and a sole carbon experiment indicated that the genes orf17-21 (paaEDCBA) and orf26 (paaG) were involved in the biosynthesis of 7-HT and participated in the PAA catabolon pathway in P. donghuensis HYS; these genes were arranged in gene cluster 2 in P. donghuensis HYS. Interestingly, ORF13 was a homologous protein of PaaZ, but orf13 (paaZ) was not essential for the biosynthesis of 7-HT in P. donghuensis HYS. A genome-wide BLASTP search, including gene knockout, complemented assays, and site mutation, showed that the gene ech homologous to the ECH domain of orf13 (paaZ) is essential for the biosynthesis of 7-HT. Three key conserved residues of ech (Asp39, His44, and Gly62) were identified in P. donghuensis HYS. Furthermore, orf13 (paaZ) could not complement the role of ech in the production of 7-HT, and the single carbon experiment indicated that paaZ mainly participates in PAA catabolism. Overall, this study reveals a natural association between PAA catabolon and the biosynthesis of 7-HT in P. donghuensis HYS. These two genes have a synergistic effect and different functions: paaZ is mainly involved in the degradation of PAA, while ech is mainly related to the biosynthesis of 7-HT in P. donghuensis HYS. These findings complement our understanding of the mechanism of the biosynthesis of 7-HT in the genus Pseudomonas.
Collapse
Affiliation(s)
| | | | | | - Yan Long
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China; (P.W.); (Y.X.); (D.G.)
| | - Zhixiong Xie
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China; (P.W.); (Y.X.); (D.G.)
| |
Collapse
|
4
|
Teng S, Wu T, Gao D, Wu S, Xiao Y, Long Y, Xie Z. Insight into the Global Negative Regulation of Iron Scavenger 7-HT Biosynthesis by the SigW/RsiW System in Pseudomonas donghuensis HYS. Int J Mol Sci 2023; 24:ijms24021184. [PMID: 36674714 PMCID: PMC9861184 DOI: 10.3390/ijms24021184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 01/04/2023] [Accepted: 01/05/2023] [Indexed: 01/11/2023] Open
Abstract
7-Hydroxytropolone (7-HT) is a unique iron scavenger synthesized by Pseudomonas donghuensis HYS that has various biological activities in addition to functioning as a siderophore. P. donghuensis HYS is more pathogenic than P. aeruginosa toward Caenorhabditis elegans, an observation that is closely linked to the biosynthesis of 7-HT. The nonfluorescent siderophore (nfs) gene cluster is responsible for the orderly biosynthesis of 7-HT and represents a competitive advantage that contributes to the increased survival of P. donghuensis HYS; however, the regulatory mechanisms of 7-HT biosynthesis remain unclear. This study is the first to propose that the ECF σ factor has a regulatory effect on 7-HT biosynthesis. In total, 20 ECF σ factors were identified through genome-wide scanning, and their responses to extracellular ferrous ions were characterized. We found that SigW was both significantly upregulated under high-iron conditions and repressed by an adjacent anti-σ factor. RNA-Seq results suggest that the SigW/RsiW system is involved in iron metabolism and 7-HT biosynthesis. Combined with the siderophore phenotype, we also found that SigW could inhibit siderophore synthesis, and this inhibition can be relieved by RsiW. EMSA assays proved that SigW, when highly expressed, can directly bind to the promoter region of five operons of the nfs cluster to inhibit the transcription of the corresponding genes and consequently suppress 7-HT biosynthesis. In addition, SigW not only directly negatively regulates structural genes related to 7-HT synthesis but also inhibits the transcription of regulatory proteins, including of the Gac/Rsm cascade system. Taken together, our results highlight that the biosynthesis of 7-HT is negatively regulated by SigW and that the SigW/RsiW system is involved in mechanisms for the regulation of iron homeostasis in P. donghuensis HYS. As a result of this work, we identified a novel mechanism for the global negative regulation of 7-HT biosynthesis, complementing our understanding of the function of ECF σ factors in Pseudomonas.
