1
|
Palma L, Frizzo L, Kaiser S, Berry C, Caballero P, Bode HB, Del Valle EE. Genome Sequence Analysis of Native Xenorhabdus Strains Isolated from Entomopathogenic Nematodes in Argentina. Toxins (Basel) 2024; 16:108. [PMID: 38393187 PMCID: PMC10892061 DOI: 10.3390/toxins16020108] [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: 01/02/2024] [Revised: 02/05/2024] [Accepted: 02/13/2024] [Indexed: 02/25/2024] Open
Abstract
Entomopathogenic nematodes from the genus Steinernema (Nematoda: Steinernematidae) are capable of causing the rapid killing of insect hosts, facilitated by their association with symbiotic Gram-negative bacteria in the genus Xenorhabdus (Enterobacterales: Morganellaceae), positioning them as interesting candidate tools for the control of insect pests. In spite of this, only a limited number of species from this bacterial genus have been identified from their nematode hosts and their insecticidal properties documented. This study aimed to perform the genome sequence analysis of fourteen Xenorhabdus strains that were isolated from Steinernema nematodes in Argentina. All of the strains were found to be able of killing 7th instar larvae of Galleria mellonella (L.) (Lepidoptera: Pyralidae). Their sequenced genomes harbour 110 putative insecticidal proteins including Tc, Txp, Mcf, Pra/Prb and App homologs, plus other virulence factors such as putative nematocidal proteins, chitinases and secondary metabolite gene clusters for the synthesis of different bioactive compounds. Maximum-likelihood phylogenetic analysis plus average nucleotide identity calculations strongly suggested that three strains should be considered novel species. The species name for strains PSL and Reich (same species according to % ANI) is proposed as Xenorhabdus littoralis sp. nov., whereas strain 12 is proposed as Xenorhabdus santafensis sp. nov. In this work, we present a dual insight into the biocidal potential and diversity of the Xenorhabdus genus, demonstrated by different numbers of putative insecticidal genes and biosynthetic gene clusters, along with a fresh exploration of the species within this genus.
Collapse
Affiliation(s)
- Leopoldo Palma
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Departamento de Genética, Universitat de València, 46100 Burjassot, Spain
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires C1033AAJ, Argentina
- Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica (IMITAB), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Villa María (UNVM), Villa María 1555, Argentina
| | - Laureano Frizzo
- ICIVET Litoral, CONICET-UNL, Departamento de Salud Pública, Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral, Esperanza S3080, Argentina;
| | - Sebastian Kaiser
- Department of Natural Products in Organismic Interactions, Max-Planck-Institute for Terrestrial Microbiology, 35043 Marburg, Germany; (S.K.); (H.B.B.)
- Evolutionary Biochemistry Group, Max-Planck-Institute for Terrestrial Microbiology, 35043 Marburg, Germany
| | - Colin Berry
- Cardiff School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK;
| | - Primitivo Caballero
- Institute for Multidisciplinary Research in Applied Biology, Universidad Pública de Navarra, 31006 Pamplona, Spain;
- Departamento de Investigación y Desarrollo, Bioinsectis SL, Polígono Industrial Mocholi Plaza Cein 5, Nave A14, 31110 Noain, Spain
| | - Helge B. Bode
- Department of Natural Products in Organismic Interactions, Max-Planck-Institute for Terrestrial Microbiology, 35043 Marburg, Germany; (S.K.); (H.B.B.)
- Molecular Biotechnology, Department of Biosciences, Goethe Universität Frankfurt, 60438 Frankfurt, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Phillips University Marburg, 35043 Marburg, Germany
- Department of Chemistry, Phillips University Marburg, 35043 Marburg, Germany
- Senckenberg Gesellschaft für Naturforschung, 60325 Frankfurt, Germany
| | - Eleodoro Eduardo Del Valle
- ICiagro Litoral, CONICET, Facultad de Ciencias Agrarias, Universidad Nacional del Litoral, Kreder 2805, Esperanza S3080, Argentina
| |
Collapse
|
2
|
Abd-Elgawad MMM. Reproduction of Entomopathogenic Nematodes for Use in Pest Control. Methods Mol Biol 2024; 2756:351-382. [PMID: 38427305 DOI: 10.1007/978-1-0716-3638-1_14] [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] [Indexed: 03/02/2024]
Abstract
The growing interest in the use of entomopathogenic nematodes and their symbiotic bacteria as promising biocontrol agents of many arthropod pests and pathogens has created running technologies to expand their use globally. The related laboratory procedures and tests on these nematodes such as their isolation, count, culture, identification, pathogenicity, virulence, and environmental tolerance should form the solid basis for such an expansion with reliable uses. Extensive practical details of such procedures and tests as well as how to identify and overcome the problems associated with these aspects are addressed in this chapter.
