Induced Expression of Sarcotoxin IA Enhanced Host Resistance Against Both Bacterial and Fungal Pathogens in Transgenic Tobacco

We demonstrate here that induced expression of sarcotoxin IA, a bactericidal peptide from Sarcophaga peregrina, enhanced the resistance of transgenic tobacco plants to both bacterial and fungal pathogens. The peptide was produced with a modified PR1a promoter, which is further activated by salicylic acid treatment and necrotic lesion formation by pathogen infection. Host resistance to infection of bacteria Erwinia carotovora subsp. carotovora and Pseudomonas syringae pv. tabaci was shown to be dependent on the amounts of sarcotoxin IA expressed. Since we found antifungal activity of the peptide in vitro, transgenic seedlings were also inoculated with fungal pathogens Rhizoctonia solani and Pythium aphanidermatum. Transgenic plants expressing higher levels of sarcotoxin were able to withstand fungal infection and remained healthy even after 4 weeks, while control plants were dead by fungal infection after 2 weeks.

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Transgenic expression of gallerimycin, a novel antifungal insect defensin from the greater wax moth Galleria mellonella, confers resistance to pathogenic fungi in tobacco

Biological Chemistry ◽

10.1515/bc.2006.071 ◽

2006 ◽

Vol 387 (5) ◽

pp. 549-557 ◽

Cited By ~ 50

Author(s):

Gregor Langen ◽

Jafargholi Imani ◽

Boran Altincicek ◽

Gernot Kieseritzky ◽

Karl-Heinz Kogel ◽

...

Keyword(s):

Transgenic Tobacco ◽

Fungal Pathogens ◽

Galleria Mellonella ◽

Ectopic Expression ◽

Pathogenic Fungi ◽

Transgenic Expression ◽

Greater Wax Moth ◽

Insect Defensin ◽

Wax Moth

Abstract A cDNA encoding gallerimycin, a novel antifungal peptide from the greater wax moth Galleria mellonella, was isolated from a cDNA library of genes expressed during innate immune response in the caterpillars. Upon ectopic expression of gallerimycin in tobacco, using Agrobacterium tumefaciens as a vector, gallerimycin conferred resistance to the fungal pathogens Erysiphe cichoracearum and Sclerotinia minor. Quantification of gallerimycin mRNA in transgenic tobacco by real-time PCR confirmed transgenic expression under control of the inducible mannopine synthase promoter. Leaf sap and intercellular washing fluid from transgenic tobacco inhibited in vitro germination and growth of the fungal pathogens, demonstrating that gallerimycin is secreted into intercellular spaces. The feasibility of the use of gallerimycin to counteract fungal diseases in crop plants is discussed.

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Antimicrobial activity screening of rhizosphere soil bacteria from tomato and genome-based analysis of their antimicrobial biosynthetic potential

BMC Genomics ◽

10.1186/s12864-020-07346-8 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Lu Zhou ◽

Chunxu Song ◽

Zhibo Li ◽

Oscar P. Kuipers

Keyword(s):

Antimicrobial Activity ◽

Plant Growth ◽

Disease Control ◽

Pseudomonas Syringae ◽

Rhizosphere Soil ◽

Erwinia Carotovora ◽

Gene Clusters ◽

Vast Number ◽

Tomato Disease

Abstract Background Tomato plant growth is frequently hampered by a high susceptibility to pests and diseases. Traditional chemical control causes a serious impact on both the environment and human health. Therefore, seeking environment-friendly and cost-effective green methods in agricultural production becomes crucial nowadays. Plant Growth Promoting Rhizobacteria (PGPR) can promote plant growth through biological activity. Their use is considered to be a promising sustainable approach for crop growth. Moreover, a vast number of biosynthetic gene clusters (BGCs) for secondary metabolite production are being revealed in PGPR, which helps to find potential anti-microbial activities for tomato disease control. Results We isolated 181 Bacillus-like strains from healthy tomato, rhizosphere soil, and tomato tissues. In vitro antagonistic assays revealed that 34 Bacillus strains have antimicrobial activity against Erwinia carotovora, Pseudomonas syringae; Rhizoctonia solani; Botrytis cinerea; Verticillium dahliae and Phytophthora infestans. The genomes of 10 Bacillus and Paenibacillus strains with good antagonistic activity were sequenced. Via genome mining approaches, we identified 120 BGCs encoding NRPs, PKs-NRPs, PKs, terpenes and bacteriocins, including known compounds such as fengycin, surfactin, bacillibactin, subtilin, etc. In addition, several novel BGCs were identified. We discovered that the NRPs and PKs-NRPs BGCs in Bacillus species are encoding highly conserved known compounds as well as various novel variants. Conclusions This study highlights the great number of varieties of BGCs in Bacillus strains. These findings pave the road for future usage of Bacillus strains as biocontrol agents for tomato disease control and are a resource arsenal for novel antimicrobial discovery.

