1
|
Li J, Dai H, Bashir A, Wang Z, An Y, Yu X, Xu L, Li L. Nematicidal activity and action mode of a methyl-accepting chemotaxis protein from Pseudomonas syringae against Caenorhabditis elegans. Heliyon 2024; 10:e30366. [PMID: 38707475 PMCID: PMC11068812 DOI: 10.1016/j.heliyon.2024.e30366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 05/07/2024] Open
Abstract
The conventional phytopathogen Pseudomonas syringae reportedly possesses several virulence determinants against Caenorhabditis elegans; however, their action mechanisms remain elusive. This study reports the nematicidal activity and action receptor of a methyl-accepting chemotaxis protein (MCP03) of a wild-type P. syringae MB03 against C. elegans. Purified MCP03 exhibited nematicidal toxicity against C. elegans at a half-lethal concentration of 124.4 μg mL-1, alongside detrimental effects on the growth and brood size of C. elegans. Additionally, MCP03-treated worms exhibited severe pathological destruction of the intestine and depressed wrinkles of the cuticle. Yeast two-hybrid assays identified a subunit of COP9 signalosome, namely CSN-5, which functioned as an MCP03 action receptor. In vitro pull-down verified the binding interaction between MCP03 and CSN-5. RNA interference assays confirmed that MCP03 antagonizes CSN-5, thereby adversely affecting the brood size and cuticle integrity of C. elegans. Following MCP03 infection, the expression of genes related to reproduction, growth, and cuticle formation, such as kgb-1, unc-98, and col-117, was considerably downregulated, indicating pathological changes in MCP03-treated nematodes. Therefore, we proposed that MCP03 antagonizes CSN-5, causing lethality as well as detrimental effects on the fertility, growth, and morphogenesis of C. elegans, which can provide new insights into the signaling pathways and mechanisms underlying the nematicidal action of MCP03 toward C. elegans.
Collapse
Affiliation(s)
- Jiaoqing Li
- Guangdong Provincial Key Laboratory of Conservation and Precision Utilization of Characteristic Agricultural Resources in Mountainous Areas, School of Life Sciences, Jiaying University, Meizhou 514015, China
| | - Haiyan Dai
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Anum Bashir
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhiyong Wang
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yimin An
- Pomelo Engineering Technology Center, School of Life Sciences, Jiaying University, Meizhou 514015, China
| | - Xun Yu
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Liangzheng Xu
- Guangdong Provincial Key Laboratory of Conservation and Precision Utilization of Characteristic Agricultural Resources in Mountainous Areas, School of Life Sciences, Jiaying University, Meizhou 514015, China
| | - Lin Li
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| |
Collapse
|
2
|
Zhao Y, Yuan Z, Wang S, Wang H, Chao Y, Sederoff RR, Sederoff H, Yan H, Pan J, Peng M, Wu D, Borriss R, Niu B. Gene sdaB Is Involved in the Nematocidal Activity of Enterobacter ludwigii AA4 Against the Pine Wood Nematode Bursaphelenchus xylophilus. Front Microbiol 2022; 13:870519. [PMID: 35602027 PMCID: PMC9121001 DOI: 10.3389/fmicb.2022.870519] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 03/25/2022] [Indexed: 11/13/2022] Open
Abstract
Bursaphelenchus xylophilus, a plant parasitic nematode, is the causal agent of pine wilt, a devastating forest tree disease. Essentially, no efficient methods for controlling B. xylophilus and pine wilt disease have yet been developed. Enterobacter ludwigii AA4, isolated from the root of maize, has powerful nematocidal activity against B. xylophilus in a new in vitro dye exclusion test. The corrected mortality of the B. xylophilus treated by E. ludwigii AA4 or its cell extract reached 98.3 and 98.6%, respectively. Morphological changes in B. xylophilus treated with a cell extract from strain AA4 suggested that the death of B. xylophilus might be caused by an increased number of vacuoles in non-apoptotic cell death and the damage to tissues of the nematodes. In a greenhouse test, the disease index of the seedlings of Scots pine (Pinus sylvestris) treated with the cells of strain AA4 plus B. xylophilus or those treated by AA4 cell extract plus B. xylophilus was 38.2 and 30.3, respectively, was significantly lower than 92.5 in the control plants treated with distilled water and B. xylophilus. We created a sdaB gene knockout in strain AA4 by deleting the gene that was putatively encoding the beta-subunit of L-serine dehydratase through Red homologous recombination. The nematocidal and disease-suppressing activities of the knockout strain were remarkably impaired. Finally, we revealed a robust colonization of P. sylvestris seedling needles by E. ludwigii AA4, which is supposed to contribute to the disease-controlling efficacy of strain AA4. Therefore, E. ludwigii AA4 has significant potential to serve as an agent for the biological control of pine wilt disease caused by B. xylophilus.
Collapse
Affiliation(s)
- Yu Zhao
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
| | - Zhibo Yuan
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
| | - Shuang Wang
- Administrative Office of the Summer Palace, Beijing Municipal Administration Center of Parks, Beijing, China
| | - Haoyu Wang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
| | - Yanjie Chao
- The Center for Microbes, Development and Health (CMDH), Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
| | - Ronald R. Sederoff
- Forest Biotechnology Group, Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, NC, United States
| | - Heike Sederoff
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, United States
| | - He Yan
- Center for Biological Disaster Prevention and Control, National Forestry and Grassland Administration, Shenyang, China
| | - Jialiang Pan
- Center for Biological Disaster Prevention and Control, National Forestry and Grassland Administration, Shenyang, China
| | - Mu Peng
- College of Biological Science and Technology, Hubei Minzu University, Enshi, China
| | - Di Wu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
| | - Rainer Borriss
- Nord Reet UG, Greifswald, Germany
- Institute of Marine Biotechnology e.V. (IMaB), Greifswald, Germany
- *Correspondence: Rainer Borriss,
| | - Ben Niu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
- College of Life Science, Northeast Forestry University, Harbin, China
- Ben Niu,
| |
Collapse
|
3
|
Chalivendra S. Microbial Toxins in Insect and Nematode Pest Biocontrol. Int J Mol Sci 2021; 22:ijms22147657. [PMID: 34299280 PMCID: PMC8303606 DOI: 10.3390/ijms22147657] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/09/2021] [Accepted: 07/15/2021] [Indexed: 12/24/2022] Open
Abstract
Invertebrate pests, such as insects and nematodes, not only cause or transmit human and livestock diseases but also impose serious crop losses by direct injury as well as vectoring pathogenic microbes. The damage is global but greater in developing countries, where human health and food security are more at risk. Although synthetic pesticides have been in use, biological control measures offer advantages via their biodegradability, environmental safety and precise targeting. This is amply demonstrated by the successful and widespread use of Bacillusthuringiensis to control mosquitos and many plant pests, the latter by the transgenic expression of insecticidal proteins from B. thuringiensis in crop plants. Here, I discuss the prospects of using bacterial and fungal toxins for pest control, including the molecular basis of their biocidal activity.
Collapse
|
4
|
Chauhan VK, Dhania NK, Lokya V, Bhuvanachandra B, Padmasree K, Dutta-Gupta A. Midgut aminopeptidase N expression profile in castor semilooper (Achaea janata) during sublethal Cry toxin exposure. J Biosci 2021. [DOI: 10.1007/s12038-021-00148-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
5
|
West MEJ, Moore PA. Bt Proteins Exacerbate Negative Growth Effects in Juvenile Rusty (F. rusticus) Crayfish Fed Corn Diet. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2019; 77:452-460. [PMID: 31451889 DOI: 10.1007/s00244-019-00664-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 08/17/2019] [Indexed: 06/10/2023]
Abstract
The adoption of genetically modified (GM) crops has occurred rapidly in the United States. The transfer of GM corn byproducts from agricultural fields to nearby streams after harvest is significant and occurs well into the post-harvest year. These corn leaves, stems, and cobs then become a detrital food source for organisms, such as shredders in the stream ecosystem. Considering that the nontarget effects of Bt corn have been observed in some terrestrial organisms, we assessed whether Bt toxins affect an important aquatic organism, juvenile F. rusticus crayfish. Juvenile crayfish were fed six distinct diet treatments: two varieties of Bt corn, two non-Bt controls of herbicide tolerant corn, and two controls: fish gelatin and river detritus. Juveniles were fed these diets while housed in flow-through artificial streams that received natural stream water from a local source. Specific growth rate and survivorship of the crayfish were measured throughout the study. Juveniles fed corn diets grew significantly less and had reduced survival compared with juveniles fed fish gelatin or river detritus diets. Furthermore, juveniles fed one Bt variety of corn (VT Triple Pro®) exhibited significantly less growth than those fed one of the herbicide tolerant varieties (Roundup Ready 2®). Our study shows that corn inputs to streams may be detrimental to the growth and survivorship of juvenile crayfish and that certain Bt varieties may exacerbate these negative effects. These effects on crayfish will have repercussions for the entire ecosystem, because crayfish are conduits of energy between many trophic levels.