Collapse
|
3
|
Raval D, Daley L, Eleftherianos I. Drosophila melanogaster larvae are tolerant to oral infection with the bacterial pathogen Photorhabdus luminescens. MICROPUBLICATION BIOLOGY 2023; 2023:10.17912/micropub.biology.000938. [PMID: 37711508 PMCID: PMC10498274 DOI: 10.17912/micropub.biology.000938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 08/10/2023] [Accepted: 08/28/2023] [Indexed: 09/16/2023]
Abstract
The fruit fly Drosophila melanogaster is an excellent model for dissecting the molecular and functional bases of bacterial pathogenicity and host antibacterial immune response. The Gram-negative bacterium Photorhabdus luminescens is an insect-specific pathogen that forms a mutualistic relationship with the entomopathogenic nematode Heterorhabditis bacteriophora . Here we find that oral infection of D. melanogaster larvae with P. luminescens moderately reduces their survival ability while the bacteria replicate efficiently in the infected insects. This information will contribute towards understanding host gut immunity against potent bacterial pathogens.
Collapse
Affiliation(s)
- Dhaivat Raval
- Department of Biological Sciences, The George Washington University, Washington, DC, USA
| | - Lillia Daley
- Department of Biological Sciences, The George Washington University, Washington, DC, USA
| | - Ioannis Eleftherianos
- Department of Biological Sciences, The George Washington University, Washington, DC, USA
| |
Collapse
|
4
|
Abd-Elgawad MMM. Optimizing Entomopathogenic Nematode Genetics and Applications for the Integrated Management of Horticultural Pests. HORTICULTURAE 2023; 9:865. [DOI: 10.3390/horticulturae9080865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
Entomopathogenic nematodes (EPNs) can kill and recycle in their host populations, which bodes well for EPNs’ exploitation in long-term and safe pest management. However, EPNs’ cost and efficacy need transformational technology to supplant less expensive and more effective but toxic/unhealthy pesticides. A technology that allows for the significant uptake of commercial EPNs should both boost their market suitability and provide genetic improvements. This review provides brief overviews of EPNs’ biology and ecology from the standpoint of pest/pathogen management as a prerequisite for EPN improvements. Understanding the biology and ecology of EPNs, particularly their symbiotic relationships with bacteria, is crucial to their effective use in pest management. This review provides relevant insights into EPN-symbiotic bacteria and the EPN–symbiont complex. The symbiotic relationship between EPNs and bacteria plays a key role in IPM, providing unique advantages. Either of them can be included in mechanisms underlying the various positive sides of plant–insect interactions in emerging integrated pest management (IPM) systems. Recent approaches, in which EPNs can act additively or synergistically with other production inputs in IPM programs, are discussed for further expansion. The simultaneous favorable effects of EPNs and/or their mutualistic bacteria on several pest/pathogen species of crops should be identified. Merits, such as the rapid killing of insect pests, ease of EPN/the symbiont’s mass production and a broad host range, are presented in order to widely disseminate the conditions under which EPN usage can offer a cost-effective and/or value-added technique for IPM. To maximize the effectiveness of EPNs in IPM, various genetic improvement techniques are being explored. Such techniques, along with their merits/demerits and related tools, are reviewed to optimize the common biocontrol usage of EPNs. Examples of genetic improvements to EPNs that allow for their use in transformational technology, such as a cost-effective application technique, increased infectivity, and toleration of unfavorable settings, are given. Proper production practices and genetic techniques should be applied carefully to avoid undesirable results; it is suggested that these are considered on a case-by-case basis. This will enable us to optimize EPN performance based on the given variables.
