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Potential for Bacillus thuringiensis and Other Bacterial Toxins as Biological Control Agents to Combat Dipteran Pests of Medical and Agronomic Importance. Toxins (Basel) 2020; 12:toxins12120773. [PMID: 33291447 PMCID: PMC7762171 DOI: 10.3390/toxins12120773] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 11/24/2020] [Accepted: 12/03/2020] [Indexed: 11/16/2022] Open
Abstract
The control of dipteran pests is highly relevant to humans due to their involvement in the transmission of serious diseases including malaria, dengue fever, Chikungunya, yellow fever, zika, and filariasis; as well as their agronomic impact on numerous crops. Many bacteria are able to produce proteins that are active against insect species. These bacteria include Bacillus thuringiensis, the most widely-studied pesticidal bacterium, which synthesizes proteins that accumulate in crystals with insecticidal properties and which has been widely used in the biological control of insects from different orders, including Lepidoptera, Coleoptera, and Diptera. In this review, we summarize all the bacterial proteins, from B. thuringiensis and other entomopathogenic bacteria, which have described insecticidal activity against dipteran pests, including species of medical and agronomic importance.
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Kang S, Odom OW, Malone CL, Thangamani S, Herrin DL. Expression of a Synthetic Gene for the Major Cytotoxin (Cyt1Aa) of Bacillus thuringiensis subsp. israelensis in the Chloroplast of Wild-Type Chlamydomonas. BIOLOGY 2018; 7:biology7020029. [PMID: 29738473 PMCID: PMC6022862 DOI: 10.3390/biology7020029] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 04/30/2018] [Accepted: 05/04/2018] [Indexed: 12/16/2022]
Abstract
Chlamydomonas reinhardtii (Chlamydomonas) strains that are toxic to mosquito larvae because they express chloroplast transgenes that are based on the mosquitocidal proteins of Bacillus thuringiensis subsp. israelensis (Bti) could be very useful in mosquito control. Chlamydomonas has several advantages for this approach, including genetic controls not generally available with industrial algae. The Bti toxin is produced by sporulating bacteria and has been used for mosquito control for >30 years without creating highly resistant mosquito populations. The suite of toxins is four main proteins: three Cry proteins and the cytotoxic Cyt1Aa (27 kDa). Cyt1Aa is not very toxic to mosquitoes by itself, but it prevents the development of resistance. The production of Cyt1Aa in other microbes, however, has been challenging due to its affinity for certain membrane phospholipids. Here we report on the production of recombinant Cyt1Aa (rCyt1A) in the chloroplast of photosynthetic Chlamydomonas at levels of at least 0.3% total protein. Live cell bioassays demonstrated toxicity of the rCyt1Aa Chlamydomonas to larvae of Aedes aegypti. We also expressed the chloroplast cyt1Aa gene in a wild-type Chlamydomonas strain (21 gr) that can grow on nitrate. These results have implications for developing a Chlamydomonas strain that will be toxic to mosquito larvae but will not induce strongly resistant populations.
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Affiliation(s)
| | - Obed W Odom
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA.
| | - Candice L Malone
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA.
| | - Saravanan Thangamani
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - David L Herrin
- Pond Life Technologies LLC, Cedar Park, TX 78613, USA.
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA.
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3
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Kang S, Odom OW, Thangamani S, Herrin DL. Toward mosquito control with a green alga: Expression of Cry toxins of Bacillus thuringiensis subsp. israelensis (Bti) in the chloroplast of Chlamydomonas. JOURNAL OF APPLIED PHYCOLOGY 2017; 29:1377-1389. [PMID: 28713202 PMCID: PMC5509220 DOI: 10.1007/s10811-016-1008-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We are developing Chlamydomonas strains that can be used for safe and sustainable control of mosquitoes, because they produce proteins from Bacillus thuringiensis subsp. israelensis (Bti) in the chloroplast. Chlamydomonas has a number of advantages for this approach, including genetic controls that are not generally available with industrial algae. The Bti toxin has been used for mosquito control for > 30 years and does not engender resistance; it contains three Cry proteins, Cry4Aa (135 kDa), Cry4Ba (128 kDa) and Cry11Aa (72 kDa), and Cyt1Aa (25 kDa). To express the Cry proteins in the chloroplast, the three genes were resynthesized and cry4Aa was truncated to the first 700 amino acids (cry4Aa700 ); also, since they can be toxic to host cells, the inducible Cyc6:Nac2-psbD expression system was used. Western blots of total protein from the chloroplast transformants showed accumulation of the intact polypeptides, and the relative expression level was Cry11Aa > Cry4Aa700 > Cry4Ba. Quantitative western blots with purified Cry11Aa as a standard showed that Cry11Aa accumulated to 0.35% of total cell protein. Live cell bioassays in dH20 demonstrated toxicity of the cry4Aa700 and cry11Aa transformants to larvae of Aedes aegypti and Culex quinquefasciatus. These results demonstrate that the Cry proteins that are most toxic to Aedes and Culex mosquitoes, Cry4Aa and Cry11Aa, can be successfully expressed in the chloroplast of Chlamydomonas.