Collapse
Affiliation(s)
- Molly E J West
- Laboratory for Sensory Ecology, Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43403, USA
- University of Michigan Biological Station, Pellston, MI, 49769, USA
| | - Paul A Moore
- Laboratory for Sensory Ecology, Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43403, USA.
- University of Michigan Biological Station, Pellston, MI, 49769, USA.
| |
Collapse
|
6
|
Temperature stress and insect immunity. J Therm Biol 2017; 68:96-103. [DOI: 10.1016/j.jtherbio.2016.12.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 12/01/2016] [Accepted: 12/05/2016] [Indexed: 11/18/2022]
|
7
|
Chattopadhyay P, Banerjee G, Mukherjee S. Recent trends of modern bacterial insecticides for pest control practice in integrated crop management system. 3 Biotech 2017; 7:60. [PMID: 28444605 DOI: 10.1007/s13205-017-0717-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 03/31/2017] [Indexed: 10/19/2022] Open
Abstract
Food security and safety are the major concern in ever expanding human population on the planet earth. Each and every year insect pests cause a serious damage in agricultural field that cost billions of dollars annually to farmers. The loss in term of productivity and high cost of chemical pesticides enhance the production cost. Irrespective use of chemical pesticides (such as Benzene hexachloride, Endosulfan, Aldicarb, and Fenobucarb) in agricultural field raised several types of environmental issues. Furthermore, continuous use of chemical pesticides creates a selective pressure which helps in emerging of resistance pest. These excess chemical pesticide residues also contaminate the environment including the soil and water. Therefore, the biological control of insect pest in the agricultural field gains more importance due to food safety and environment friendly nature. In this regard, bacterial insecticides offer better alternative to chemical pesticides. It not only helps to establish food security through fighting against insect pests but also ensure the food safety. In this review, we have categorized insect pests and the corresponding bacterial insecticides, and critically analyzed the importance and mode of action of bacterial pesticides. We also have summarized the use of biopesticides in integrated pest management system. We have tried to focus the future research area in this field for the upcoming scientists.
Collapse
|
8
|
Nanoscale imaging and characterization of Caenorhabditis elegans epicuticle using atomic force microscopy. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2017; 13:483-491. [DOI: 10.1016/j.nano.2016.10.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 09/14/2016] [Accepted: 10/07/2016] [Indexed: 12/21/2022]
|
9
|
Then C, Bauer-Panskus A. Possible health impacts of Bt toxins and residues from spraying with complementary herbicides in genetically engineered soybeans and risk assessment as performed by the European Food Safety Authority EFSA. ENVIRONMENTAL SCIENCES EUROPE 2017; 29:1. [PMID: 28133586 PMCID: PMC5236067 DOI: 10.1186/s12302-016-0099-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 12/15/2016] [Indexed: 05/05/2023]
Abstract
BACKGROUND MON89788 was the first genetically engineered soybean worldwide to express a Bt toxin. Under the brand name Intacta, Monsanto subsequently engineered a stacked trait soybean using MON89788 and MON87701-this stacked soybean expresses an insecticidal toxin and is, in addition, tolerant to glyphosate. After undergoing risk assessment by the European Food Safety Authority (EFSA), the stacked event was authorised for import into the EU in June 2012, including for use in food and feed. This review discusses the health risks associated with Bt toxins present in these genetically engineered plants and the residues left from spraying with the complementary herbicide. RESULTS We have compared the opinion published by EFSA [1] with findings from other publications in the scientific literature. It is evident that there are several issues that EFSA did not consider in detail and which will need further assessment: (1) There are potential combinatorial effects between plant components and other impact factors that might enhance toxicity. (2) It is known that Bt toxins have immunogenic properties; since soybeans naturally contain many allergens, these immunogenic properties raise specific questions. (3) Fully evaluated and reliable protocols for measuring the Bt concentration in the plants are needed, in addition to a comprehensive set of data on gene expression under varying environmental conditions. (4) Specific attention should be paid to the herbicide residues and their interaction with Bt toxins. CONCLUSIONS The case of the Intacta soybeans highlights several regulatory problems with Bt soybean plants in the EU. Moreover, many of the issues raised also concern other genetically engineered plants that express insecticidal proteins, or are engineered to be resistant to herbicides, or have those two types of traits combined in stacked events. It remains a matter of debate whether the standards currently applied by the risk assessor, EFSA, and the risk manager, the EU Commission, meet the standards for risk analysis defined in EU regulations such as 1829/2003 and Directive 2001/18. While this publication cannot provide a final conclusion, it allows the development of some robust hypotheses that should be investigated further before such plants can be considered to be safe for health and the environment. In general, the concept of comparative risk assessment needs some major revision. Priority should be given to developing more targeted approaches. As shown in the case of Intacta, these approaches should include: (i) systematic investigation of interactions between the plant genome and environmental stressors as well as their impact on gene expression and plant composition; (ii) detailed investigations of the toxicity of Bt toxins; (iii) assessment of combinatorial effects taking into account long-term effects and the residues from spraying with complementary herbicides; (iv) investigation into the impact on the immune and hormonal systems and (v) investigation of the impact on the intestinal microbiome after consumption. Further and in general, stacked events displaying a high degree of complexity due to possible interactions should not undergo a lower level of risk assessment than the parental plants.
Collapse
Affiliation(s)
- Christoph Then
- Testbiotech, Institute for Independent Impact Assessment in Biotechnology, Frohschammerstr. 14, 80807 Munich, Germany
| | - Andreas Bauer-Panskus
- Testbiotech, Institute for Independent Impact Assessment in Biotechnology, Frohschammerstr. 14, 80807 Munich, Germany
| |
Collapse
|
10
|
Hung TP, Truong LV, Binh ND, Frutos R, Quiquampoix H, Staunton S. Fate of insecticidal Bacillus thuringiensis Cry protein in soil: differences between purified toxin and biopesticide formulation. PEST MANAGEMENT SCIENCE 2016; 72:2247-2253. [PMID: 26910634 DOI: 10.1002/ps.4262] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 02/05/2016] [Accepted: 02/17/2016] [Indexed: 06/05/2023]
Abstract
BACKGROUND Bacillus thuringiensis produces insecticidal proteins known as Cry, and its efficiency and absence of side effects make it the most widely used biopesticide. There is little information on the role of soils in the fate of Cry proteins from commercial biopesticide formulations, unlike toxins from genetically modified crops, which have been intensively studied in recent years. The persistence of Cry in soil was followed under field and laboratory conditions. RESULTS Sunlight accelerated loss of detectable Cry under laboratory conditions, but little effect of shade was observed under field conditions. The half-life of biopesticide proteins in soil under natural conditions was about 1 week. Strong temperature effects were observed, but they differed for biopesticide and purified protein, indicating different limiting steps. CONCLUSION For the biopesticide, the observed decline in detectable protein was due to biological factors, possibly including the germination of B. thuringiensis spores, and was favoured by higher temperature. In contrast, for purified proteins, the decline in detectable protein was slower at low temperature, probably because the conformational changes of the soil-adsorbed protein, which cause fixation and hence reduced extraction efficiency, are temperature dependent. © 2016 Society of Chemical Industry.
Collapse
Affiliation(s)
- Truong Phuc Hung
- INRA, UMR Eco & Sols, INRA-IRD-Cirad-SupAgro, Montpellier, France
- Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - Le Van Truong
- INRA, UMR Eco & Sols, INRA-IRD-Cirad-SupAgro, Montpellier, France
- Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - Ngo Dinh Binh
- Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - Roger Frutos
- Université de Montpellier, UMR 5236, CPBS, CNRS-Université de Montpellier, Montpellier, France
- Cirad, UMR17, Intertryp, Cirad-IRD, TA-A17/G, Montpellier, France
| | | | - Siobhán Staunton
- INRA, UMR Eco & Sols, INRA-IRD-Cirad-SupAgro, Montpellier, France.
| |
Collapse
|
11
|
Bacillus cereus strain S2 shows high nematicidal activity against Meloidogyne incognita by producing sphingosine. Sci Rep 2016; 6:28756. [PMID: 27338781 PMCID: PMC4919635 DOI: 10.1038/srep28756] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 06/08/2016] [Indexed: 01/22/2023] Open
Abstract
Plant-parasitic nematodes cause serious crop losses worldwidely. This study intended to discover the antagonistic mechanism of Bacillus cereus strain S2 against Meloidogyne incognita. Treatment with B. cereus strain S2 resulted in a mortality of 77.89% to Caenorhabditis elegans (a model organism) and 90.96% to M. incognita. In pot experiment, control efficiency of B. cereus S2 culture or supernatants were 81.36% and 67.42% towards M. incognita, respectively. In field experiment, control efficiency was 58.97% towards M. incognita. Nematicidal substances were isolated from culture supernatant of B. cereus S2 by polarity gradient extraction, silica gel column chromatography and HPLC. Two nematicidal compounds were identified as C16 sphingosine and phytosphingosine by LC-MS. The median lethal concentration of sphingosine was determined as 0.64 μg/ml. Sphingosine could obviously inhibit reproduction of C. elegans, with an inhibition rate of 42.72% for 24 h. After treatment with sphingosine, ROS was induced in intestinal tract, and genital area disappeared in nematode. Furthermore, B. cereus S2 could induce systemic resistance in tomato, and enhance activity of defense-related enzymes for biocontrol of M. incognita. This study demonstrates the nematicidal activity of B. cereus and its product sphingosine, as well provides a possibility for biocontrol of M. incognita.