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Identification and in Vitro Susceptibility Pattern of Fungal Pathogens in Immunocompromised Patients with invasive Fungal Infections

10.51429/ejmm30317 ◽

2021 ◽

Vol 30 (3) ◽

pp. 127-134

Author(s):

Shaimaa A.S. Selem ◽

Neveen A. Hassan ◽

Mohamed Z. Abd El-Rahman ◽

Doaa M. Abd El-Kareem

Keyword(s):

Intensive Care ◽

Fungal Infection ◽

Fungal Pathogens ◽

Fungal Infections ◽

Antifungal Susceptibility ◽

Invasive Fungal Infections ◽

Immunocompromised Patients ◽

University Hospitals ◽

Vitek 2

Background: In intensive care units, invasive fungal infections have become more common, particularly among immunocompromised patients. Early identification and starting the treatment of those patients with antifungal therapy is critical for preventing unnecessary use of toxic antifungal agents. Objective: The aim of this research is to determine which common fungi cause invasive fungal infection in immunocompromised patients, as well as their antifungal susceptibility patterns in vitro, in Assiut University Hospitals. Methodology: This was a hospital based descriptive study conducted on 120 patients with clinical suspicion of having fungal infections admitted at different Intensive Care Units (ICUs) at Assiut University Hospitals. Direct microscopic examination and inoculation on Sabouraud Dextrose Agar (SDA) were performed on the collected specimens. Isolated yeasts were classified using phenotypic methods such as chromogenic media (Brilliance Candida agar), germ tube examination, and the Vitek 2 system for certain isolates, while the identification of mould isolates was primarily based on macroscopic and microscopic characteristics. Moulds were tested in vitro for antifungal susceptibility using the disc diffusion, and yeast were tested using Vitek 2 device cards. Results: In this study, 100 out of 120 (83.3%) of the samples were positive for fungal infection. Candida and Aspergillus species were the most commonly isolated fungal pathogens. The isolates had the highest sensitivity to Amphotericin B (95 %), followed by Micafungin (94 %) in an in vitro sensitivity survey. Conclusion: Invasive fungal infections are a leading cause of morbidity and mortality in immunocompromised patients, with Candida albicans being the most frequently isolated yeast from various clinical specimens; however, the rise in resistance, especially to azoles, is a major concern.

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Effects of Pesticides on the Reduction of Plant and Human Pathogenic Bacteria in Application Water

Journal of Food Protection ◽

10.4315/0362-028x.jfp-12-440 ◽

2013 ◽

Vol 76 (4) ◽

pp. 719-722 ◽

Cited By ~ 3

Author(s):

MICHAEL MAHOVIC ◽

GANYU GU ◽

STEVEN RIDEOUT

Keyword(s):

Pseudomonas Syringae ◽

Xanthomonas Campestris ◽

Pathogenic Bacteria ◽

Plant Pathogens ◽

Erwinia Carotovora ◽

Noticeable Effect ◽

Tomato Production ◽

Initial Application ◽

Treated Plant

Overhead spray applications of in-field tomato treatments dissolved in aqueous solutions have specific pest targets (fungal, bacterial, insect, or other). Any organism present in the solution or on treated plant surfaces that is not a specific target of the application is unlikely inactivated and can instead be spread through the phyllosphere. In this laboratory study, commercially labeled pesticides (including Actigard 50WG, Bravo Weather Stik 6F, Cabrio 20EG, Kasumin, Kocide 3000 46WG, Oxidate 27L, Penncozeb 75DF, ProPhyt 54.5L, Stimplex 100L, Firewall, 22.4WP, and Tanos 50DF) in common use in commercial tomato production fields of the Eastern Shore of Virginia were investigated for activity against in vitro bacterial contamination of pesticide application waters. Pesticides of interest were tank mixed individually with one of the plant pathogens Ralstonia solanacearum, Xanthomonas campestris pv. vesicatoria, Pseudomonas syringae pv. tomato, Erwinia carotovora subsp. carotovora, or one of two serovars (Newport and Montevideo) of the human pathogen Salmonella enterica to assess reduction values during the average time between mixing and initial application. Observations suggested that while some treatments had a noticeable effect on population levels, only the oxidizer, peroxyacetic acid, showed significant and consistent levels of suppression against all bacteria investigated, at levels that could have practical implications.