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Affiliation(s)
- Seongjoon Kang
- Dept. of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
- Pond Life Technologies LLC, Cedar Park, TX 78613, USA
| | - Obed W. Odom
- Dept. of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Saravanan Thangamani
- Dept. of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - David L. Herrin
- Dept. of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
- Pond Life Technologies LLC, Cedar Park, TX 78613, USA
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4
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Al-Haj L, Lui YT, Abed RMM, Gomaa MA, Purton S. Cyanobacteria as Chassis for Industrial Biotechnology: Progress and Prospects. Life (Basel) 2016; 6:life6040042. [PMID: 27916886 PMCID: PMC5198077 DOI: 10.3390/life6040042] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 11/13/2016] [Accepted: 11/25/2016] [Indexed: 12/24/2022] Open
Abstract
Cyanobacteria hold significant potential as industrial biotechnology (IB) platforms for the production of a wide variety of bio-products ranging from biofuels such as hydrogen, alcohols and isoprenoids, to high-value bioactive and recombinant proteins. Underpinning this technology, are the recent advances in cyanobacterial “omics” research, the development of improved genetic engineering tools for key species, and the emerging field of cyanobacterial synthetic biology. These approaches enabled the development of elaborate metabolic engineering programs aimed at creating designer strains tailored for different IB applications. In this review, we provide an overview of the current status of the fields of cyanobacterial omics and genetic engineering with specific focus on the current molecular tools and technologies that have been developed in the past five years. The paper concludes by giving insights on future commercial applications of cyanobacteria and highlights the challenges that need to be addressed in order to make cyanobacterial industrial biotechnology more feasible in the near future.
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Affiliation(s)
- Lamya Al-Haj
- Biology Department, College of Science, Sultan Qaboos University, Al-Khoud, P.O. Box 36, Muscat 123, Oman.
| | - Yuen Tin Lui
- Institute of Structural & Molecular Biology, University College London, London WC1E 6BT, UK.
| | - Raeid M M Abed
- Biology Department, College of Science, Sultan Qaboos University, Al-Khoud, P.O. Box 36, Muscat 123, Oman.
| | - Mohamed A Gomaa
- Biology Department, College of Science, Sultan Qaboos University, Al-Khoud, P.O. Box 36, Muscat 123, Oman.
| | - Saul Purton
- Institute of Structural & Molecular Biology, University College London, London WC1E 6BT, UK.
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Uzair B, Tabassum S, Rasheed M, Rehman SF. Exploring marine cyanobacteria for lead compounds of pharmaceutical importance. ScientificWorldJournal 2012; 2012:179782. [PMID: 22545008 PMCID: PMC3324129 DOI: 10.1100/2012/179782] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 11/20/2011] [Indexed: 11/28/2022] Open
Abstract
The Ocean, which is called the "mother of origin of life," is also the source of structurally unique natural products that are mainly accumulated in living organisms. Cyanobacteria are photosynthetic prokaryotes used as food by humans. They are excellent source of vitamins and proteins vital for life. Several of these compounds show pharmacological activities and are helpful for the invention and discovery of bioactive compounds, primarily for deadly diseases like cancer, acquired immunodeficiency syndrome (AIDS), arthritis, and so forth, while other compounds have been developed as analgesics or to treat inflammation, and so forth. They produce a large variety of bioactive compounds, including substances with anticancer and antiviral activity, UV protectants, specific inhibitors of enzymes, and potent hepatotoxins and neurotoxins. Many cyanobacteria produce compounds with potent biological activities. This paper aims to showcase the structural diversity of marine cyanobacterial secondary metabolites with a comprehensive coverage of alkaloids and other applications of cyanobacteria.