Collapse
|
12
|
Keiser CN, Shearer TA, DeMarco AE, Brittingham HA, Knutson KA, Kuo C, Zhao K, Pruitt JN. Cuticular bacteria appear detrimental to social spiders in mixed but not monoculture exposure. Curr Zool 2016; 62:377-384. [PMID: 29491926 PMCID: PMC5829440 DOI: 10.1093/cz/zow015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/22/2015] [Indexed: 12/15/2022] Open
Abstract
Much of an animal’s health status, life history, and behavior are dictated by
interactions with its endogenous and exogenous bacterial communities. Unfortunately,
interactions between hosts and members of their resident bacterial community are often
ignored in animal behavior and behavioral ecology. Here, we aim to identify the nature of
host–microbe interactions in a nonmodel organism, the African social spider
Stegodyphus dumicola. We collected and identified bacteria from the
cuticles of spiders in situ and then exposed spiders to bacterial
monocultures cultures via topical application or injection. We also topically inoculated
spiders with a concomitant “cocktail” of bacteria and measured the behavior of spiders
daily for 24 days after inoculation. Lastly, we collected and identified bacteria from the
cuticles of prey items in the capture webs of spiders, and then fed spiders domestic
crickets which had been injected with these bacteria. We also injected 1 species of
prey-borne bacteria into the hemolymph of spiders. Only Bacillus
thuringiensis caused increased mortality when injected into the hemolymph of
spiders, whereas no bacterial monocultures caused increased mortality when applied
topically, relative to control solutions. However, a bacterial cocktail of cuticular
bacteria caused weight loss and mortality when applied topically, yet did not detectibly
alter spider behavior. Consuming prey injected with prey-borne bacteria was associated
with an elongated lifespan in spiders. Thus, indirect evidence from multiple experiments
suggests that the effects of these bacteria on spider survivorship appear contingent on
their mode of colonization and whether they are applied in monoculture or within a mixed
cocktail. We urge that follow-up studies should test these host–microbe interactions
across different social contexts to determine the role that microbes play in colony
performance.
Collapse
Affiliation(s)
- Carl N Keiser
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260 USA
| | - Taylor A Shearer
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260 USA
| | - Alexander E DeMarco
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260 USA
| | - Hayley A Brittingham
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260 USA
| | - Karen A Knutson
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260 USA
| | - Candice Kuo
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260 USA
| | - Katherine Zhao
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260 USA
| | - Jonathan N Pruitt
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260 USA
| |
Collapse
|
13
|
Hung TP, Truong LV, Binh ND, Frutos R, Quiquampoix H, Staunton S. Persistence of detectable insecticidal proteins from Bacillus thuringiensis (Cry) and toxicity after adsorption on contrasting soils. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 208:318-325. [PMID: 26549751 DOI: 10.1016/j.envpol.2015.09.046] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 09/19/2015] [Accepted: 09/21/2015] [Indexed: 06/05/2023]
Abstract
Insecticidal Cry, or Bt, proteins are produced by the soil-endemic bacterium, Bacillus thuringiensis and some genetically modified crops. Their environmental fate depends on interactions with soil. Little is known about the toxicity of adsorbed proteins and the change in toxicity over time. We incubated Cry1Ac and Cry2A in contrasting soils subjected to different treatments to inhibit microbial activity. The toxin was chemically extracted and immunoassayed. Manduca sexta was the target insect for biotests. Extractable toxin decreased during incubation for up to four weeks. Toxicity of Cry1Ac was maintained in the adsorbed state, but lost after 2 weeks incubation at 25 °C. The decline in extractable protein and toxicity were much slower at 4 °C with no significant effect of soil sterilization. The major driving force for decline may be time-dependent fixation of adsorbed protein, leading to a decrease in the extraction yield in vitro, paralleled by decreasing solubilisation in the larval gut.
Collapse
Affiliation(s)
- T P Hung
- INRA, UMR Eco&Sols, INRA-IRD-Cirad-SupAgro, 2 Place Viala, 34060 Montpellier, France; Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Hanoi, Viet Nam
| | - L V Truong
- INRA, UMR Eco&Sols, INRA-IRD-Cirad-SupAgro, 2 Place Viala, 34060 Montpellier, France; Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Hanoi, Viet Nam
| | - N D Binh
- Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Hanoi, Viet Nam
| | - R Frutos
- Cirad, UMR17, Intertryp, Cirad-IRD, TA-A17/G, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France; Université de Montpellier, UMR 5236-CPBS, CNRS-Université de Montpellier, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - H Quiquampoix
- INRA, UMR Eco&Sols, INRA-IRD-Cirad-SupAgro, 2 Place Viala, 34060 Montpellier, France
| | - S Staunton
- INRA, UMR Eco&Sols, INRA-IRD-Cirad-SupAgro, 2 Place Viala, 34060 Montpellier, France.
| |
Collapse
|
14
|
Glaum P, Vandermeer J. Potential for and consequences of naturalized Bt products: Qualitative dynamics from indirect intransitivities. Ecol Modell 2015. [DOI: 10.1016/j.ecolmodel.2014.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
15
|
Ferreira Holderbaum D, Cuhra M, Wickson F, Orth AI, Nodari RO, Bøhn T. Chronic Responses of Daphnia magna Under Dietary Exposure to Leaves of a Transgenic (Event MON810) Bt-Maize Hybrid and its Conventional Near-Isoline. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2015; 78:993-1007. [PMID: 26262442 PMCID: PMC4566889 DOI: 10.1080/15287394.2015.1037877] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 04/01/2015] [Indexed: 05/29/2023]
Abstract
Insect resistance is the second most common trait globally in cultivated genetically modified (GM) plants. Resistance is usually obtained by introducing into the plant's genome genes from the bacterium Bacillus thuringiensis (Bt) coding for insecticidal proteins (Cry proteins or toxins) that target insect pests. The aim of this study was to examine the hypothesis that a chronic, high-dose dietary exposure to leaves of a Bt-maize hybrid (GM event MON810, expressing a transgenic or recombinant Cry1Ab toxin), exerted no adverse effects on fitness parameters of the aquatic nontarget organism Daphnia magna (water flea) when compared to an identical control diet based on leaves of the non-GM near-isoline. Cry1Ab was immunologically detected and quantified in GM maize leaf material used for Daphnia feed. A 69-kD protein near Bt's active core-toxin size and a 34-kD protein were identified. The D. magna bioassay showed a resource allocation to production of resting eggs and early fecundity in D. magna fed GM maize, with adverse effects for body size and fecundity later in life. This is the first study to examine GM-plant leaf material in the D. magna model, and provides of negative fitness effects of a MON810 maize hybrid in a nontarget model organism under chronic, high dietary exposure. Based upon these results, it is postulated that the observed transgenic proteins exert a nontarget effect in D. magna and/or unintended changes were produced in the maize genome/metabolome by the transformation process, producing a nutritional difference between GM-maize and non-GM near-isoline.
Collapse
Affiliation(s)
- Daniel Ferreira Holderbaum
- Federal University of Santa Catarina, Graduate Program in Plant Genetic Resources, Florianópolis, Brazil
- GenØk, Centre for Biosafety, Tromsø, Norway
| | - Marek Cuhra
- GenØk, Centre for Biosafety, Tromsø, Norway
- UIT, The Arctic University of Norway, Faculty of Health Sciences, Tromsø, Norway
| | | | - Afonso Inácio Orth
- Federal University of Santa Catarina, Graduate Program in Plant Genetic Resources, Florianópolis, Brazil
| | - Rubens Onofre Nodari
- Federal University of Santa Catarina, Graduate Program in Plant Genetic Resources, Florianópolis, Brazil
| | - Thomas Bøhn
- GenØk, Centre for Biosafety, Tromsø, Norway
- UIT, The Arctic University of Norway, Faculty of Health Sciences, Tromsø, Norway
| |
Collapse
|
16
|
No adjuvant effect of Bacillus thuringiensis-maize on allergic responses in mice. PLoS One 2014; 9:e103979. [PMID: 25084284 PMCID: PMC4118972 DOI: 10.1371/journal.pone.0103979] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 07/09/2014] [Indexed: 11/19/2022] Open
Abstract
Genetically modified (GM) foods are evaluated carefully for their ability to induce allergic disease. However, few studies have tested the capacity of a GM food to act as an adjuvant, i.e. influencing allergic responses to other unrelated allergens at acute onset and in individuals with pre-existing allergy. We sought to evaluate the effect of short-term feeding of GM Bacillus thuringiensis (Bt)-maize (MON810) on the initiation and relapse of allergic asthma in mice. BALB/c mice were provided a diet containing 33% GM or non-GM maize for up to 34 days either before ovalbumin (OVA)-induced experimental allergic asthma or disease relapse in mice with pre-existing allergy. We observed that GM-maize feeding did not affect OVA-induced eosinophilic airway and lung inflammation, mucus hypersecretion or OVA-specific antibody production at initiation or relapse of allergic asthma. There was no adjuvant effect upon GM-maize consumption on the onset or severity of allergic responses in a mouse model of allergic asthma.