Collapse
|
5
|
Zboralski A, Biessy A, Ciotola M, Cadieux M, Albert D, Blom J, Filion M. Harnessing the genomic diversity of Pseudomonas strains against lettuce bacterial pathogens. Front Microbiol 2022; 13:1038888. [PMID: 36620043 PMCID: PMC9814014 DOI: 10.3389/fmicb.2022.1038888] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 12/05/2022] [Indexed: 12/24/2022] Open
Abstract
Lettuce is a major vegetable crop worldwide that is affected by numerous bacterial pathogens, including Xanthomonas hortorum pv. vitians, Pseudomonas cichorii, and Pectobacterium carotovorum. Control methods are scarce and not always effective. To develop new and sustainable approaches to contain these pathogens, we screened more than 1,200 plant-associated Pseudomonas strains retrieved from agricultural soils for their in vitro antagonistic capabilities against the three bacterial pathogens under study. Thirty-five Pseudomonas strains significantly inhibited some or all three pathogens. Their genomes were fully sequenced and annotated. These strains belong to the P. fluorescens and P. putida phylogenomic groups and are distributed in at least 27 species, including 15 validly described species. They harbor numerous genes and clusters of genes known to be involved in plant-bacteria interactions, microbial competition, and biocontrol. Strains in the P. putida group displayed on average better inhibition abilities than strains in the P. fluorescens group. They carry genes and biosynthetic clusters mostly absent in the latter strains that are involved in the production of secondary metabolites such as 7-hydroxytropolone, putisolvins, pyochelin, and xantholysin-like and pseudomonine-like compounds. The presence of genes involved in the biosynthesis of type VI secretion systems, tailocins, and hydrogen cyanide also positively correlated with the strains' overall inhibition abilities observed against the three pathogens. These results show promise for the development of biocontrol products against lettuce bacterial pathogens, provide insights on some of the potential biocontrol mechanisms involved, and contribute to public Pseudomonas genome databases, including quality genome sequences on some poorly represented species.
Collapse
Affiliation(s)
- Antoine Zboralski
- Centre de Recherche et de Développement de Saint-Jean-sur-Richelieu, Agriculture et Agroalimentaire Canada, Saint-Jean-sur-Richelieu, QC, Canada
| | - Adrien Biessy
- Centre de Recherche et de Développement de Saint-Jean-sur-Richelieu, Agriculture et Agroalimentaire Canada, Saint-Jean-sur-Richelieu, QC, Canada
| | - Marie Ciotola
- Centre de Recherche et de Développement de Saint-Jean-sur-Richelieu, Agriculture et Agroalimentaire Canada, Saint-Jean-sur-Richelieu, QC, Canada
| | - Mélanie Cadieux
- Centre de Recherche et de Développement de Saint-Jean-sur-Richelieu, Agriculture et Agroalimentaire Canada, Saint-Jean-sur-Richelieu, QC, Canada
| | - Daphné Albert
- Centre de Recherche et de Développement de Saint-Jean-sur-Richelieu, Agriculture et Agroalimentaire Canada, Saint-Jean-sur-Richelieu, QC, Canada
| | - Jochen Blom
- Bioinformatics and Systems Biology, Justus Liebig University Giessen, Giessen, Germany
| | - Martin Filion
- Centre de Recherche et de Développement de Saint-Jean-sur-Richelieu, Agriculture et Agroalimentaire Canada, Saint-Jean-sur-Richelieu, QC, Canada,*Correspondence: Martin Filion,
| |
Collapse
|
6
|
Masi M, Castaldi S, Sautua F, Pescitelli G, Carmona MA, Evidente A. Truncatenolide, a Bioactive Disubstituted Nonenolide Produced by Colletotrichum truncatum, the Causal Agent of Anthracnose of Soybean in Argentina: Fungal Antagonism and SAR Studies. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:9834-9844. [PMID: 35925677 PMCID: PMC9389607 DOI: 10.1021/acs.jafc.2c02502] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 07/13/2022] [Accepted: 07/22/2022] [Indexed: 06/15/2023]
Abstract
A bioactive disubstituted nonenolide, named truncatenolide, was produced by Colletotrichum truncatum, which was collected from infected tissues of soybean showing anthracnose symptoms in Argentina. This is a devastating disease that drastically reduces the yield of soybean production in the world. The fungus also produced a new trisubstituted oct-2-en-4-one, named truncatenone, and the well-known tyrosol and N-acetyltyramine. Truncatenolide and truncatenone were characterized by spectroscopic (essentially one-dimensional (1D) and two-dimensional (2D) 1H and 13C NMR and HR ESIMS) and chemical methods as (5E,7R,10R)-7-hydroxy-10-methyl-3,4,7,8,9,10-hexahydro-2H-oxecin-2-one and (Z)-6-hydroxy-3,5-dimethyloct-2-en-4-one, respectively. The geometry of the double bond of truncatenolide was assigned by the value of olefinic proton coupling constant and that of truncatenone by the correlation observed in the corresponding NOESY spectrum. The relative configuration of each stereogenic center was assigned with the help of 13C chemical shift and 1H-1H scalar coupling DFT calculations, while the absolute configuration assignment of truncatenolide was performed by electronic circular dichroism (ECD). When tested on soybean seeds, truncatenolide showed the strongest phytotoxic activity. Tyrosol and N-acetyltyramine also showed phytotoxicity to a lesser extent, while truncatenone weakly stimulated the growth of the seed root in comparison to the control. When assayed against Macrophomina phaseolina and Cercospora nicotianae, other severe pathogens of soybean, truncatenolide showed significant activity against M. phaseolina and total inhibition of C. nicotianae. Thus, some other fungal nonenolides and their derivatives were assayed for their antifungal activity against both fungi in comparison with truncatenolide. Pinolidoxin showed to a less extent antifungal activity against both fungi, while modiolide A selectively and totally inhibited only the growth of C. nicotianae. The SAR results and the potential of truncatenolide, modiolide A, and pinolidoxin as biofungicides were also discussed.