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Affiliation(s)
- Bushra Uzair
- Department of Bioinformatics and Biotechnology, International Islamic University Islamabad, Sector H-10, 44000 Islamabad, Pakistan.
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7
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Koksharova OA. Application of molecular genetic and microbiological techniques in ecology and biotechnology of cyanobacteria. Microbiology (Reading) 2010. [DOI: 10.1134/s0026261710060020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Otieno-Ayayo ZN, Zaritsky A, Wirth MC, Manasherob R, Khasdan V, Cahan R, Ben-Dov E. Variations in the mosquito larvicidal activities of toxins from Bacillus thuringiensis ssp. israelensis. Environ Microbiol 2008; 10:2191-9. [PMID: 18637949 DOI: 10.1111/j.1462-2920.2008.01696.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Comparing activities of purified toxins from Bacillus thuringiensis ssp. israelensis against larvae of seven mosquito species (vectors of tropical diseases) that belong to three genera, gleaned from the literature, disclosed highly significant variations in the levels of LC(50) as well as in the hierarchy of susceptibilities. Similar toxicity comparisons were performed between nine transgenic Gram-negative species, four of which are cyanobacterial, expressing various combinations of cry genes, cyt1Aa and p20, against larvae of four mosquito species as potential agents for biological control. Reasons for inconsistencies are listed and discussed. Standard conditions for toxin isolation and presentation to larvae are sought. A set of lyophilized powders prepared identically from six Escherichia coli clones expressing combinations of four genes displayed toxicities against larvae of three mosquito species, with levels that differed between them but with identical hierarchy.
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Cyanobacterial toxins as allelochemicals with potential applications as algaecides, herbicides and insecticides. Mar Drugs 2008; 6:117-46. [PMID: 18728763 PMCID: PMC2525484 DOI: 10.3390/md20080007] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2008] [Revised: 05/01/2008] [Accepted: 05/12/2008] [Indexed: 11/16/2022] Open
Abstract
Cyanobacteria ("blue-green algae") from marine and freshwater habitats are known to produce a diverse array of toxic or otherwise bioactive metabolites. However, the functional role of the vast majority of these compounds, particularly in terms of the physiology and ecology of the cyanobacteria that produce them, remains largely unknown. A limited number of studies have suggested that some of the compounds may have ecological roles as allelochemicals, specifically including compounds that may inhibit competing sympatric macrophytes, algae and microbes. These allelochemicals may also play a role in defense against potential predators and grazers, particularly aquatic invertebrates and their larvae. This review will discuss the existing evidence for the allelochemical roles of cyanobacterial toxins, as well as the potential for development and application of these compounds as algaecides, herbicides and insecticides, and specifically present relevant results from investigations into toxins of cyanobacteria from the Florida Everglades and associated waterways.
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10
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Cyanobacterial Toxins as Allelochemicals with Potential Applications as Algaecides, Herbicides and Insecticides. Mar Drugs 2008. [DOI: 10.3390/md6020117] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Zheng D, Valdez-Cruz NA, Armengol G, Sevrez C, Munoz-Olaya JM, Yuan Z, Orduz S, Crickmore N. Co-Expression of the Mosquitocidal Toxins Cyt1Aa and Cry11Aa from Bacillus thuringiensis Subsp. israelensis in Asticcacaulis excentricus. Curr Microbiol 2007; 54:58-62. [PMID: 17160360 DOI: 10.1007/s00284-006-0352-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2006] [Accepted: 08/14/2006] [Indexed: 10/23/2022]
Abstract
The cyt1Aa gene from Bacillus thuringiensis subsp. israelensis (Bti), whose product synergizes other mosquitocidal toxins, and functions as a repressor of resistance developed by mosquitoes against Bacilli insecticides, was introduced into the aquatic Gram-negative bacterium Asticcacaulis excentricus alongside the cry11Aa gene. The genes were introduced as an operon, but although mRNA was detected for both genes, no Cyt1Aa toxin was detected. Both proteins were expressed using a construct in which a promoter was inserted upstream of each gene. Recombinant A. excentricus expressing both toxins was found to be approximately twice as toxic to third instar larvae of Culex quinquefasciatus as transformants expressing just Cry11Aa.