Collapse
|
17
|
Paula DP, Andow DA, Timbó RV, Sujii ER, Pires CSS, Fontes EMG. Uptake and transfer of a Bt toxin by a Lepidoptera to its eggs and effects on its offspring. PLoS One 2014; 9:e95422. [PMID: 24747962 PMCID: PMC3991689 DOI: 10.1371/journal.pone.0095422] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 03/27/2014] [Indexed: 11/30/2022] Open
Abstract
Research on non-target effects of transgenic crop plants has focused primarily on bitrophic, tritrophic and indirect effects of entomotoxins from Bacillus thuringiensis, but little work has considered intergenerational transfer of Cry proteins. This work reports a lepidopteran (Chlosyne lacinia) taking up a Bt entomotoxin when exposed to sublethal or low concentrations, transferring the entomotoxin to eggs, and having adverse effects on the first filial generation (F1) offspring. Two bioassays were conducted using a sublethal concentration of toxin (100.0 ng/µl Cry1Ac) for adults and a concentration equal to the LC10 (2.0 ng/µl Cry1Ac) for larvae. Cry1Ac is the most common entomotoxin expressed in Bt cotton in Brazil. In the adult diet bioassay there was no adverse effect on the parental generation (P0) adults, but the F1 larvae had higher mortality and longer development time compared to F1 larvae of parents that did not ingest Cry1Ac. For the 3rd instar larvae, there was no measurable effect on the P0 larvae, pupae and adults, but the F1 larvae had higher mortality and longer development time. Using chemiluminescent Western Blot, Cry1Ac was detected in F1 eggs laid by P0 butterflies from both bioassays. Our study indicates that, at least for this species and these experimental conditions, a ∼65 kDa insecticidal protein can be taken up and transferred to descendants where it can increase mortality and development time.
Collapse
Affiliation(s)
- Débora Pires Paula
- Department of Biological Control, Embrapa Genetic Resources and Biotechnology, Brasília, DF, Brazil
- * E-mail:
| | - David A. Andow
- Department of Entomology, University of Minnesota, St. Paul, Minnesota, United States of America
| | - Renata Velozo Timbó
- Department of Molecular Biology, University of Brasilia, Brasília, DF, Brazil
| | - Edison R. Sujii
- Department of Biological Control, Embrapa Genetic Resources and Biotechnology, Brasília, DF, Brazil
| | - Carmen S. S. Pires
- Department of Biological Control, Embrapa Genetic Resources and Biotechnology, Brasília, DF, Brazil
| | - Eliana M. G. Fontes
- Department of Biological Control, Embrapa Genetic Resources and Biotechnology, Brasília, DF, Brazil
| |
Collapse
|
18
|
Mode of Action and Specificity of Bacillus thuringiensis Toxins in the Control of Caterpillars and Stink Bugs in Soybean Culture. ISRN MICROBIOLOGY 2014; 2014:135675. [PMID: 24575310 PMCID: PMC3918364 DOI: 10.1155/2014/135675] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 11/26/2013] [Indexed: 01/12/2023]
Abstract
The bacterium Bacillus thuringiensis (Bt) produces delta-endotoxins that possess toxic properties and can be used as biopesticides, as well as a source of genes for the construction of transgenic plants resistant to insects. In Brazil, the introduction of Bt soybean with insecticidal properties to the velvetbean caterpillar, the main insect pest of soybean, has been seen a promising tool in the management of these agroecosystems. However, the increase in stink bug populations in this culture, in various regions of the country, which are not susceptible to the existing genetically modified plants, requires application of chemicals that damage the environment. Little is known about the actual toxicity of Bt to Hemiptera, since these insects present sucking mouthparts, which hamper toxicity assays with artificial diets containing toxins of this bacterium. In recent studies of cytotoxicity with the gut of different hemipterans, susceptibility in the mechanism of action of delta-endotoxins has been demonstrated, which can generate promising subsidies for the control of these insect pests in soybean. This paper aims to review the studies related to the selection, application and mode of action of Bt in the biological control of the major pest of soybean, Anticarsia gemmatalis, and an analysis of advances in research on the use of Bt for control hemipterans.
Collapse
|
19
|
Dual invasion analysis: a general model of novel ecological dynamics due to Bt product and resistant pests in wild settings. THEOR ECOL-NETH 2013. [DOI: 10.1007/s12080-013-0209-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
20
|
Ochoa-Campuzano C, Martínez-Ramírez AC, Contreras E, Rausell C, Real MD. Prohibitin, an essential protein for Colorado potato beetle larval viability, is relevant to Bacillus thuringiensis Cry3Aa toxicity. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2013; 107:299-308. [PMID: 24267691 DOI: 10.1016/j.pestbp.2013.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 09/02/2013] [Accepted: 09/03/2013] [Indexed: 06/02/2023]
Abstract
Bacillus thuringienesis (Bt) Cry toxins constitute the most extensively used environmentally safe biopesticide and their mode of action relies on the interaction of the toxins with membrane proteins in the midgut of susceptible insects that mediate toxicity and insect specificity. Therefore, identification of Bt Cry toxin interacting proteins in the midgut of target insects and understanding their role in toxicity is of great interest to exploit their insecticidal action. Using ligand blot, we demonstrated that Bt Cry3Aa toxin bound to a 30kDa protein in Colorado potato beetle (CPB) larval midgut membrane, identified by sequence homology as prohibitin-1 protein. Prohibitins comprise a highly conserved family of proteins implicated in important cellular processes. We obtained the complete CPB prohibitin-1 DNA coding sequence of 828pb, in silico translated into a 276-amino acid protein. The analysis at the amino acid level showed that the protein contains a prohibitin-homology domain (Band7_prohibitin, cd03401) conserved among prohibitin proteins. A striking feature of the CPB identified prohibitin-1 is the predicted presence of cadherin elements, potential binding sites for Cry toxins described in other Bt susceptible insects. We also showed that CPB prohibitin-1 protein partitioned into both, detergent soluble and insoluble membrane fractions, as well as a prohibitin-2 homologous protein, previously reported to form functional complexes with prohibitin-1 in other organisms. Prohibitin complexes act as membrane scaffolds ensuring the recruitment of membrane proteases to facilitate substrate processing. Accordingly, sequestration of prohibitin-1 by an anti-prohibitin-1 antibody impaired the Cry3Aa toxin inhibition of the proteolytic cleavage of a fluorogenic synthetic substrate of an ADAM-like metalloprotease previously reported to proteolize this toxin. In this work, we also demonstrated that prohibitin-1 RNAi silencing in CPB larvae produced deleterious effects and together with a LD50 Cry3Aa toxin treatment resulted in a highly efficient short term response since 100% larval mortality was achieved just 5days after toxin challenge. Therefore, the combination of prohibitin RNAi and Cry toxin reveals as an effective strategy to improve crop protection.
Collapse
Affiliation(s)
- Camila Ochoa-Campuzano
- Departamento de Genética, Facultad de Ciencias Biológicas, Universidad de Valencia, Dr. Moliner 50, Burjassot, 46100 Valencia, Spain
| | | | | | | | | |
Collapse
|
21
|
Liu Z, Budiharjo A, Wang P, Shi H, Fang J, Borriss R, Zhang K, Huang X. The highly modified microcin peptide plantazolicin is associated with nematicidal activity of Bacillus amyloliquefaciens FZB42. Appl Microbiol Biotechnol 2013; 97:10081-90. [PMID: 24085393 DOI: 10.1007/s00253-013-5247-5] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 08/19/2013] [Accepted: 08/22/2013] [Indexed: 11/30/2022]
Abstract
Bacillus amyloliquefaciens FZB42 has been shown to stimulate plant growth and to suppress the growth of plant pathogenic organisms including nematodes. However, the mechanism underlying its effect against nematodes remains unknown. In this study, we screened a random mutant library of B. amyloliquefaciens FZB42 generated by the mariner transposon TnYLB-1 and identified a mutant strain F5 with attenuated nematicidal activity. Reversible polymerase chain reaction revealed that three candidate genes RAMB_007470, yhdY, and prkA that were disrupted by the transposon in strain F5 potentially contributed to its decreased nematicidal activity. Bioassay of mutants impaired in the three candidate genes demonstrated that directed deletion of gene RBAM_007470 resulted in loss of nematicidal activity comparable with that of the F5 triple mutant. RBAM_007470 has been reported as being involved in biosynthesis of plantazolicin, a thiazole/oxazole-modified microcin with hitherto unknown function. Electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) analyses of surface extracts revealed that plantazolicin bearing a molecular weight of 1,354 Da was present in wild-type B. amyloliquefaciens FZB42, but absent in the ΔRABM_007470 mutant. Furthermore, bioassay of the organic extract containing plantazolicin also showed a moderate nematicidal activity. We conclude that a novel gene RBAM_007470 and its related metabolite are involved in the antagonistic effect exerted by B. amyloliquefaciens FZB42 against nematodes.