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Chemotaxis of some phytopathogenic bacteria to fungal propagules in vitro and in soil

Canadian Journal of Microbiology ◽

10.1139/m88-037 ◽

1988 ◽

Vol 34 (2) ◽

pp. 196-199 ◽

Cited By ~ 7

Author(s):

W. C. Lim ◽

J. L. Lockwood

Keyword(s):

Pseudomonas Syringae ◽

Xanthomonas Campestris ◽

Pathogenic Bacteria ◽

Erwinia Carotovora ◽

Bipolaris Sorokiniana ◽

Macrophomina Phaseolina ◽

Plant Pathogenic Bacteria ◽

Fungal Propagules ◽

Xanthomonas Campestris Pv Campestris

The motile plant pathogenic bacteria Erwinia carotovora pv. carotovora, Pseudomonas syringae pv. phaseolicola, and Xanthomonas campestris pv. campestris were strongly attracted to conidia of Bipolaris sorokiniana, B. victoriae, and to sclerotia of Macrophomina phaseolina and their exudates in vitro and in soil, but not to phosphate buffer or buffer–soil mixtures. Bacteria accumulated radioactivity within 1 h after being placed in exudates from 14C-labelled conidia of B. sorokiniana. After 5 h, radioactivity of the 14C-labelled exudate was reduced to 29–54% of that in the original medium. Exudates from fungal propagules may act as attractants and substrates for motile plant pathogenic bacteria in soil.

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Bioassay-Guided Isolation of Broad-Spectrum Fungicidal Active Compound from Artemisia ordosica

Metabolites ◽

10.3390/metabo11090629 ◽

2021 ◽

Vol 11 (9) ◽

pp. 629

Author(s):

Gaijuan Tang ◽

Shuyu Yang ◽

Wenqiong Hu ◽

Jingyi Jiang ◽

He Yan ◽

...

Keyword(s):

Pseudomonas Syringae ◽

Broad Spectrum ◽

Xanthomonas Campestris ◽

Tomato Fruit ◽

Pathogenic Fungi ◽

Erwinia Carotovora ◽

Artemisia Ordosica ◽

Active Compounds

To avoid the widespread resistance of commercial fungicides, new broad-spectrum botanical fungicides need to be developed. In previous bioactive screening assays, extracts of Artemisia ordosica Krasch. (A. ordosica) had highly antifungal activities, but the responsible phytochemicals were unidentified. In this study, active compounds of A. ordosica extracts were identified using a bioassay-guided method, and antifungal assays were performed in vitro and in vivo. The bioactive compounds were dissolved in petroleum ether, and the best antifungal fraction contained four compounds: trans-dehydromatricaria ester (TDDE), 7, 4-demetylnringenin, capillarin, and stearic acid. Among them, TDDE exhibited the highest antifungal activity against six pathogenic fungi and five bacteria. It exhibited significant fungicidal activity against Thanatephorus cucumeris and Botrytis cinerea with EC50 values of 0.464 μg/mL and 1.4 μg/mL, respectively. The living tissue bioassay results showed that the relative protection effects (RPE) of TDDE on tomato leaves, tomato fruit, and strawberry leaves infected with B. cinerea reached 76.78%, 86.2%, and 80.89%, respectively. In pot experiments, the RPE on tomato and strawberry plants infected with B. cinerea reached 84.11% and 96.37%, respectively. Morphological and physiological examination showed that TDDE had significant inhibitory effects on mycelial growth, including increased top offshoot, contorted hyphal tips, and extravasated cytochylema. Meanwhile, bactericidal activities of TDDE were significantly higher than kanamycin and streptomycin in five bacteria, and the plant tissue experiments further demonstrated that it had an 88.31% RPE on walnut leaves infected with Xanthomonas campestris pv. jugiandis, 72.18% RPE on potato infected with Erwinia carotovora subsp. carotovora, and 82.50% RPE on kiwifruit branches infected with Pseudomonas syringae pv. actinidiae. The active compounds isolated from A. ordosica in this study show great potential value for developing broad-spectrum fungicides, and also provide an important way to identify and isolate new bioactive products from medicinal plants.