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Affiliation(s)
- Dasheng Zheng
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, PR China
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Khasdan V, Ben-Dov E, Manasherob R, Boussiba S, Zaritsky A. Mosquito larvicidal activity of transgenic Anabaena PCC 7120 expressing toxin genes from Bacillus thuringiensis subsp. israelensis. FEMS Microbiol Lett 2004; 227:189-95. [PMID: 14592708 DOI: 10.1016/s0378-1097(03)00679-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Genes encoding the mosquito larvicidal toxins Cry4Aa, Cry11Aa, Cyt1Aa and the regulatory P20 from Bacillus thuringiensis subsp. israelensis were introduced into the nitrogen-fixing, filamentous cyanobacterium Anabaena PCC 7120 for expression under control of two strong promoters P(psbA) and P(A1). The clone pRVE4-ADRC displayed toxicity against fourth-instar larvae of Aedes aegypti, the highest ever achieved in cyanobacteria. It was about 2.5-fold more toxic than the respective clone without cyt1Aa [Wu et al., Appl. Environ. Microbiol. 63 (1997) 4971-4975]. Cyt1Aa synergized the combination of Crys by about five-fold. Consistently, the lethal times exerted by pRVE4-ADRC were also reduced (it killed exposed larvae more quickly). This clone may become a useful biological control agent which reduces the probability of resistance development in the target organisms [Wirth et al., Proc. Natl. Acad. Sci. USA 94 (1997) 10536-10540].
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Affiliation(s)
- Vadim Khasdan
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, 84105, Be'er-Sheva, Israel
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Tanapongpipat S, Nantapong N, Cole J, Panyim S. Stable integration and expression of mosquito-larvicidal genes from Bacillus thuringiensis subsp. israelensis and Bacillus sphaericus into the chromosome of Enterobacter amnigenus: a potential breakthrough in mosquito biocontrol. FEMS Microbiol Lett 2003; 221:243-8. [PMID: 12725934 DOI: 10.1016/s0378-1097(03)00203-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Previously, we have successfully integrated a spectinomycin/streptomycin resistance gene into Enterobacter amnigenus strain An11, a potential host for mosquito control, using in vivo recombination via homologous recombination (An11S4::Omega). We now report the successful transfer of two mosquito-larvicidal genes, cry4B from Bacillus thuringiensis subsp. israelensis and binary toxin genes from Bacillus sphaericus, into the host genome. To facilitate the screening procedure, the E. amnigenus derivative, An11S4::Omega, was used as a host. The integration of both toxin genes by two successive crossover events interrupted the Omega region yielding two integrants designated An11S4::cry4B and An11S4::Omega::bin, respectively. Differences in the integration efficiency of these toxin genes were observed. The presence of both genes in the target sites of the host genome was verified by PCR. Cry4B was expressed weakly from An11S4::cry4B, but no expression of the binary toxin gene could be detected from An11S4::Omega::bin. Nevertheless, these two integrants exhibited mosquito-larvicidal activity against Aedes and Culex, suggesting that both proteins were expressed, but at very low levels.
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Affiliation(s)
- Sutipa Tanapongpipat
- Biotec Central Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Phaholyothin Road, Klong 1, Klong Luang, Pathumthani, Thailand.