Collapse
Affiliation(s)
- Mahfouz M. M. Abd-Elgawad
- Plant Pathology Department, Agricultural and Biological Research Institute, National Research Centre, El-Behooth St., Dokki, Giza 12622, Egypt
| |
Collapse
|
5
|
Huber EM, Kreling L, Heinrich AK, Dünnebacke M, Pöthig A, Bode HB, Groll M. A set of closely related methyltransferases for site-specific tailoring of anthraquinone pigments. Structure 2023; 31:573-583.e5. [PMID: 36963398 DOI: 10.1016/j.str.2023.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 02/01/2023] [Accepted: 02/28/2023] [Indexed: 03/26/2023]
Abstract
Modification of the polyketide anthraquinone AQ-256 in the entomopathogenic Photorhabdus luminescens involves several O-methylations, but the biosynthetic gene cluster antA-I lacks corresponding tailoring enzymes. We here describe the identification of five putative, highly homologous O-methyltransferases encoded in the genome of P. luminescens. Activity assays in vitro and deletion experiments in vivo revealed that three of them account for anthraquinone tailoring by producing three monomethylated and two dimethylated species of AQ-256. X-ray structures of all five enzymes indicate high structural and mechanistic similarity. As confirmed by structure-based mutagenesis, a conserved histidine at the active site likely functions as a general base for substrate deprotonation and subsequent methyl transfer in all enzymes. Eight complex structures with AQ-256 as well as mono- and dimethylated derivatives confirm the substrate specificity patterns found in vitro and visualize how single amino acid differences in the active-site pockets impact substrate orientation and govern site-specific methylation.
Collapse
Affiliation(s)
- Eva M Huber
- Technical University of Munich, TUM School of Natural Sciences, Department of Bioscience, Center for Protein Assemblies, Chair of Biochemistry, Ernst-Otto-Fischer-Str. 8, 85748 Garching, Germany.
| | - Lukas Kreling
- Molecular Biotechnology, Department of Biosciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany
| | - Antje K Heinrich
- Molecular Biotechnology, Department of Biosciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany
| | - Maximilian Dünnebacke
- Technical University of Munich, TUM School of Natural Sciences, Department of Bioscience, Center for Protein Assemblies, Chair of Biochemistry, Ernst-Otto-Fischer-Str. 8, 85748 Garching, Germany
| | - Alexander Pöthig
- Technical University of Munich, TUM School of Natural Sciences, Department of Chemistry, Catalysis Research Center, Chair of Inorganic and Metal-Organic Chemistry, Ernst-Otto-Fischer-Str. 1, 85748 Garching, Germany
| | - Helge B Bode
- Molecular Biotechnology, Department of Biosciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany; Department of Natural Products in Organismic Interactions, Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany; Chemical Biology, Department of Chemistry, Phillips University Marburg, 35043 Marburg, Germany; Center for Synthetic Microbiology (SYNMIKRO), Philipps University Marburg, 35043 Marburg, Germany; Senckenberg Gesellschaft für Naturforschung, 60325 Frankfurt am Main, Germany.
| | - Michael Groll
- Technical University of Munich, TUM School of Natural Sciences, Department of Bioscience, Center for Protein Assemblies, Chair of Biochemistry, Ernst-Otto-Fischer-Str. 8, 85748 Garching, Germany.
| |
Collapse
|
6
|
Šunjka D, Mechora Š. Advances in Alternative Measures in Plant Protection. PLANTS (BASEL, SWITZERLAND) 2023; 12:805. [PMID: 36840151 PMCID: PMC9959152 DOI: 10.3390/plants12040805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 01/21/2023] [Indexed: 06/18/2023]
Abstract
Food production, along with the constant demand for higher yields, is an imperative of contemporary agricultural production [...].