Collapse
Affiliation(s)
- Zhongzhong Liu
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, China
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Wojda I, Taszłow P. Heat shock affects host-pathogen interaction in Galleria mellonella infected with Bacillus thuringiensis. JOURNAL OF INSECT PHYSIOLOGY 2013; 59:894-905. [PMID: 23834825 DOI: 10.1016/j.jinsphys.2013.06.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 06/23/2013] [Accepted: 06/27/2013] [Indexed: 06/02/2023]
Abstract
We report that Galleria mellonella larvae exposed to heat shock was more resistant to infection with entomopathogenic bacteria Bacillus thuringiensis. The insects were exposed to a temperature of 40°C for 30 min directly before injection of vegetative bacterial cells. It appeared that the kinetics of the immune response was affected in heat-shocked animals. The infection-induced antimicrobial activity of larval hemolymph was stronger in shocked animals in comparison to the non-shocked ones. Hemolymph proteins of molecular weight below 10 kDa, corresponding to the size of antimicrobial peptides, were responsible for this activity. Furthermore, the transcription level of genes encoding antimicrobial peptides: cecropin, gallerimycin, and galiomycin was increased in the fat bodies of insects exposed to heat shock before infection. On the contrary, the heat-shock treatment did not enhance expression of the metalloproteinase inhibitor-IMPI in the infected animals. The difference in the amount of antimicrobial peptides and, consequently, in the defense activity of insect hemolymph, persisted after the action of bacterial metalloproteinases, which are well-known virulence factors. Furthermore, peptides with antimicrobial activity in the hemolymph of infected larvae pre-exposed to heat shock appeared to be more resistant to proteolytic degradation both in vitro and in vivo. Our results point to the mechanism of cross-protection of thermal stress toward innate immune response.
Collapse
Affiliation(s)
- Iwona Wojda
- Department of Immunobiology, Institute of Biology and Biochemistry, Faculty of Biology and Biotechnology, Akademicka 19, 20-033 Lublin, Poland.
| | | |
Collapse
|
23
|
Höss S, Menzel R, Gessler F, Nguyen HT, Jehle JA, Traunspurger W. Effects of insecticidal crystal proteins (Cry proteins) produced by genetically modified maize (Bt maize) on the nematode Caenorhabditis elegans. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2013; 178:147-151. [PMID: 23570782 DOI: 10.1016/j.envpol.2013.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 02/18/2013] [Accepted: 03/02/2013] [Indexed: 06/02/2023]
Abstract
The genetically modified maize MON89034 × MON88017 expresses different crystal (Cry) proteins with pesticidal activity against the European corn borer (Cry1.105; Cry2Ab2) and the Western corn root worm (Cry3Bb1). Non-target organisms, such as soil nematodes, might be exposed to the Cry proteins that enter the soil in course of crop growing. Therefore, the risk of those proteins for nematodes was assessed by testing their toxic effects on Caenorhabditis elegans. All three insecticidal Cry proteins showed dose-dependent inhibitory effects on C. elegans reproduction (EC50: 0.12-0.38 μmol L(-1)), however, at concentrations that were far above the expected soil concentrations. Moreover, a reduced toxicity was observed when Cry proteins were added jointly. A C. elegans mutant strain deficient for receptors for the nematicidal Cry5B was also resistant against Cry1.105 and Cry2Ab2, suggesting that these Cry proteins bound to the same or similar receptors as nematicidal Cry proteins and thereby affect the reproduction of C. elegans.
Collapse
|
24
|
Contreras E, Schoppmeier M, Real MD, Rausell C. Sodium solute symporter and cadherin proteins act as Bacillus thuringiensis Cry3Ba toxin functional receptors in Tribolium castaneum. J Biol Chem 2013; 288:18013-21. [PMID: 23645668 DOI: 10.1074/jbc.m113.474445] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Understanding how Bacillus thuringiensis (Bt) toxins interact with proteins in the midgut of susceptible coleopteran insects is crucial to fully explain the molecular bases of Bt specificity and insecticidal action. In this work, aminopeptidase N (TcAPN-I), E-cadherin (TcCad1), and sodium solute symporter (TcSSS) have been identified by ligand blot as putative Cry3Ba toxin-binding proteins in Tribolium castaneum (Tc) larvae. RNA interference knockdown of TcCad1 or TcSSS proteins resulted in decreased susceptibility to Cry3Ba toxin, demonstrating the Cry toxin receptor functionality for these proteins. In contrast, TcAPN-I silencing had no effect on Cry3Ba larval toxicity, suggesting that this protein is not relevant in the Cry3Ba toxin mode of action in Tc. Remarkable features of TcSSS protein were the presence of cadherin repeats in its amino acid sequence and that a TcSSS peptide fragment containing a sequence homologous to a binding epitope found in Manduca sexta and Tenebrio molitor Bt cadherin functional receptors enhanced Cry3Ba toxicity. This is the first time that the involvement of a sodium solute symporter protein as a Bt functional receptor has been demonstrated. The role of this novel receptor in Bt toxicity against coleopteran insects together with the lack of receptor functionality of aminopeptidase N proteins might account for some of the differences in toxin specificity between Lepidoptera and Coleoptera insect orders.
Collapse
Affiliation(s)
- Estefanía Contreras
- Departamento de Genética, Facultad de Ciencias Biológicas, Universidad de Valencia, Burjassot 46100, Valencia, Spain
| | | | | | | |
Collapse
|
25
|
Effects of feeding Bt MON810 maize to sows during first gestation and lactation on maternal and offspring health indicators. Br J Nutr 2012; 109:873-81. [DOI: 10.1017/s0007114512002607] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A total of twenty-four sows and their offspring were used in a 20-week study to investigate the effects of feeding GM maize on maternal and offspring health. Sows were fed diets containing GM or non-GM maize from service to the end of lactation. GM maize-fed sows were heavier on day 56 of gestation (P< 0·05). Offspring from sows fed GM maize tended to be lighter at weaning (P= 0·08). Sows fed GM maize tended to have decreased serum total protein (P= 0·08), and increased serum creatinine (P< 0·05) and γ-glutamyltransferase activity (P= 0·07) on day 28 of lactation. Serum urea tended to be decreased on day 110 of gestation in GM maize-fed sows (P= 0·10) and in offspring at birth (P= 0·08). Both platelet count (P= 0·07) and mean cell Hb concentration (MCHC;P= 0·05) were decreased on day 110 of gestation in GM maize-fed sows; however, MCHC tended to be increased in offspring at birth (P= 0·08). There was a minimal effect of feeding GM maize to sows during gestation and lactation on maternal and offspring serum biochemistry and haematology at birth and body weight at weaning.
Collapse
|
26
|
Oh SD, Shin HC, Sohn SI, Lee KJ, Kim HJ, Ryu TH, Lee JY, Park BS, Kweon SJ, Suh SC, Park JS. Evaluation and Assessment of Biosafety for Bacillus thuringiensis (Bt)-transgenic Rice: Responses of Daphnia magna Fed on Bt-transgenic Rice Variety. ACTA ACUST UNITED AC 2011. [DOI: 10.3839/jabc.2011.048] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
27
|
Effects of short-term feeding of Bt MON810 maize on growth performance, organ morphology and function in pigs. Br J Nutr 2011; 107:364-71. [PMID: 21733303 DOI: 10.1017/s0007114511003011] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Male weanling pigs (n 32) with a mean initial body weight of 7·5 kg and a mean weaning age of 28 d were used in a 31 d study to investigate the effects of feeding GM (Bt MON810) maize on growth performance, intestinal histology and organ weight and function. At weaning, the pigs were fed a non-GM starter diet during a 6 d acclimatisation period. The pigs were then blocked by weight and litter ancestry and assigned to diets containing 38·9 % GM (Bt MON810) or non-GM isogenic parent line maize for 31 d. Body weight and feed disappearance were recorded on a weekly basis (n 16/treatment), and the pigs (n 10/treatment) were killed on day 31 for the collection of organ, tissue and blood samples. GM maize-fed pigs consumed more feed than the control pigs during the 31 d study (P < 0·05) and were less efficient at converting feed to gain during days 14-30 (P < 0·01). The kidneys of the pigs fed GM maize tended to be heavier than those of control pigs (P = 0·06); however, no histopathological changes or alterations in blood biochemistry were evident. Small intestinal morphology was not different between treatments. However, duodenal villi of GM maize-fed pigs tended to have fewer goblet cells/μm of villus compared with control pigs (P = 0·10). In conclusion, short-term feeding of Bt MON810 maize to weaned pigs resulted in increased feed consumption, less efficient conversion of feed to gain and a decrease in goblet cells/μm of duodenal villus. There was also a tendency for an increase in kidney weight, but this was not associated with changes in histopathology or blood biochemistry. The biological significance of these findings is currently being clarified in long-term exposure studies in pigs.