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14
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Chungjatupornchai W, Fa-aroonsawat S, Panyim S. Characterization of regions of the cyanobacterial tRNA(pro) gene that affect the expression of a beta-glucuronidase reporter gene. FEMS Microbiol Lett 2002; 211:57-64. [PMID: 12052551 DOI: 10.1111/j.1574-6968.2002.tb11203.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The E3 strong promoter-active fragment harbors the tRNA(pro) (GGG) gene upstream of the promoterless beta-glucuronidase (GUS) reporter gene in plasmid pKG-E3. The 74-bp tRNA(pro) coding sequence contains two regions exhibiting strong homology to blocks A and B which are the split promoter elements of eukaryotic tRNA genes. Results in this study showed that the promoter region of tRNA(pro) gene located upstream of its coding sequence and harbored the putative -10 (TACATT) and -35 (TTGGCA) regions which conformed to the Escherichia coli sigma(70) promoter. Differentiation of the 5' end of tRNA(pro)-GUS transcripts of pKG-E3 revealed that the true transcription initiation sites were located at positions -3, -4, and -6, while the processed sites were located at position +75, +76 and +78 with respect to the first nucleotide of the tRNA(pro) coding sequence. The presence of block A decreased GUS activity about three-fold, whereas block B and the 3' end of tRNA(pro) gene completely abolished GUS expression. However, the presence of full-length tRNA(pro) gene did not affect the GUS expression. Downstream of the tRNA(pro) coding sequence in chromosomal DNA contained a 32-bp stem-loop structure with a predicted DeltaG value of -21.7 kcal x mol(-1). The absence of this stem-loop structure downstream of the tRNA(pro) coding sequence in pKG-E3 resulted in read-through transcription into the adjoining GUS gene.
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MESH Headings
- Base Sequence
- Cyanobacteria/genetics
- Gene Expression Regulation, Bacterial
- Genes, Bacterial/genetics
- Genes, Reporter/genetics
- Glucuronidase/genetics
- Promoter Regions, Genetic/genetics
- RNA, Bacterial/chemistry
- RNA, Bacterial/genetics
- RNA, Bacterial/metabolism
- RNA, Messenger/chemistry
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Transfer, Pro/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Transcription Initiation Site
- Transcription, Genetic/genetics
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Affiliation(s)
- Wipa Chungjatupornchai
- Institute of Molecular Biology and Genetics, Mahidol University, Salaya Campus, 73170, Nakornpathom, Thailand.
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Nantapong N, Tanapongpipat S, Cole J, Panyim S. Development of a method for heterologous gene expression in Enterobacter amnigenus, a potential host for the biological control of mosquito larvi. J Microbiol Methods 2002; 49:329-34. [PMID: 11869800 DOI: 10.1016/s0167-7012(01)00384-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
An integrative plasmid containing a 1.3 kb fragment of chromosomal DNA from Enterobacter amnigenus was constructed. The Omega fragment encoding spectinomycin/streptomycin resistance was cloned into the unique BglII site of the resulting plasmid, and the interrupted fragment was transferred via plasmid pMAK705 by electroporation into E. amnigenus with a selection for spectinomycin resistance. Cointegrants were resolved to generate an E. amnigenus strain that expressed spectinomycin resistance, but grew as rapidly as the parental strain. The cloned fragment encodes a putative homologue of the proW gene of Escherichia coli that is not essential for E. amnigenus growth. The integrative plasmid is now available to introduce any heterologous DNA into the E. amnigenus chromosome, for the construction of promoter-probe vectors for the studies of gene regulation, or to construct plasmids suitable for the isolation of secretion signals. Immediate applications of this system will include the expression and secretion of crystal toxins from bacilli for the biological control of mosquito larvae infected with the bacterial host.
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Affiliation(s)
- Nawarat Nantapong
- Institute of Molecular Biology and Genetics, Mahidol University, Salaya Campus, Nakornpathom, 73170 Thailand
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Romero M, Gil FM, Orduz S. Expression of mosquito active toxin genes by a Colombian native strain of the gram-negative bacterium Asticcacaulis excentricus. Mem Inst Oswaldo Cruz 2001; 96:257-63. [PMID: 11285507 DOI: 10.1590/s0074-02762001000200021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mosquito control with biological insecticides, such as Bacillus sp. toxins, has been used widely in many countries. However, rapid sedimentation away from the mosquito larvae feeding zone causes a low residual effect. In order to overcome this problem, it has been proposed to clone the Bacillus toxin genes in aquatic bacteria which are able to live in the upper part of the water column. Two strains of Asticcacaulis excentricus were chosen to introduce the B. sphaericus binary toxin gene and B. thuringiensis subsp. medellin cry11Bb gene cloned in suitable vectors. In feeding experiments with these aquatic bacteria, it was shown that Culex quinquefasciatus, Aedes aegypti, and Anopheles albimanus larvae were able to survive on a diet based on this wild bacterium. A. excentricus recombinant strains were able to express both genes, but the recombinant strain expressing the B. sphaericus binary toxin was toxic to mosquito larvae. Crude protease A. excentricus extracts did not degrade the Cry11Bb toxin. The flotability studies indicated that the recombinant A. excentricus strains remained in the upper part of the water column longer than the wild type Bacillus strains.