Collapse
Affiliation(s)
- Marco Masi
- Dipartimento
di Scienze Chimiche, Università di
Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Stefany Castaldi
- Dipartimento
di Biologia, Università di Napoli
Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Francisco Sautua
- Cátedra
de Fitopatología, Facultad de Agronomía, Universidad de Buenos Aires, C1417DSE Buenos Aires, Argentina
| | - Gennaro Pescitelli
- Dipartimento
di Chimica e Chimica Industriale, Università
di Pisa, Via Moruzzi
13, 56124 Pisa, Italy
| | - Marcelo Anibal Carmona
- Cátedra
de Fitopatología, Facultad de Agronomía, Universidad de Buenos Aires, C1417DSE Buenos Aires, Argentina
| | - Antonio Evidente
- Dipartimento
di Scienze Chimiche, Università di
Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| |
Collapse
|
7
|
Santos-Aberturas J, Vior NM. Beyond Soil-Dwelling Actinobacteria: Fantastic Antibiotics and Where to Find Them. Antibiotics (Basel) 2022; 11:195. [PMID: 35203798 PMCID: PMC8868522 DOI: 10.3390/antibiotics11020195] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/27/2022] [Accepted: 01/29/2022] [Indexed: 12/10/2022] Open
Abstract
Bacterial secondary metabolites represent an invaluable source of bioactive molecules for the pharmaceutical and agrochemical industries. Although screening campaigns for the discovery of new compounds have traditionally been strongly biased towards the study of soil-dwelling Actinobacteria, the current antibiotic resistance and discovery crisis has brought a considerable amount of attention to the study of previously neglected bacterial sources of secondary metabolites. The development and application of new screening, sequencing, genetic manipulation, cultivation and bioinformatic techniques have revealed several other groups of bacteria as producers of striking chemical novelty. Biosynthetic machineries evolved from independent taxonomic origins and under completely different ecological requirements and selective pressures are responsible for these structural innovations. In this review, we summarize the most important discoveries related to secondary metabolites from alternative bacterial sources, trying to provide the reader with a broad perspective on how technical novelties have facilitated the access to the bacterial metabolic dark matter.
Collapse
Affiliation(s)
| | - Natalia M. Vior
- Department of Molecular Microbiology, John Innes Centre, Norwich NR7 4UH, UK
| |
Collapse
|
8
|
Toplak M, Teufel R. Three Rings to Rule Them All: How Versatile Flavoenzymes Orchestrate the Structural Diversification of Natural Products. Biochemistry 2021; 61:47-56. [PMID: 34962769 PMCID: PMC8772269 DOI: 10.1021/acs.biochem.1c00763] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
![]()
The structural diversification
of natural products is instrumental
to their versatile bioactivities. In this context, redox tailoring
enzymes are commonly involved in the modification and functionalization
of advanced pathway intermediates en route to the mature natural products.