Collapse
Affiliation(s)
- Dragana Šunjka
- Faculty of Agriculture, University of Novi Sad, Trg Dositeja Obradovića 8, 21000 Novi Sad, Serbia
| | - Špela Mechora
- Agency for Radwaste Management, Litostrojska 58A, 1000 Ljubljana, Slovenia
| |
Collapse
|
7
|
Kim I, Heryanto C, Eleftherianos I. HETERORHABDITIS BACTERIOPHORA NEMATODES ARE SENSITIVE TO THE BACTERIAL PATHOGEN PHOTORHABDUS ASYMBIOTICA. J Parasitol 2023; 109:11-14. [PMID: 36805240 DOI: 10.1645/22-55] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
The entomopathogenic nematode (EPN) Heterorhabditis bacteriophora infects a wide range of insect hosts with the aid of its mutualistic bacteria Photorhabdus luminescens. While the mutualistic relationship between H. bacteriophora and P. luminescens and the infectivity of the nematode-bacteria complex have been characterized, how nematode fitness is affected by entomopathogenic bacteria existing in association with other EPN species remains poorly understood. In this study, the survival of H. bacteriophora infective juveniles containing or lacking P. luminescens was tested against the entomopathogenic bacteria Xenorhabdus nematophila and Photorhabdus asymbiotica as well as the non-pathogenic Escherichia coli. While X. nematophila and E. coli did not significantly affect the survival of H. bacteriophora, P. asymbiotica exerted a significant effect on nematode survival, particularly on those lacking P. luminescens. These results imply that P. asymbiotica encodes factors that are pathogenic to EPNs. Future efforts will focus on the identification of the bacterial molecular components that induce these effects. This study makes an important contribution to a growing body of research aimed at exploiting the full potential of nematode-bacterial complexes for eliminating noxious insect pests and treating infectious diseases caused by parasitic nematodes.
Collapse
Affiliation(s)
- Irene Kim
- Department of Biological Sciences, The George Washington University, Science and Engineering Hall, 22nd Street NW, Washington, D.C. 20052
| | - Christa Heryanto
- Department of Biological Sciences, The George Washington University, Science and Engineering Hall, 22nd Street NW, Washington, D.C. 20052
| | - Ioannis Eleftherianos
- Department of Biological Sciences, The George Washington University, Science and Engineering Hall, 22nd Street NW, Washington, D.C. 20052
| |
Collapse
|
8
|
Abd-El-Kareem F, Elshahawy IE, Abd-Elgawad MMM. Native bacteria for field biocontrol of black root rot in Egyptian strawberry. BULLETIN OF THE NATIONAL RESEARCH CENTRE 2022; 46:82. [DOI: 10.1186/s42269-022-00775-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 03/20/2022] [Indexed: 09/01/2023]
Abstract
Abstract
Background
Increasing cultivation of strawberry in Egypt has boosted efforts to increase its yield. Biocontrol agents (BCAs) may avoid side effects and health risks caused by chemical fungicides used to control black root rot disease in strawberry. Some BCAs control the disease and augment strawberry yield, but additional research is needed to fit BCAs into emerging control strategies. The impact of six bacterial isolates of Paenibacillus polymyxa and Bacillus brevis on this disease and on berry yield is reported and compared to a common chemical fungicide.
Results
The bacterial isolates reduced the growth of the black root rot causal agents Fusarium solani, Rhizoctonia solani, and Macrophomina phaseolina, in dual culture bioassays. The greatest fungal inhibition was caused by P. polymyxa isolates 1 and 2 and B. brevis isolate 2. They suppressed the growth of F. solani, R. solani, and M. phaseolina by more than 74, 76, and 79%, respectively. Disease severity and incidence were significantly reduced on naturally infected strawberry plants in the field by the six isolates. The best results were obtained by the superior bioassay isolates which suppressed the disease incidence by 73, 77, and 71%, and its severity by 72, 78, and 70%, respectively. Disease suppression by bacteria was comparable to that by fungicide Actamyl. Bacteria surpassed Actamyl with regard to strawberry yield and enhancement of peroxidase and chitinase activities in the leaves.
Conclusions
These isolates are potential benign alternatives to fungicides used against black root rot in strawberry in Egypt. More studies are needed to examine their economic use on a wider scale.