Collapse
|
28
|
Manachini B, Arizza V, Parrinello D, Parrinello N. Hemocytes of Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae) and their response to Saccharomyces cerevisiae and Bacillus thuringiensis. J Invertebr Pathol 2010; 106:360-5. [PMID: 21147119 DOI: 10.1016/j.jip.2010.12.006] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 11/23/2010] [Accepted: 12/04/2010] [Indexed: 10/18/2022]
Abstract
Originally from tropical Asia, the Red Palm Weevil (RPW Rhynchophorus ferrugineus (Olivier)) is the most dangerous and deadly pest of many palm trees, and there have been reports of its recent detection in France, Greece and Italy. At present, emphasis is on the development of integrated pest management based on biological control rather than on chemical insecticides, however the success of both systems is often insufficient. In this regard, RPW appears to be one pest that is very difficult to control. Thus investigations into the natural defences of this curculionid are advisable. RPW hemocytes, the main immunocompetent cells in the insect, are described for the first time. We identified five hemocyte cell types from the hemolymph of R. ferrugineus: plasmatocytes (~50%), granulocytes (~35%), prohemocytes (~8%), oenocytes (~4%) and spherulocytes (~3%). SEM observations were also carried out. Some aspects of RPW interaction with non-self organisms, such as Saccharomyces cerevisiae and the entomopathogen bacterium, Bacillus thuringiensis (Bt), are discussed. Plasmatocytes and granulocytes were involved in nodules and capsule formation as well as in the phagocytosis of yeast. The hemocyte response of RPW larvae to sub-lethal doses of commercial products containing Bt was examined. In vivo assays were carried out and Bt in vegetative form was found in the hemolymph. After a diet containing Bt, the number of total hemocytes, mainly plasmatocytes, in the RPW larva hemolymph declined sharply (~12%) and then remained at a low level, while the number of other circulating cells was almost unchanged.
Collapse
Affiliation(s)
- Barbara Manachini
- Dipartimento di Biologia Animale G. Reverberi, Università di Palermo, Palermo, Italy.
| | | | | | | |
Collapse
|
29
|
Perry JN, Devos Y, Arpaia S, Bartsch D, Gathmann A, Hails RS, Kiss J, Lheureux K, Manachini B, Mestdagh S, Neemann G, Ortego F, Schiemann J, Sweet JB. A mathematical model of exposure of non-target Lepidoptera to Bt-maize pollen expressing Cry1Ab within Europe. Proc Biol Sci 2010; 277:1417-25. [PMID: 20053648 PMCID: PMC2871945 DOI: 10.1098/rspb.2009.2091] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Accepted: 12/09/2009] [Indexed: 11/12/2022] Open
Abstract
Genetically modified (GM) maize MON810 expresses a Cry1Ab insecticidal protein, derived from Bacillus thuringiensis (Bt), toxic to lepidopteran target pests such as Ostrinia nubilalis. An environmental risk to non-target Lepidoptera from this GM crop is exposure to harmful amounts of Bt-containing pollen deposited on host plants in or near MON810 fields. An 11-parameter mathematical model analysed exposure of larvae of three non-target species: the butterflies Inachis io (L.), Vanessa atalanta (L.) and moth Plutella xylostella (L.), in 11 representative maize cultivation regions in four European countries. A mortality-dose relationship was integrated with a dose-distance relationship to estimate mortality both within the maize MON810 crop and within the field margin at varying distances from the crop edge. Mortality estimates were adjusted to allow for physical effects; the lack of temporal coincidence between the susceptible larval stage concerned and the period over which maize MON810 pollen is shed; and seven further parameters concerned with maize agronomy and host-plant ecology. Sublethal effects were estimated and allowance made for aggregated pollen deposition. Estimated environmental impact was low: in all regions, the calculated mortality rate for worst-case scenarios was less than one individual in every 1572 for the butterflies and one in 392 for the moth.
Collapse
Affiliation(s)
- J N Perry
- Oaklands Barn, Lug's Lane, Broome, Norfolk NR35 2HT, UK.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Then C. Risk assessment of toxins derived from Bacillus thuringiensis-synergism, efficacy, and selectivity. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2010; 17:791-7. [PMID: 19557450 PMCID: PMC2822905 DOI: 10.1007/s11356-009-0208-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Accepted: 05/28/2009] [Indexed: 05/09/2023]
Abstract
BACKGROUND, AIM, AND SCOPE This review deals with publications concerning the mode of action of Bt proteins and their potential synergism with extrinsic factors. The aim was to assess the impact of those factors especially regarding selectivity and efficacy of Bt toxins and to discuss possible gaps in current risk assessment of genetically engineered plants expressing Bt toxins. MAIN FEATURES The review shows that several extrinsic factors are able to influence the selectivity and efficacy of Bt toxins. The findings are seen as being relevant for risk assessment in Bt plants. This conclusion is derived by discussing current state of knowledge about the mode of action of Bt proteins, unexpected effects on non-target organism, and the way how modified Bt toxins are expressed in genetically engineered plants. RESULTS Several publications have been identified that show that certain factors and synergism can impact efficacy and selectivity of Bt toxins. These extrinsic factors are various and include other Bt toxins or parts from the spore of Bacillus thuringiensis as well as certain enzymes, environmental stress, non-pathogenic microorganisms, and infectious diseases. DISCUSSION Research on the underlying mechanism of observed synergism might help to explain some of the effects found in non-target organisms. In general, possible synergism of Bt toxins with extrinsic factors can be relevant for risk assessment of genetically engineered Bt plants since they expose a modified Bt toxin to the environment under various conditions and over a long period of time. CONCLUSIONS Risk assessment of genetically engineered plants should put into question the general assumption of a high selectivity and a linear dose-response relationship in the toxicity of Bt proteins. Both selectivity and efficacy can be influenced by synergism, which can provoke unexpected and undesired effects in non-target organisms. PERSPECTIVES It is suggested that systematic research be promoted on synergism between Bt toxins and potential extrinsic factors that could impact the spectrum of susceptible organisms. This research should become a prerequisite for risk assessment of Bt plants.
Collapse
Affiliation(s)
- Christoph Then
- Scouting Biotechnology, Frohschammerstr. 14, 80807, Munich, Germany.
| |
Collapse
|
31
|
Applications (EFSA‐GMO‐RX‐MON810) for renewal of authorisation for the continued marketing of (1) existing food and food ingredients produced from genetically modified insect resistant maize MON810; (2) feed consisting of and/or containing maize MON810, including the use of seed for cultivation; and of (3) food and feed additives, and feed materials produced from maize MON810, all under Regulation (EC) No 1829/2003 from Monsanto. EFSA J 2009. [DOI: 10.2903/j.efsa.2009.1149] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|
32
|
Schmidt JEU, Braun CU, Whitehouse LP, Hilbeck A. Effects of activated Bt transgene products (Cry1Ab, Cry3Bb) on immature stages of the ladybird Adalia bipunctata in laboratory ecotoxicity testing. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2009; 56:221-228. [PMID: 18712501 DOI: 10.1007/s00244-008-9191-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2008] [Accepted: 06/16/2008] [Indexed: 05/26/2023]
Abstract
Insect-active Bacillus thuringiensis (Bt) proteins are expressed by several transgenic crop plants to control certain pests, but nontarget organisms such as ladybirds also can be exposed to these proteins in the field. We developed an improved ecotoxicity testing protocol and conducted feeding trials in a laboratory setting to test for possible adverse effects of different concentrations of microbially produced trypsin-activated Cry1Ab and Cry3Bb toxins on the coccinellid Adalia bipunctata. Larval/pupal mortality, development time, and overall body mass accumulation were recorded. Even at the lowest concentration (5 microg/ml), A. bipunctata larvae fed with the lepidopteran-active Cry1Ab toxin exhibited significantly higher mortality than the control group. In experiments with the coleopteran-active Cry3Bb, only a concentration of 25 microg/ml resulted in a marginally significantly higher mortality compared to the control. Both experiments revealed a slight decline in mortality at the highest concentration of 50 microg/ml, though this was statistically significant only in the Cry1Ab treatment. No differences were detected for development time and body mass of newly emerged adults. Dilutions of the expression vector pBD10--used as a control to exclude effects of the toxin production method--at concentrations between 10 and 100 microg/ml revealed no significant effects on either of the studied parameters. This suggests that the increased mortality of larvae in the toxin feeding trials was caused directly by the activated Bt toxins and raises questions regarding their commonly postulated specificity and their mode of action in A. bipunctata. Implications of the reported results for ladybird populations and their biological pest control functions in transgenic crop ecosystems are discussed.