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Affiliation(s)
- M Romero
- Unidad de Biotecnología y Control Biológico, Corporación para Investigaciones Biológicas, Medellín, Colombia
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Xiaoqiang W, Vennison SJ, Huirong L, Ben-Dov E, Zaritsky A, Boussiba S. Mosquito larvicidal activity of transgenic Anabaena strain PCC 7120 expressing combinations of genes from Bacillus thuringiensis subsp. israelensis. Appl Environ Microbiol 1997; 63:4971-4. [PMID: 9406420 PMCID: PMC168827 DOI: 10.1128/aem.63.12.4971-4974.1997] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Various combinations of the genes cryIVA (cry4A), cryIVD (cry11A), and p20 from Bacillus thuringiensis subsp. israelensis were introduced into the nitrogen-fixing cyanobacterium Anabaena sp. strain PCC 7120 by means of Escherichia coli-Anabaena shuttle vector pRL488p and were expressed under control of two tandem strong promoters, a cyanobacterial promoter (PpsbA) and an E. coli T7 promoter (PA1). Two of the clones carrying cryIVA plus cryIVD, one with p20 and one without p20, displayed toxicity against third-instar larvae of Aedes aegypti at levels greater than any level previously reported for transgenic cyanobacteria.
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Affiliation(s)
- W Xiaoqiang
- Blaustein Institute for Desert Research, Ben-Gurion University at Sede-Boker, Israel
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18
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Evaluation of four fresh-water unicellular cyanobacteria as potential hosts for mosquitocidal toxins. Biotechnol Lett 1996. [DOI: 10.1007/bf00128675] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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19
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Kumar PA, Sharma RP, Malik VS. The insecticidal proteins of Bacillus thuringiensis. ADVANCES IN APPLIED MICROBIOLOGY 1996; 42:1-43. [PMID: 8865583 DOI: 10.1016/s0065-2164(08)70371-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- P A Kumar
- National Research Centre for Plant Biotechnology, Indian Agricultural Research Institute, New Delhi, India
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20
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Charles JF, Nielsen-LeRoux C. Les bactéries entomopathogènes: mode d'action sur les larves de moustiques et phénomènes de résistance. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s0924-4204(97)86392-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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21
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Soltes-Rak E, Kushner DJ, Williams DD, Coleman JR. Factors regulating cryIVB expression in the cyanobacterium--Synechococcus PCC 7942. MOLECULAR & GENERAL GENETICS : MGG 1995; 246:301-8. [PMID: 7531814 DOI: 10.1007/bf00288602] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The expression of the larvicidal Bacillus thuringiensis subsp. israelensis cryIVB gene in cyanobacteria has been suggested to be an effective means of controlling mosquito populations. Using a variety of cryIVB constructs, in this study we have examined the effect of Synechococcus PCC 7942 culture age on intracellular toxin levels and have attempted to determine the mechanisms by which cryIVB gene expression is regulated. The data suggest that specific degradation of the cryIVB mRNA limits toxin production; however, the addition of cyanobacterial 3' untranslated DNA sequences to the cryIVB gene did not improve mRNA stability or toxin levels. An analysis of the cryIVB sequence and comparison of codon usage patterns with highly expressed cyanobacterial genes suggest that inefficient translation and intragenic ribosomal binding sites impede protein synthesis and result in rapid turnover of the toxin mRNA.