In recent years, flavoprotein monooxygenases have been shown to mediate
numerous redox tailoring reactions that include not only (aromatic)
hydroxylation, Baeyer–Villiger oxidation, or epoxidation reactions
but also oxygenations that are coupled to extensive remodeling of
the carbon backbone, which are often central to the installment of
the respective pharmacophores. In this Perspective, we will highlight
recent developments and discoveries in the field of flavoenzyme catalysis
in bacterial natural product biosynthesis and illustrate how the flavin
cofactor can be fine-tuned to enable chemo-, regio-, and stereospecific
oxygenations via distinct flavin-C4a-peroxide and flavin-N5-(per)oxide
species. Open questions remain, e.g., regarding the breadth of chemical
reactions enabled particularly by the newly discovered flavin-N5-oxygen
adducts and the role of the protein environment in steering such cascade-like
reactions. Outstanding cases involving different flavin oxygenating
species will be exemplified by the tailoring of bacterial aromatic
polyketides, including enterocin, rubromycins, rishirilides, mithramycin,
anthracyclins, chartreusin, jadomycin, and xantholipin. In addition,
the biosynthesis of tropone natural products, including tropolone
and tropodithietic acid, will be presented, which features a recently
described prototypical flavoprotein dioxygenase that may combine flavin-N5-peroxide
and flavin-N5-oxide chemistry. Finally, structural and mechanistic
features of selected enzymes will be discussed as well as hurdles
for their application in the formation of natural product derivatives
via bioengineering.
Collapse
Affiliation(s)
- Marina Toplak
- Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany
| | - Robin Teufel
- Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany
| |
Collapse
|
9
|
Krzyżanowska DM, Iwanicki A, Czajkowski R, Jafra S. High-Quality Complete Genome Resource of Tomato Rhizosphere Strain Pseudomonas donghuensis P482, a Representative of a Species with Biocontrol Activity Against Plant Pathogens. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2021; 34:1450-1454. [PMID: 34428926 DOI: 10.1094/mpmi-06-21-0136-a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Strain P482 was isolated from a tomato rhizosphere and classified as Pseudomonas donghuensis. The P. donghuensis species was first established in 2015 and currently consists of only four strains: P482, HYST, SVBP6, and 22G5. P. donghuensis strains antagonize plant pathogens, including bacteria, fungi, and oomycetes, and, therefore, are of high interest regarding their biological control potential to combat plant diseases. The antimicrobial activity of P. donghuensis P482 is based on the production of iron-scavenging compound 7-hydroxytropolone, antifungal volatile organic compounds, and as-yet-unidentified secondary metabolites. Here, we report a complete genome resource for P. donghuensis strain P482. The genome consists of a single chromosome (5,656,185 bp) with 5,258 open reading frames (5,158 protein-coding genes, 74 transfer RNAs, 22 ribosomal RNAs, 3 noncoding RNAs, and 1 transfer-messenger RNA) and no plasmid. We believe that information on the first high-quality, complete genome of P. donghuensis will provide resources for analyses targeting the biological control potential of this species and understanding the traits essential for plant-microbe interaction.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
Collapse
Affiliation(s)
- Dorota M Krzyżanowska
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of University of Gdańsk and Medical University of Gdańsk, University of Gdańsk, A. Abrahama 58, 80-307 Gdańsk, Poland
| | - Adam Iwanicki
- Division of Molecular Bacteriology, Intercollegiate Faculty of Biotechnology of University of Gdańsk and Medical University of Gdańsk, Medical University of Gdańsk, Gdańsk, Dębinki 1, 80-211, Poland
| | - Robert Czajkowski
- Laboratory of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology of University of Gdańsk and Medical University of Gdańsk, University of Gdańsk, A. Abrahama 58, 80-307 Gdańsk, Poland
| | - Sylwia Jafra
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of University of Gdańsk and Medical University of Gdańsk, University of Gdańsk, A. Abrahama 58, 80-307 Gdańsk, Poland
| |
Collapse
|
10
|
Duan Y, Toplak M, Hou A, Brock NL, Dickschat JS, Teufel R. A Flavoprotein Dioxygenase Steers Bacterial Tropone Biosynthesis via Coenzyme A-Ester Oxygenolysis and Ring Epoxidation. J Am Chem Soc 2021; 143:10413-10421. [PMID: 34196542 PMCID: PMC8283759 DOI: 10.1021/jacs.1c04996] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
![]()
Bacterial tropone
natural products such as tropolone, tropodithietic
acid, or the roseobacticides play crucial roles in various terrestrial
and marine symbiotic interactions as virulence factors, antibiotics,
algaecides, or quorum sensing signals. We now show that their poorly
understood biosynthesis depends on a shunt product from aerobic CoA-dependent
phenylacetic acid catabolism that is salvaged by the dedicated acyl-CoA
dehydrogenase-like flavoenzyme TdaE. Further characterization of TdaE
revealed an unanticipated complex catalysis, comprising substrate
dehydrogenation, noncanonical CoA-ester oxygenolysis, and final ring
epoxidation. The enzyme thereby functions as an archetypal flavoprotein
dioxygenase that incorporates both oxygen atoms from O2 into the substrate, most likely involving flavin-N5-peroxide and
flavin-N5-oxide species for consecutive CoA-ester cleavage and epoxidation,
respectively. The subsequent spontaneous decarboxylation of the reactive
enzyme product yields tropolone, which serves as a key virulence factor
in rice panicle blight caused by pathogenic edaphic Burkholderia
plantarii. Alternatively, the TdaE product is most likely
converted to more complex sulfur-containing secondary metabolites
such as tropodithietic acid from predominant marine Rhodobacteraceae (e.g., Phaeobacter inhibens).