Collapse
|
9
|
Abd-Elgawad MMM. Exploiting Plant-Phytonematode Interactions to Upgrade Safe and Effective Nematode Control. LIFE (BASEL, SWITZERLAND) 2022; 12:life12111916. [PMID: 36431051 PMCID: PMC9693997 DOI: 10.3390/life12111916] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/10/2022] [Accepted: 11/12/2022] [Indexed: 11/19/2022]
Abstract
Plant-parasitic nematodes (PPNs) bring about substantial losses of economic crops globally. With the environmental and health issues facing the use of chemical nematicides, research efforts should focus on providing economically effective and safe control methods. The sound exploitation of plant-PPN interactions is fundamental to such efforts. Initially, proper sampling and extraction techniques should be followed to avoid misleading nematode data. Recent evolutions in plant-PPN interactions can make use of diverse non-molecular and molecular approaches to boost plant defenses. Therefore, PPN control and increasing crop yields through single, sequential, dual-purpose, and simultaneous applications of agricultural inputs, including biocontrol agents, should be seriously attempted, especially within IPM schemes. The use of biologicals would ideally be facilitated by production practices to solve related issues. The full investment of such interactions should employ new views of interdisciplinary specialties in the relevant modern disciplines to optimize the PPN management. Having an accurate grasp of the related molecular events will help in developing tools for PPN control. Nonetheless, the currently investigated molecular plant-PPN interactions favoring plant responses, e.g., resistance genes, RNA interference, marker-assisted selection, proteinase inhibitors, chemo-disruptive peptides, and plant-incorporated protectants, are key factors to expanding reliable management. They may be applied on broader scales for a substantial improvement in crop yields.
Collapse
Affiliation(s)
- Mahfouz M M Abd-Elgawad
- Plant Pathology Department, Agricultural and Biological Research Institute, National Research Centre, El-Behooth St., Dokki, Giza 12622, Egypt
| |
Collapse
|
10
|
Hammam MMA, Abd-El-Khair H, El-Nagdi WMA, Abd-Elgawad MMM. Can Agricultural Practices in Strawberry Fields Induce Plant-Nematode Interaction towards Meloidogyne-Suppressive Soils? Life (Basel) 2022; 12:life12101572. [PMID: 36295007 PMCID: PMC9605673 DOI: 10.3390/life12101572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 09/28/2022] [Accepted: 09/29/2022] [Indexed: 02/17/2023] Open
Abstract
The importance of benign approaches to manage the root-knot nematodes (RKNs, Meloidogyne spp.) in strawberry farms has become more evident with increasing strawberry production and export in Egypt. Therefore, data accumulated on biosolarization and soil amendments to favor beneficial microorganisms and maximize their impact on RKN management are built on a robust historical research foundation and should be exploited. We examined RKN population levels/parameters in three strawberry export governorates, six farms per governorate, to characterize the exact production practices that are responsible for RKN-suppressive soils. All selected farms enjoyed soil biodisinfestation resulting from incorporating organic amendments followed by a plastic cover to suppress soil pathogens. Various safe and inexpensive agricultural practices in the El-Ismailia and El-Beheira governorates were compared to the toxic and expensive fumigants that could eliminate RKNs in the Al-Qalyubia governorate. Two farms at El-Ismailia were of special interest as they ultimately showed almost zero counts of RKNs. The two farms were characterized by incorporating cow manure [containing 0.65% total nitrogen, 21.2 carbon to nitrogen (C/N) ratio] and poultry manure (0.72% total nitrogen, 20.1 C/N ratio) followed by soil solarization via transparent, 80-µm thick plastic covers for 60−65 summer days as pre-strawberry cultivation practices, and similar covers were used after transplanting. Typically, the longer the pre-plant soil solarization period with thicker transparent plastic covers, the better it could suppress the RKN population densities in the tested farms. Their soils were characterized by relatively high pH and low electrical conductivity. The significant development in biocontrol genera/species abundance and frequency could explain the lower (p < 0.0001) RKN population levels inhabiting the farms of El-Ismailia than the El-Beheira governorate. These factors could provide the first approximation of key practices and factors that could collectively contribute to distinguishing and exploiting soil suppressiveness against RKNs. We discussed edaphic properties and production practices that could modulate populations of natural RKN antagonists for sustainable strawberry cultivation.