Collapse
Affiliation(s)
- Jörg E U Schmidt
- Institute of Integrative Biology, ETH Zurich, Zurich, Switzerland
| | | | | | | |
Collapse
|
33
|
Bøhn T, Primicerio R, Hessen DO, Traavik T. Reduced fitness of Daphnia magna fed a Bt-transgenic maize variety. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2008; 55:584-92. [PMID: 18347840 DOI: 10.1007/s00244-008-9150-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Accepted: 02/11/2008] [Indexed: 05/15/2023]
Abstract
Genetically modified (GM) maize expressing the Bt-toxin Cry1Ab (Bt-maize) was tested for effects on survival, growth, and reproduction of the water flea Daphnia magna, a crustacean arthropod commonly used as a model organism in ecotoxicological studies. In three repeated experiments, D. magna were fed 100% ground maize in suspension, using either GM or isogenic unmodified (UM) maize. D. magna fed GM-maize showed a significantly reduced fitness performance: The mortality was higher, a lower proportion of females reached sexual maturation, and the overall egg production was lower compared to D. magna fed UM isogenic maize. We conclude that the tested variety of Bt-maize and its UM counterpart do not have the same quality as food sources for this widely used model organism. The combination of a reduced fitness performance combined with earlier onset of reproduction of D. magna fed Bt-maize indicates a toxic effect rather than a lower nutritional value of the GM-maize.
Collapse
Affiliation(s)
- Thomas Bøhn
- Genøk-Centre for Biosafety, The Science Park, P.O. Box 6418, Tromso, 9294, Norway.
| | | | | | | |
Collapse
|
34
|
Bischof LJ, Kao CY, Los FCO, Gonzalez MR, Shen Z, Briggs SP, van der Goot FG, Aroian RV. Activation of the unfolded protein response is required for defenses against bacterial pore-forming toxin in vivo. PLoS Pathog 2008; 4:e1000176. [PMID: 18846208 PMCID: PMC2553261 DOI: 10.1371/journal.ppat.1000176] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Accepted: 09/15/2008] [Indexed: 11/24/2022] Open
Abstract
Pore-forming toxins (PFTs) constitute the single largest class of proteinaceous bacterial virulence factors and are made by many of the most important bacterial pathogens. Host responses to these toxins are complex and poorly understood. We find that the endoplasmic reticulum unfolded protein response (UPR) is activated upon exposure to PFTs both in Caenorhabditis elegans and in mammalian cells. Activation of the UPR is protective in vivo against PFTs since animals that lack either the ire-1-xbp-1 or the atf-6 arms of the UPR are more sensitive to PFT than wild-type animals. The UPR acts directly in the cells targeted by the PFT. Loss of the UPR leads to a normal response against unrelated toxins or a pathogenic bacterium, indicating its PFT-protective role is specific. The p38 mitogen-activated protein (MAPK) kinase pathway has been previously shown to be important for cellular defenses against PFTs. We find here that the UPR is one of the key downstream targets of the p38 MAPK pathway in response to PFT since loss of a functional p38 MAPK pathway leads to a failure of PFT to properly activate the ire-1-xbp-1 arm of the UPR. The UPR-mediated activation and response to PFTs is distinct from the canonical UPR-mediated response to unfolded proteins both in terms of its activation and functional sensitivities. These data demonstrate that the UPR, a fundamental intracellular pathway, can operate in intrinsic cellular defenses against bacterial attack. Pore-forming toxins (PFTs) are bacterial toxins that form holes at the plasma membrane of cells and play an important role in the pathogenesis of many important human pathogens. Although PFTs comprise an important and the single largest class of bacterial protein virulence factors, how cells respond to these toxins has been understudied. We describe here the surprising discovery that a fundamental pathway of eukaryotic cell biology, the endoplasmic reticulum unfolded protein response (UPR), is activated by pore-forming toxins in Caenorhabditis elegans and mammalian cells. We find that this activation is functionally important since loss of either of two of the three arms of UPR leads to hypersensitivity of the nematode to attack by PFTs. The response of the UPR to PFTs can be separated from its response to unfolded proteins both at the level of activation and functional relevance. The response of the UPR to PFTs is dependent on a central pathway of cellular immunity, the p38 MAPK pathway. Our data show that the response of cells to bacterial attack can reveal unanticipated uses and connections between fundamental cell biological pathways.
Collapse
Affiliation(s)
- Larry J. Bischof
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, United States of America
| | - Cheng-Yuan Kao
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, United States of America
| | - Ferdinand C. O. Los
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, United States of America
| | - Manuel R. Gonzalez
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Zhouxin Shen
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, United States of America
| | - Steven P. Briggs
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, United States of America
| | - F. Gisou van der Goot
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Raffi V. Aroian
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, United States of America
- * E-mail:
| |
Collapse
|
35
|
Salehi Jouzani G, Seifinejad A, Saeedizadeh A, Nazarian A, Yousefloo M, Soheilivand S, Mousivand M, Jahangiri R, Yazdani M, Amiri RM, Akbari S. Molecular detection of nematicidal crystalliferousBacillus thuringiensisstrains of Iran and evaluation of their toxicity on free-living and plant-parasitic nematodes. Can J Microbiol 2008; 54:812-22. [DOI: 10.1139/w08-074] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The characterization of nematode-effective strains and cry genes in the Iranian Bacillus thuringiensis (Bt) collection (70 isolates) is presented. Characterization was based on PCR analysis using 12 specific primers for cry5, cry6, cry12, cry13, cry14, and cry21 genes encoding proteins active against nematodes, crystal morphology, and protein band patterns as well as their nematicidal activity on root-knot nematode ( Meloidogyne incognita ) and two free-living nematodes ( Chiloplacus tenuis and Acrobeloides enoplus ). PCR results with primers for these genes showed that 22 isolates (31.5%) contain a minimum of one nematode-active cry gene. Strains containing the cry6 gene were the most abundant and represent 22.8% of the isolates. Bt strains harboring cry14 genes were also abundant (14.2%). cry21 and cry5 genes were less abundant, found in 4.2% and 2.8% of the strains, respectively. In total, six different nematode-active cry gene profiles were detected in this collection. Four isolates did not show the expected PCR product size for cry5, cry6, and cry21 genes; they might contain potentially novel insecticidal crystal protein genes. Twenty-two Bt isolates containing nematode-active cry genes were selected for preliminary bioassays on M. incognita. Based on these bioassays, four isolates were selected for detailed bioassays. Isolates YD5 and KON4 at 2 × 108 CFU/mL concentrations showed 77% and 81% toxicity on M. incognita, respectively. The free-living nematodes C. tenuis and A. enoplus were more susceptible and the highest mortality was observed within 48 h of incubation at all of the concentrations tested. Maximum mortality was recorded for isolates SN1 and KON4 at 2 × 108 CFU/mL concentrations and resulted in 68% and 77% adults deaths of C. tenuis and 68% and 72% for A. enoplus, respectively. Our results showed that PCR is a useful technique for toxicity prediction of nematicidal Bt isolates.
Collapse
Affiliation(s)
- Gholamreza Salehi Jouzani
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Ali Seifinejad
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Abbas Saeedizadeh
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Amin Nazarian
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Majid Yousefloo
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Saeed Soheilivand
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Maryam Mousivand
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Rosa Jahangiri
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Mehdi Yazdani
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Reza Maali Amiri
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| | - Sepideh Akbari
- Department of Microbial Biotechnology and Biosafety, Agricultural Biotechnology Research Institute of Iran, Mahdasht Road, P.O. Box 21525-1897, Karaj, Iran
- Department of Plant Protection, Faculty of Horticultural Sciences and Plant Protection, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
- Department of Agronomy and Plant Breeding, Faculty of Agronomy and Animal Sciences, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
| |
Collapse
|
36
|
Specific activity of a Bacillus thuringiensis strain against Locusta migratoria manilensis. J Invertebr Pathol 2008; 98:169-76. [PMID: 18359040 DOI: 10.1016/j.jip.2008.02.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Revised: 01/12/2008] [Accepted: 02/13/2008] [Indexed: 11/21/2022]
Abstract
Bacillus thuringiensis (Bt) has played an important role in biocontrol of pests. However, insecticidal activity of B. thuringiensis against locusts has been rarely reported. Bt strain BTH-13 exhibiting specific activity to locusts was isolated from a soil sample in China and characterized. Its bipyramidal parasporal crystal is mainly composed of a protein of 129kDa, and produces a mature toxin of 64kDa after activation. The pattern of total DNA from BTH-13 showed a large and three small plasmid bands. Known delta-endotoxin genes, cry1Aa, cry1Ab, cry1Ac, cry1C, cry3, cry4 and cry7Aa were not found from strain BTH-13 by PCR amplification. The sequence analysis of a DNA fragment produced by PCR amplification with degenerate cry-selective primers revealed that the fragment encoded a delta-endotoxin segment, which exhibited some similarity to several Cry proteins (41% of the highest similarity to Cry7Ba1). Toxicity tests were performed against Locusta migratoria manilensis, and the results demonstrated that trypsin-treated sporulated cultures and crystal proteins had high toxicity to larval and adult locusts. Cry toxin of BTH-13 was detected on the midguts of treated locusts using immunofluorescent technology, which confirmed the site of action of the crystal proteins in their toxicity for locusts.