Collapse
Affiliation(s)
- Ying Duan
- Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany
| | - Marina Toplak
- Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany
| | - Anwei Hou
- Kekulé-Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany
| | - Nelson L Brock
- Institute of Organic Chemistry, TU Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Jeroen S Dickschat
- Kekulé-Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany.,Institute of Organic Chemistry, TU Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Robin Teufel
- Faculty of Biology, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany
| |
Collapse
|
11
|
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.
Collapse
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.
| |
Collapse
|
12
|
Matuszewska M, Maciąg T, Rajewska M, Wierzbicka A, Jafra S. The carbon source-dependent pattern of antimicrobial activity and gene expression in Pseudomonas donghuensis P482. Sci Rep 2021; 11:10994. [PMID: 34040089 PMCID: PMC8154892 DOI: 10.1038/s41598-021-90488-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/12/2021] [Indexed: 02/04/2023] Open
Abstract
Pseudomonas donghuensis P482 is a tomato rhizosphere isolate with the ability to inhibit growth of bacterial and fungal plant pathogens. Herein, we analysed the impact of the carbon source on the antibacterial activity of P482 and expression of the selected genes of three genomic regions in the P482 genome. These regions are involved in the synthesis of pyoverdine, 7-hydroxytropolone (7-HT) and an unknown compound ("cluster 17") and are responsible for the antimicrobial activity of P482. We showed that the P482 mutants, defective in these regions, show variations and contrasting patterns of growth inhibition of the target pathogen under given nutritional conditions (with glucose or glycerol as a carbon source). We also selected and validated the reference genes for gene expression studies in P. donghuensis P482. Amongst ten candidate genes, we found gyrB, rpoD and mrdA the most stably expressed. Using selected reference genes in RT-qPCR, we assessed the expression of the genes of interest under minimal medium conditions with glucose or glycerol as carbon sources. Glycerol was shown to negatively affect the expression of genes necessary for 7-HT synthesis. The significance of this finding in the light of the role of nutrient (carbon) availability in biological plant protection is discussed.
Collapse
Affiliation(s)
- Marta Matuszewska
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of University of Gdansk and Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Tomasz Maciąg
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of University of Gdansk and Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Magdalena Rajewska
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of University of Gdansk and Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Aldona Wierzbicka
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of University of Gdansk and Medical University of Gdansk, University of Gdansk, Gdansk, Poland
| | - Sylwia Jafra
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of University of Gdansk and Medical University of Gdansk, University of Gdansk, Gdansk, Poland.
| |
Collapse
|
13
|
Masi M, Sautua F, Zatout R, Castaldi S, Arrico L, Isticato R, Pescitelli G, Carmona MA, Evidente A. Phaseocyclopentenones A and B, Phytotoxic Penta- and Tetrasubstituted Cyclopentenones Produced by Macrophomina phaseolina, the Causal Agent of Charcoal Rot of Soybean in Argentina. JOURNAL OF NATURAL PRODUCTS 2021; 84:459-465. [PMID: 33492968 DOI: 10.1021/acs.jnatprod.0c01287] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Two new penta- and tetrasubstituted cyclopentenones, named phaseocyclopentenones A and B (1 and 2), together with guignardone A (3), were isolated from Macrophomina phaseolina cultures. The phytopathogenic fungus was isolated from infected soybean tissues showing charcoal rot symptoms in Argentina. Charcoal rot is a devastating disease considering that soybean is one of the main legumes cultivated in the world. Phaseocyclopentenones A and B were characterized by 1D and 2D 1H and 13C NMR spectroscopic and HRESIMS spectrometric data and chemical methods as 4-benzoyl-3,4,5-trihydroxy-2-phenylcyclopent-2-enone and 3,5-dihydroxy-2,4-diphenylcyclopent-2-enone, respectively. The relative configuration of phaseocyclopentenones A and B was assigned by 1H and NOESY NMR methods, while their absolute configurations were assigned by electronic circular dichroism methods. When assayed on a nonhost plant (Solanum lycopersicum L.) by the leaf puncture assay, phaseocyclopentenones A and B and guignardone A showed phytotoxic activity, while only 1 and 2 were toxic when tested on cuttings of the same plant. No phytotoxicity or antifungal activity was detected for the three compounds on the host plant soybean (Glycine max L.) and against some of its fungal pathogens, namely, Cercospora nicotianae and Colletotrichum truncatum, also isolated from infected soybean plants in Argentina.