Collapse
|
11
|
Xenorhabdus spp.: An Overview of the Useful Facets of Mutualistic Bacteria of Entomopathogenic Nematodes. Life (Basel) 2022; 12:life12091360. [PMID: 36143397 PMCID: PMC9503066 DOI: 10.3390/life12091360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/26/2022] [Accepted: 08/26/2022] [Indexed: 12/17/2022] Open
Abstract
Mounting concern over the misuse of chemical pesticides has sparked broad interest for safe and effective alternatives to control plant pests and pathogens. Xenorhabdus bacteria, as pesticidal symbionts of the entomopathogenic nematodes Steinernema species, can contribute to this solution with a treasure trove of insecticidal compounds and an ability to suppress a variety of plant pathogens. As many challenges face sound exploitation of plant–phytonematode interactions, a full useful spectrum of such interactions should address nematicidal activity of Xenorhabdus. Steinernema–Xenorhabdus complex or Xenorhabdus individually should be involved in mechanisms underlying the favorable side of plant–nematode interactions in emerging cropping systems. Using Xenorhabdus bacteria should earnestly be harnessed to control not only phytonematodes, but also other plant pests and pathogens within integrated pest management plans. This review highlights the significance of fitting Xenorhabdus-obtained insecticidal, nematicidal, fungicidal, acaricidal, pharmaceutical, antimicrobial, and toxic compounds into existing, or arising, holistic strategies, for controlling many pests/pathogens. The widespread utilization of Xenorhabdus bacteria, however, has been slow-going, due to costs and some issues with their commercial processing. Yet, advances have been ongoing via further mastering of genome sequencing, discovering more of the beneficial Xenorhabdus species/strains, and their successful experimentations for pest control. Their documented pathogenicity to a broad range of arthropods and pathogens and versatility bode well for useful industrial products. The numerous beneficial traits of Xenorhabdus bacteria can facilitate their integration with other tactics for better pest/disease management programs.
Collapse
|
12
|
Larvicidal activity of Photorhabdus and Xenorhabdus bacteria isolated from insect parasitic nematodes against Aedes aegypti and Aedes albopictus. Acta Trop 2022; 235:106668. [PMID: 36030882 DOI: 10.1016/j.actatropica.2022.106668] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 08/23/2022] [Accepted: 08/24/2022] [Indexed: 01/26/2023]
Abstract
Aedes aegypti and Aedes albopictus are important vectors for several arboviruses such as the dengue virus. The chemical control of Aedes spp., which is usually implemented, affects both humans and the environment. The biological control of Aedes spp. with entomopathogenic bacteria such as Photorhabdus and Xenorhabdus may be an alternative method that can overcome such issues. This study aimed to isolate and identify Photorhabdus and Xenorhabdus bacteria from entomopathogenic nematodes (EPNs) collected in Thailand and evaluate their larvicidal properties in controlling A. aegypti and A. albopictus. Colony morphology and recA sequencing of the 118 symbiotic isolated bacteria indicated that most were P. luminescens subsp. akhurstii and X. stockiae with minor prevalence of P. luminescens subsp. hainanensis, P. asymbiotica subsp. australis, X. indica, X. griffiniae, X. japonica, X. thuongxuanensis, and X. eapokensis . The larvicidal bioassay with the third- and fourth-instar mosquito larvae suggested that a whole-cell suspension of X. griffiniae (bMSN3.3_TH) had the highest efficiency in eradicating A. aegypti and A. albopictus, with 90 ± 3.71% and 81 ± 2.13% mortality, respectively, after 96 h exposure. In contrast, 1% of ethyl acetate extracted from X. indica (bSNK8.5_TH) showed reduced mortality for A. aegypti of only 50 ± 3.66% after 96 h exposure. The results indicate that both X. griffiniae (bMSN3.3_TH) and X. indica (bSNK8.5_TH) could be used as biocontrol agents against Aedes larvae.