Collapse
|
37
|
Barrows BD, Griffitts JS, Aroian RV. Caenorhabditis elegans carbohydrates in bacterial toxin resistance. Methods Enzymol 2007; 417:340-58. [PMID: 17132513 DOI: 10.1016/s0076-6879(06)17021-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
Abstract
The major virulence factor produced by the bacterium Bacillus thuringiensis (Bt) is a pore-forming toxin called crystal (Cry) toxin, which targets and kills insects and nematodes. To understand how this bacterial toxin interacts with its invertebrate hosts, a genetic screen in C. elegans for nematodes resistant to Bt toxin was carried out. Four of the five genes that mutated to toxin resistance encode glycosyltransferases. These genes were found to participate in the biosynthesis of C. elegans glycosphingolipids. These glycolipids in turn were shown to directly bind Bt toxin. Thus, resistance to Bt toxin in C. elegans can develop as a result of loss of glycolipid receptors for the toxin. Here we describe the isolation of Bt toxin resistance mutants in C. elegans, isolation of C. elegans glycolipids, and their separation by thin-layer chromatography, overlay assays to demonstrate direct binding of Bt toxin to glycolipids, and the purification of specific C. elegans glycolipid species.
Collapse
Affiliation(s)
- Brad D Barrows
- Sections of Cell and Developmental Biology, La Jolla, California, USA
| | | | | |
Collapse
|
38
|
Tian B, Yang J, Zhang KQ. Bacteria used in the biological control of plant-parasitic nematodes: populations, mechanisms of action, and future prospects. FEMS Microbiol Ecol 2007; 61:197-213. [PMID: 17651135 DOI: 10.1111/j.1574-6941.2007.00349.x] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
As a group of important natural enemies of nematode pests, nematophagous bacteria exhibit diverse modes of action: these include parasitizing; producing toxins, antibiotics, or enzymes; competing for nutrients; inducing systemic resistance of plants; and promoting plant health. They act synergistically on nematodes through the direct suppression of nematodes, promoting plant growth, and facilitating the rhizosphere colonization and activity of microbial antagonists. This review details the nematophagous bacteria known to date, including parasitic bacteria, opportunistic parasitic bacteria, rhizobacteria, Cry protein-forming bacteria, endophytic bacteria and symbiotic bacteria. We focus on recent research developments concerning their pathogenic mechanisms at the biochemical and molecular levels. Increased understanding of the molecular basis of the various pathogenic mechanisms of the nematophagous bacteria could potentially enhance their value as effective biological control agents. We also review a number of molecular biological approaches currently used in the study of bacterial pathogenesis in nematodes. We discuss their merits, limitations and potential uses.
Collapse
Affiliation(s)
- Baoyu Tian
- Laboratory for Conservation and Utilization of Bio-resources, Yunnan University, Kunming, China
| | | | | |
Collapse
|
39
|
|
40
|
Lacey LA. Bacillus thuringiensis serovariety israelensis and Bacillus sphaericus for mosquito control. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2007; 23:133-63. [PMID: 17853604 DOI: 10.2987/8756-971x(2007)23[133:btsiab]2.0.co;2] [Citation(s) in RCA: 203] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Since the discovery of Bacillus thuringiensis (Berliner) serovariety israelensis de Barjac (Bti) and efficacious isolates of Bacillus sphaericus Neide, formulations of these bacteria have become the predominant non-chemical means employed for control of mosquito larvae at several locations in the United States and other countries. An overview of developments in the past 20 years is presented in this chapter regarding the toxins of Bti and B. sphaericus, their modes of action, efficacy and factors that affect larvicidal activity, development of resistance, safety, and their roles in integrated mosquito control. The efficacy of Bti formulations has been demonstrated in a variety of habitats against a multitude of species of mosquitoes. B. sphaericus formulations have been utilized predominantly in organically enriched habitats against Culex species, but they are also active in a variety of habitats having low organic enrichment, against numerous species, and across several genera. Stegomyia spp. are not susceptible to practical doses of B. sphaericus formulations. B. sphaericus has been shown to persist longer than Bti in polluted habitats and, under certain circumstances, can recycle in larval cadavers. A disadvantage of B. sphaericus has been the development of resistance in certain populations of Cx. quinquefasciatus Say and Cx. pipiens Linnaeus. Biotic and abiotic factors that influence the larvicidal activity of Bti and B. sphaericus include species of mosquito and their respective feeding strategies, rate of ingestion, age and density of larvae, habitat factors (temperature, solar radiation, depth of water, turbidity, tannin and organic content, presence of vegetation, etc.), formulation factors (type of formulation, toxin content, how effectively the material reaches the target, and settling rate), storage conditions, production factors, means of application and frequency of treatments. Due to their efficacy and relative specificity, both Bti and B. sphaericus can be ideal control agents in integrated programs especially where other biological control agents, environmental management, personal protection and the judicious use of insecticides are combined.
Collapse
Affiliation(s)
- Lawrence A Lacey
- Yakima Agricultural Research Laboratory, USDA-ARS, 5230 Konnowac Pass Road, Wapato, WA 98951, USA
| |
Collapse
|
41
|
Casique-Arroyo G, Bideshi D, Salcedo-Hernández R, Barboza-Corona JE. Development of a recombinant strain of Bacillus thuringiensis subsp. kurstaki HD-73 that produces the endochitinase ChiA74. Antonie van Leeuwenhoek 2006; 92:1-9. [PMID: 17136568 DOI: 10.1007/s10482-006-9127-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2006] [Accepted: 10/16/2006] [Indexed: 12/01/2022]
Abstract
Bacillus thuringiensis subsp. kurstaki HD-73 was transformed with the homologous endochitinase gene chiA74 of B. thuringiensis subsp. kenyae LBIT-82 under the regulation of its own promoter and Shine-Dalgarno sequence. The plasmid, pEHchiA74, which harbors chiA74, was detected by southern blot analysis and showed high segregational stability when the recombinant strain was grown in a medium without antibiotic. The recombinant bacterium transformed with pEHchiA74 showed an improvement in chitinolytic activity three times that of the wild-type strain. Expression of ChiA74 did not have any deleterious effect on the crystal morphology and size, but sporulation and Cry1Ac production in rich medium (nutrient broth with glucose) was reduced by approximately 30%. No significant increase in the toxicity of the transformant bacterium toward Plutella xylostella was detected using the same amount of total protein. However, it is possible that ChiA74 synthesis compensated for the decrease in net Cry1Ac synthesis and toxicity observed with the recombinant strain.
Collapse
Affiliation(s)
- Gabriela Casique-Arroyo
- Departamento de Ingeniería en Alimentos, Instituto de Ciencias Agrícolas, Universidad de Guanajuato, Apartado postal 311, Irapuato, Guanajuato, 36500, Mexico
| | | | | | | |
Collapse
|
42
|
Romão TP, de Melo Chalegre KD, Key S, Ayres CFJ, Fontes de Oliveira CM, de-Melo-Neto OP, Silva-Filha MHNL. A second independent resistance mechanism to Bacillus sphaericus binary toxin targets its alpha-glucosidase receptor in Culex quinquefasciatus. FEBS J 2006; 273:1556-68. [PMID: 16689941 DOI: 10.1111/j.1742-4658.2006.05177.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The entomopathogen Bacillus sphaericus is an important tool for the vector control of Culex sp., and its effectiveness has been validated in field trials. The appearance of resistance to this bacterium, however, remains a threat to its use, and attempts have been made to understand the resistance mechanisms. Previous work showed that the resistance to B. sphaericus in a Culex quinquefasciatus colony is associated with the absence of the approximately 60-kDa binary toxin receptor in larvae midgut microvilli. Here, the gene encoding the C. quinquefasciatus toxin receptor, Cqm1, was cloned and sequenced from a susceptible colony. The deduced amino-acid sequence confirmed its identity as an alpha-glucosidase, and analysis of the corresponding gene sequence from resistant larvae implicated a 19-nucleotide deletion as the basis for resistance. This deletion changes the ORF and originates a premature stop codon, which prevents the synthesis of the full-length Cqm1. Expression of the truncated protein, however, was not detected when whole larvae extracts were probed with antibodies raised against an N-terminal 45-kDa recombinant fragment of Cqm1. It seems that the premature stop codon directs the mutated cqm1 to the nonsense-mediated decay pathway of mRNA degradation. In-gel assays confirmed that a single alpha-glucosidase protein is missing from the resistant colony. Further in vitro affinity assays showed that the recombinant fragment binds to the toxin, and mapped the binding site to the N-terminus of the receptor.
Collapse
Affiliation(s)
- Tatiany Patrícia Romão
- Department of Entomology, Centro de Pesquisas Aggeu Magalhães/Fundação Oswaldo Cruz, Recife-PE, Brazil
| | | | | | | | | | | | | |
Collapse
|