Collapse
Affiliation(s)
- Marco Masi
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Francisco Sautua
- Facultad de Agronomía, Cátedra de Fitopatología, Universidad de Buenos Aires, C1053 CABA Buenos Aires, Argentina
| | - Roukia Zatout
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
- Laboratoire de Mycologie, de Biotechnologie et de l'Activité Microbienne (LaMyBAM), Département de Biologie Appliquée, Université des Frères Mentouri, Constantine1, BP, 325 Route de Aïn El Bey, Constantine 25017, Algeria
| | - Stefany Castaldi
- Dipartimento di Biologia, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Lorenzo Arrico
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Moruzzi 13, 56124 Pisa, Italy
| | - Rachele Isticato
- Dipartimento di Biologia, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Gennaro Pescitelli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Moruzzi 13, 56124 Pisa, Italy
| | - Marcelo Anibal Carmona
- Facultad de Agronomía, Cátedra de Fitopatología, Universidad de Buenos Aires, C1053 CABA Buenos Aires, Argentina
| | - Antonio Evidente
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| |
Collapse
|
14
|
Moffat AD, Elliston A, Patron NJ, Truman AW, Carrasco Lopez JA. A biofoundry workflow for the identification of genetic determinants of microbial growth inhibition. Synth Biol (Oxf) 2021; 6:ysab004. [PMID: 33623825 PMCID: PMC7889406 DOI: 10.1093/synbio/ysab004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 01/04/2021] [Accepted: 01/12/2021] [Indexed: 11/20/2022] Open
Abstract
Biofoundries integrate high-throughput software and hardware platforms with synthetic biology approaches to enable the design, execution and analyses of large-scale experiments. The unique and powerful combination of laboratory infrastructure and expertise in molecular biology and automation programming, provide flexible resources for a wide range of workflows and research areas. Here, we demonstrate the applicability of biofoundries to molecular microbiology, describing the development and application of automated workflows to identify the genetic basis of growth inhibition of the plant pathogen Streptomyces scabies by a Pseudomonas strain isolated from a potato field. Combining transposon mutagenesis with automated high-throughput antagonistic assays, the workflow accelerated the screening of 2880 mutants to correlate growth inhibition with a biosynthetic gene cluster within 2 weeks.
Collapse
Affiliation(s)
- Alaster D Moffat
- Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich, UK
| | - Adam Elliston
- Department of Engineering Biology, Earlham Institute, Norwich Research Park, Norwich, UK
| | - Nicola J Patron
- Department of Engineering Biology, Earlham Institute, Norwich Research Park, Norwich, UK
| | - Andrew W Truman
- Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich, UK
| | - Jose A Carrasco Lopez
- Department of Engineering Biology, Earlham Institute, Norwich Research Park, Norwich, UK
| |
Collapse
|
15
|
Amacker N, Gao Z, Agaras BC, Latz E, Kowalchuk GA, Valverde CF, Jousset A, Weidner S. Biocontrol Traits Correlate With Resistance to Predation by Protists in Soil Pseudomonads. Front Microbiol 2020; 11:614194. [PMID: 33384680 PMCID: PMC7769776 DOI: 10.3389/fmicb.2020.614194] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 11/19/2020] [Indexed: 12/11/2022] Open
Abstract
Root-colonizing bacteria can support plant growth and help fend off pathogens. It is clear that such bacteria benefit from plant-derived carbon, but it remains ambiguous why they invest in plant-beneficial traits. We suggest that selection via protist predation contributes to recruitment of plant-beneficial traits in rhizosphere bacteria. To this end, we examined the extent to which bacterial traits associated with pathogen inhibition coincide with resistance to protist predation. We investigated the resistance to predation of a collection of Pseudomonas spp. against a range of representative soil protists covering three eukaryotic supergroups. We then examined whether patterns of resistance to predation could be explained by functional traits related to plant growth promotion, disease suppression and root colonization success. We observed a strong correlation between resistance to predation and phytopathogen inhibition. In addition, our analysis highlighted an important contribution of lytic enzymes and motility traits to resist predation by protists. We conclude that the widespread occurrence of plant-protective traits in the rhizosphere microbiome may be driven by the evolutionary pressure for resistance against predation by protists. Protists may therefore act as microbiome regulators promoting native bacteria involved in plant protection against diseases.