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Antimicrobial activity screening of rhizosphere soil bacteria from tomato and genome-based analysis of their antimicrobial biosynthetic potential

10.21203/rs.3.rs-26812/v2 ◽

2020 ◽

Author(s):

Lu Zhou ◽

Chunxu Song ◽

Zhibo Li ◽

Oscar P. Kuipers

Keyword(s):

Antimicrobial Activity ◽

Plant Growth ◽

Disease Control ◽

Pseudomonas Syringae ◽

Rhizosphere Soil ◽

Erwinia Carotovora ◽

Gene Clusters ◽

Vast Number ◽

Tomato Disease

Abstract Background: Tomato plant growth is frequently hampered by a high susceptibility to pests and diseases. Traditional chemical control causes a serious impact on both the environment and human health. Therefore, seeking environment-friendly and cost-effective green methods in agricultural production becomes crucial nowadays. Plant Growth Promoting Rhizobacteria (PGPR) can promote plant growth through biological activity. Their use is considered to be a promising sustainable approach for crop growth. Moreover, a vast number of biosynthetic gene clusters (BGCs) for secondary metabolite production are being revealed in PGPR, which helps to find potential anti-microbial activities for tomato disease control. Results: We isolated 181 Bacillus-like strains from healthy tomato, rhizosphere soil, and tomato tissues. In vitro antagonistic assays revealed that 34 Bacillus strains have antimicrobial activity against Erwinia carotovora, Pseudomonas syringae; Rhizoctonia solani; Botrytis cinerea; Verticillium dahliae and Phytophthora infestans. The genomes of 10 Bacillus and Paenibacillus strains with good antagonistic activity were sequenced. Via genome mining approaches, we identified 120 BGCs encoding NRPs, PKs-NRPs, PKs, terpenes and bacteriocins, including known compounds such as fengycin, surfactin, bacillibactin, subtilin, etc. In addition, several novel BGCs were identified. We discovered that the NRPs and PKs-NRPs BGCs in Bacillus species are encoding highly conserved known compounds as well as various novel variants. Conclusions: This study highlights the great number of varieties of BGCs in Bacillus strains. These findings pave the road for future usage of Bacillus strains as biocontrol agents for tomato disease control and are a resource arsenal for novel antimicrobial discovery.

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Arabidopsis MAPKKK δ-1 is required for full immunity against bacterial and fungal infection

Journal of Experimental Botany ◽

10.1093/jxb/erz556 ◽

2019 ◽

Vol 71 (6) ◽

pp. 2085-2097 ◽

Cited By ~ 1

Author(s):

Tomoya Asano ◽

Thi Hang-Ni Nguyen ◽

Michiko Yasuda ◽

Yasir Sidiq ◽

Kohji Nishimura ◽

...

Keyword(s):

Disease Resistance ◽

Fungal Infection ◽

Pseudomonas Syringae ◽

Fusarium Species ◽

Bacterial Pathogen ◽

Mitogen Activated Protein Kinase ◽

Trichothecene Mycotoxin ◽

Mitogen Activated Protein

Abstract The genome of Arabidopsis encodes more than 60 mitogen-activated protein kinase kinase (MAPKK) kinases (MAPKKKs); however, the functions of most MAPKKKs and their downstream MAPKKs are largely unknown. Here, MAPKKK δ-1 (MKD1), a novel Raf-like MAPKKK, was isolated from Arabidopsis as a subunit of a complex including the transcription factor AtNFXL1, which is involved in the trichothecene phytotoxin response and in disease resistance against the bacterial pathogen Pseudomonas syringae pv. tomato DC3000 (PstDC3000). A MKD1-dependent cascade positively regulates disease resistance against PstDC3000 and the trichothecene mycotoxin-producing fungal pathogen Fusarium sporotrichioides. MKD1 expression was induced by trichothecenes derived from Fusarium species. MKD1 directly interacted with MKK1 and MKK5 in vivo, and phosphorylated MKK1 and MKK5 in vitro. Correspondingly, mkk1 mutants and MKK5RNAi transgenic plants showed enhanced susceptibility to F. sporotrichioides. MKD1 was required for full activation of two MAPKs (MPK3 and MPK6) by the T-2 toxin and flg22. Finally, quantitative phosphoproteomics suggested that an MKD1-dependent cascade controlled phosphorylation of a disease resistance protein, SUMO, and a mycotoxin-detoxifying enzyme. Our findings suggest that the MKD1–MKK1/MKK5–MPK3/MPK6-dependent signaling cascade is involved in the full immune responses against both bacterial and fungal infection.