Collapse
|
13
|
Erler S, Eckert JH, Steinert M, Alkassab AT. Impact of microorganisms and entomopathogenic nematodes used for plant protection on solitary and social bee pollinators: Host range, specificity, pathogenicity, toxicity, and effects of experimental parameters. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 302:119051. [PMID: 35219794 DOI: 10.1016/j.envpol.2022.119051] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 02/18/2022] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
Pollinating bees are stressed by highly variable environmental conditions, malnutrition, parasites and pathogens, but may also by getting in contact with microorganisms or entomopathogenic nematodes that are used to control plant pests and diseases. While foraging for water, food, or nest material social as well as solitary bees have direct contact or even consume the plant protection product with its active substance (e.g., viruses, bacteria, fungi, etc.). Here, we summarize the results of cage, microcolony, observation hive assays, semi-field and field studies using full-size queen-right colonies. By now, some species and subspecies of the Western and Eastern honey bee (Apis mellifera, A. cerana), few species of bumble bees, very few stingless bee species and only a single species of leafcutter bees have been studied as non-target host organisms. Survival and reproduction are the major criteria that have been evaluated. Especially sublethal effects on the bees' physiology, immune response and metabolisms will be targets of future investigations. By studying infectivity and pathogenic mechanisms, individual strains of the microorganism and impact on different bee species are future challenges, especially under field conditions. Overall, it became evident that honey bees, bumble bees and few stingless bee species may not be suitable surrogate species to make general conclusions for biological mechanisms of bee-microorganism interactions of other social bee species. Solitary bees have been studied on leafcutter bees (Megachile rotundata) only, which shows that this huge group of bees (∼20,000 species worldwide) is right at the beginning to get an insight into the interaction of wild pollinators and microbial plant protection organisms.
Collapse
Affiliation(s)
- Silvio Erler
- Institute for Bee Protection, Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Messeweg 11-12, 38104, Braunschweig, Germany.
| | - Jakob H Eckert
- Institute for Bee Protection, Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Messeweg 11-12, 38104, Braunschweig, Germany; Institute of Microbiology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Michael Steinert
- Institute of Microbiology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Abdulrahim T Alkassab
- Institute for Bee Protection, Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Messeweg 11-12, 38104, Braunschweig, Germany
| |
Collapse
|
14
|
Parihar RD, Dhiman U, Bhushan A, Gupta PK, Gupta P. Heterorhabditis and Photorhabdus Symbiosis: A Natural Mine of Bioactive Compounds. Front Microbiol 2022; 13:790339. [PMID: 35422783 PMCID: PMC9002308 DOI: 10.3389/fmicb.2022.790339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 02/02/2022] [Indexed: 12/12/2022] Open
Abstract
Phylum Nematoda is of great economic importance. It has been a focused area for various research activities in distinct domains across the globe. Among nematodes, there is a group called entomopathogenic nematodes, which has two families that live in symbiotic association with bacteria of genus Xenorhabdus and Photorhabdus, respectively. With the passing years, researchers have isolated a wide array of bioactive compounds from these symbiotically associated nematodes. In this article, we are encapsulating bioactive compounds isolated from members of the family Heterorhabditidae inhabiting Photorhabdus in its gut. Isolated bioactive compounds have shown a wide range of biological activity against deadly pathogens to both plants as well as animals. Some compounds exhibit lethal effects against fungi, bacteria, protozoan, insects, cancerous cell lines, neuroinflammation, etc., with great potency. The main aim of this article is to collect and analyze the importance of nematode and its associated bacteria, isolated secondary metabolites, and their biomedical potential, which can serve as potential leads for further drug discovery.
Collapse
Affiliation(s)
| | | | - Anil Bhushan
- Natural Products and Medicinal Chemistry Division, Council of Scientific and Industrial Research (CSIR)-Indian Institute of Integrative Medicine, Jammu, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Prashant Kumar Gupta
- Department of Horticulture, Rajmata Vijayaraje Scindia Krishi Vishwa Vidyalaya, Gwalior, India
| | - Prasoon Gupta
- Natural Products and Medicinal Chemistry Division, Council of Scientific and Industrial Research (CSIR)-Indian Institute of Integrative Medicine, Jammu, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| |
Collapse
|