Collapse
Affiliation(s)
- Nathalie Amacker
- Ecology and Biodiversity Group, Institute of Environmental Biology, University of Utrecht, Utrecht, Netherlands
| | - Zhilei Gao
- Ecology and Biodiversity Group, Institute of Environmental Biology, University of Utrecht, Utrecht, Netherlands
| | - Betina C. Agaras
- Laboratorio de Fisiología y Genética de Bacterias Beneficiosas para Plantas, Departamento de Ciencia y Tecnología, Centro de Bioquímica y Microbiología del Suelo, Universidad Nacional de Quilmes, Buenos Aires, Argentina
| | - Ellen Latz
- German Centre for Integrative Biodiversity Research (iDiv), Halle-Jena-Leipzig, Leipzig, Germany
| | - George A. Kowalchuk
- Ecology and Biodiversity Group, Institute of Environmental Biology, University of Utrecht, Utrecht, Netherlands
| | - Claudio F. Valverde
- Laboratorio de Fisiología y Genética de Bacterias Beneficiosas para Plantas, Departamento de Ciencia y Tecnología, Centro de Bioquímica y Microbiología del Suelo, Universidad Nacional de Quilmes, Buenos Aires, Argentina
| | - Alexandre Jousset
- Ecology and Biodiversity Group, Institute of Environmental Biology, University of Utrecht, Utrecht, Netherlands
| | - Simone Weidner
- Ecology and Biodiversity Group, Institute of Environmental Biology, University of Utrecht, Utrecht, Netherlands
- Department of Microbial Ecology, Netherlands Institute of Ecology, Wageningen, Netherlands
| |
Collapse
|
16
|
Zboralski A, Filion M. Genetic factors involved in rhizosphere colonization by phytobeneficial Pseudomonas spp. Comput Struct Biotechnol J 2020; 18:3539-3554. [PMID: 33304453 PMCID: PMC7711191 DOI: 10.1016/j.csbj.2020.11.025] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 11/10/2020] [Accepted: 11/12/2020] [Indexed: 12/13/2022] Open
Abstract
Plant growth-promoting rhizobacteria (PGPR) actively colonize the soil portion under the influence of plant roots, called the rhizosphere. Many plant-beneficial Pseudomonas spp. have been characterized as PGPR. They are ubiquitous rod-shaped motile Gram-negative bacteria displaying a high metabolic versatility. Their capacity to protect plants from pathogens and improve plant growth closely depends on their rhizosphere colonization abilities. Various molecular and cellular mechanisms are involved in this complex process, such as chemotaxis, biofilm formation, secondary metabolites biosynthesis, metabolic versatility, and evasion of plant immunity. The burst in Pseudomonas spp. genome sequencing in recent years has been crucial to better understand how they colonize the rhizosphere. In this review, we discuss the recent advances regarding these mechanisms and the underlying bacterial genetic factors required for successful rhizosphere colonization.
Collapse
Affiliation(s)
- Antoine Zboralski
- Department of Biology, Université de Moncton, Moncton, NB E1A 3E9, Canada
| | - Martin Filion
- Research and Development Centre, Agriculture and Agri-Food Canada, Saint-Jean-sur-Richelieu, QC J3B 3E6, Canada
| |
Collapse
|
17
|
Tao X, Zhang H, Gao M, Li M, Zhao T, Guan X. Pseudomonas species isolated via high-throughput screening significantly protect cotton plants against verticillium wilt. AMB Express 2020; 10:193. [PMID: 33118043 PMCID: PMC7593376 DOI: 10.1186/s13568-020-01132-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 10/18/2020] [Indexed: 12/15/2022] Open
Abstract
Verticillium wilt (VW) caused by Verticillium dahliae is a devastating soil-borne disease that causes severe yield losses in cotton and other major crops worldwide. Here we conducted a high-throughput screening of isolates recovered from 886 plant rhizosphere samples taken from the three main cotton-producing areas of China. Fifteen isolates distributed in different genera of bacteria that showed inhibitory activity against V. dahliae were screened out. Of these, two Pseudomonas strains, P. protegens XY2F4 and P. donghuensis 22G5, showed significant inhibitory action against V. dahliae. Additional comparative genomic analyses and phenotypical assays confirmed that P. protegens XY2F4 and P. donghuensis 22G5 were the strains most efficient at protecting cotton plants against VW due to specific biological control products they produced. Importantly, we identified a significant efficacy of the natural tropolone compound 7-hydroxytropolone (7-HT) against VW. By phenotypical assay using the wild-type 22G5 and its mutant strain in 7-HT production, we revealed that the 7-HT produced by P. donghuensis is the major substance protecting cotton against VW. This study reveals that Pseudomonas specifically has gene clusters that allow the production of effective antipathogenic metabolites that can now be used as new agents in the biocontrol of VW.