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THE ACTIVITY OF ESSENTIAL OILS OBTAINED FROM SPECIES AND INTERSPECIES HYBRIDS OF THE Mentha GENUS AGAINST SELECTED PLANT PATHOGENIC BACTERIA

Acta Scientiarum Polonorum Hortorum Cultus ◽

10.24326/asphc.2018.6.17 ◽

2018 ◽

Vol 17 (6) ◽

pp. 167-174 ◽

Cited By ~ 1

Author(s):

Małgorzata Schollenberger ◽

Tomasz M. Staniek ◽

Elżbieta Paduch-Cichal ◽

Beata Dasiewicz ◽

Agnieszka Gadomska-Gajadhur ◽

...

Keyword(s):

Essential Oils ◽

Pseudomonas Syringae ◽

Pathogenic Bacteria ◽

Antimicrobial Effect ◽

Mentha Piperita ◽

Mentha Spicata ◽

Plant Essential Oils ◽

Plant Pathogenic Bacteria ◽

Interspecies Hybrids

Plant essential oils of six aromatic herb species and interspecies hybrids of the family Lamiaceae – chocolate mint (Mentha piperita × ‘Chocolate’), pineapple mint (Mentha suaveolens ‘Variegata’), apple mint (Mentha × rotundifolia), spearmint (Mentha spicata), orange mint (Mentha × piperita ‘Granada’) and strawberry mint (Mentha × villosa ‘Strawberry’) – were investigated for antimicrobial effects against plant pathogenic bacteria: Agrobacterium tumefaciens, Pseudomonas syringae pv. syringae and Xanthomonas arboricola pv. corylina. The screening was carried out in vitro on agar plates filled with the target organism. All essential oils screened exhibited a higher level of antibacterial activity against A. tumefaciens and X. arboricola pv. corylina than streptomycin used as a standard in all tests. The antimicrobial effect of streptomycin and five mint oils was at the same level for P. syringae pv. syringae. There were no significant differences in the influence of the chocolate mint oil on the growth inhibition of all bacteria tested. Plant essential oils from pineapple mint, apple mint, spearmint and strawberry mint showed the weakest antimicrobial activity against P. syringae pv. syringae and the strongest towards A. tumefaciens and X. arboricola pv. corylina. The essential oils from strawberry mint, pineapple mint, spearmint and apple mint had the strongest effect on A. tumefaciens, and the lowest inhibitory activity was exhibited by the chocolate mint and orange mint essential oils. X. arboricola pv. corylina was the most sensitive to the strawberry mint, pineapple mint and spearmint oils. The chocolate mint oil showed the greatest activity against P. syringae pv. syringae.

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Comparative Mapping of Three Bacterial, Three Fungal, and One Virus Disease-resistance Genes in Common Bean

HortScience ◽

10.21273/hortsci.33.3.547a ◽

1998 ◽

Vol 33 (3) ◽

pp. 547a-547

Author(s):

Geunhwa Jung ◽

James Nienhuis ◽

Dermot P. Coyne ◽

H.M. Ariyarathne

Keyword(s):

Disease Resistance ◽

Common Bean ◽

Pseudomonas Syringae ◽

Resistance Genes ◽

Fungal Pathogens ◽

Xanthomonas Campestris ◽

Virus Disease ◽

Disease Resistance Genes ◽

Brown Spot ◽

Viral Pathogen

Common bacterial blight (CBB), bacterial brown spot (BBS), and halo blight (HB), incited by the bacterial pathogens Xanthomonas campestris pv. phaseoli (Smith) Dye, Pseodomonas syringae pv. syringa, and Pseudomonas syringae pv. phaseolicola, respectively are important diseases of common bean. In addition three fungal pathogens, web blight (WB) Thanatephorus cucumeris, rust Uromyces appendiculatus, and white mold (WM) Sclerotinia sclerotiorum, are also destructive diseases attacking common bean. Bean common mosaic virus is also one of most major virus disease. Resistance genes (QTLs and major genes) to three bacterial (CBB, BBS, and HB), three fungal (WB, rust, and WM), and one viral pathogen (BCMV) were previously mapped in two common bean populations (BAC 6 × HT 7719 and Belneb RR-1 × A55). The objective of this research was to use an integrated RAPD map of the two populations to compare the positions and effect of resistance QTL in common bean. Results indicate that two chromosomal regions associated with QTL for CBB resistance mapped in both populations. The same chromosomal regions associated with QTL for disease resistance to different pathogens or same pathogens were detected in the integrated population.

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