Collapse
Affiliation(s)
- Xiaoyuan Tao
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Hailin Zhang
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Mengtao Gao
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Menglin Li
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Ting Zhao
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Xueying Guan
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China.
| |
Collapse
|
18
|
Pseudomonas donghuensis HYS 7-hydroxytropolone contributes to pathogenicity toward Caenorhabditis elegans and is influenced by pantothenic acid. Biochem Biophys Res Commun 2020; 533:50-56. [PMID: 32921415 DOI: 10.1016/j.bbrc.2020.08.067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 08/20/2020] [Indexed: 12/25/2022]
Abstract
Pseudomonas donghuensis HYS, a bacterial strain identified from Donghu Lake, has tremendous toxicity toward Caenorhabditis elegans and is characterized by high 7-hydroxytropolone siderophore production. Here, the relationship between pathogenic siderophore production and pantothenic acid was evaluated. The pathogenicity of P. donghuensis HYS was illustrated using C. elegans as a host. Based on slow-killing assay findings, a 7-hydroxytropolone deficiency-causing mutation attenuated P. donghuensis HYS pathogenicity, which was restored by the addition of extracted 7-hydroxytropolone. Moreover, data from real-time qPCR analysis and characteristic absorption assays indicated that pantothenic acid deficiency repressed transcriptional levels of orf9, which further reduced 7-hydroxytropolone production. Furthermore, slow-killing assays indicated that panB and pantothenic acid affected the virulence of P. donghuensis. These results indicate that a 7-hydroxytropolone siderophore-producing strain is virulent toward C. elegans. Our findings demonstrate that pantothenic acid is associated with P. donghuensis siderophore production-related pathogenicity.
Collapse
|
19
|
Sobrero PM, Valverde C. Comparative Genomics and Evolutionary Analysis of RNA-Binding Proteins of the CsrA Family in the Genus Pseudomonas. Front Mol Biosci 2020; 7:127. [PMID: 32754614 PMCID: PMC7366521 DOI: 10.3389/fmolb.2020.00127] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 06/02/2020] [Indexed: 12/15/2022] Open
Abstract
Gene expression is adjusted according to cellular needs through a combination of mechanisms acting at different layers of the flow of genetic information. At the posttranscriptional level, RNA-binding proteins are key factors controlling the fate of nascent and mature mRNAs. Among them, the members of the CsrA family are small dimeric proteins with heterogeneous distribution across the bacterial tree of life, that act as global regulators of gene expression because they recognize characteristic sequence/structural motifs (short hairpins with GGA triplets in the loop) present in hundreds of mRNAs. The regulatory output of CsrA binding to mRNAs is counteracted in most cases by molecular mimic, non-protein coding RNAs that titrate the CsrA dimers away from the target mRNAs. In γ-proteobacteria, the regulatory modules composed by CsrA homologs and the corresponding antagonistic sRNAs, are mastered by two-component systems of the GacS-GacA type, which control the transcription and the abundance of the sRNAs, thus constituting the rather linear cascade Gac-Rsm that responds to environmental or cellular signals to adjust and coordinate the expression of a set of target genes posttranscriptionally. Within the γ-proteobacteria, the genus Pseudomonas has been shown to contain species with different number of active CsrA (RsmA) homologs and of molecular mimic sRNAs. Here, with the help of the increasing availability of genomic data we provide a comprehensive state-of-the-art picture of the remarkable multiplicity of CsrA lineages, including novel yet uncharacterized paralogues, and discuss evolutionary aspects of the CsrA subfamilies of the genus Pseudomonas, and implications of the striking presence of csrA alleles in natural mobile genetic elements (phages and plasmids).
Collapse
Affiliation(s)
- Patricio Martín Sobrero
- 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
| | - 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
| |
Collapse
|