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MESH Headings
- Bacillus thuringiensis/chemistry
- Bacillus thuringiensis/genetics
- Bacillus thuringiensis Toxins
- Bacterial Proteins/biosynthesis
- Bacterial Proteins/genetics
- Bacterial Toxins
- Base Sequence
- Codon/genetics
- Cyanobacteria/genetics
- Cyanobacteria/growth & development
- Cyanobacteria/metabolism
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- Endotoxins/biosynthesis
- Endotoxins/genetics
- Gene Expression Regulation, Bacterial
- Genes, Bacterial/genetics
- Hemolysin Proteins
- Molecular Sequence Data
- Nucleic Acid Conformation
- Promoter Regions, Genetic/genetics
- RNA Processing, Post-Transcriptional
- RNA, Bacterial/biosynthesis
- RNA, Bacterial/metabolism
- RNA, Messenger/biosynthesis
- RNA, Messenger/metabolism
- Recombinant Fusion Proteins/biosynthesis
- Ribosomes/metabolism
- Transcription, Genetic
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Affiliation(s)
- E Soltes-Rak
- Dept. of Botany, University of Toronto, Ontario, Canada
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22
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Yap WH, Thanabalu T, Porter AG. Expression of mosquitocidal toxin genes in a gas-vacuolated strain of Ancylobacter aquaticus. Appl Environ Microbiol 1994; 60:4199-202. [PMID: 7993101 PMCID: PMC201962 DOI: 10.1128/aem.60.11.4199-4202.1994] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
A series of plasmids bearing the binary toxin genes of Bacillus sphaericus 2297 or 2317.3, the 100-kDa toxin gene of B. sphaericus SSII-1, or the 130-kDa (cryIVB) toxin gene of Bacillus thuringiensis subsp. israelensis were constructed and introduced into Ancylobacter aquaticus by electroporation. The transformed A. aquaticus cells exhibited significant toxicity towards mosquito larvae, demonstrating a potential use of recombinant A. aquaticus for biological control of mosquitoes.
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Affiliation(s)
- W H Yap
- Institute of Molecular and Cell Biology, National University of Singapore
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23
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Takeshima Y, Takatsugu N, Sugiura M, Hagiwara H. High-level expression of human superoxide dismutase in the cyanobacterium Anacystis nidulans 6301. Proc Natl Acad Sci U S A 1994; 91:9685-9. [PMID: 7937873 PMCID: PMC44881 DOI: 10.1073/pnas.91.21.9685] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
A chemically synthesized gene encoding human CuZn superoxide dismutase (hSOD) was cloned into the shuttle vector pBAX18R and expressed in Anacystis nidulans 6301 (Synechococcus sp. strain PCC 6301) under the control of a ribulose-1,5-bisphosphate carboxylase/oxygenase gene (rbc) promoter derived from A. nidulans 6301. The sequences immediately upstream from the hSOD coding region and the distances between the ribosomal binding site and ATG initiation codon strongly affected the expression of the hSOD gene in A. nidulans cells. Optimal expression of hSOD was obtained with the expression vector pBAXSOD8-I, which contained a GGAGAG sequence. In defined conditions, irradiation with light increased hSOD enzyme activity in the transformants > 18-fold and the level of the hSOD protein reached a value of about 3% of the total soluble protein. The transformants that expressed hSOD acquired the ability to extenuate photooxidative damage induced by methyl viologen.
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24
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25
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Bora RS, Murty MG, Shenbagarathai R, Sekar V. Introduction of a Lepidopteran-Specific Insecticidal Crystal Protein Gene of
Bacillus thuringiensis
subsp.
kurstaki
by Conjugal Transfer into a
Bacillus megaterium
Strain That Persists in the Cotton Phyllosphere. Appl Environ Microbiol 1994; 60:214-22. [PMID: 16349152 PMCID: PMC201291 DOI: 10.1128/aem.60.1.214-222.1994] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A lepidopteran toxin gene of the entomopathogen
Bacillus thuringiensis
subsp.
kurstaki
HD-1 was introduced into a cotton leaf-colonizing
Bacillus megaterium
strain, RS1, by conjugal transfer. Rifampin- and nalidixic acid-resistant colonies obtained after cell mating were screened for crystal production by microscopy. A transcipient,
B. megaterium
RS1-43, was selected by this procedure. Southern blot hybridization with both total DNA and
Hind
III-digested DNA of the transcipient showed positive signals with a
cryIA
-specific probe, suggesting the transfer of the lepidopteran-specific
cryIA(a)
gene. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblot analysis confirmed the presence of the 134-kDa toxic crystal protein specific to lepidopteran larvae in the transcipient. Survival studies with cultures of the transcipient at both vegetative and postvegetative growth stages on cotton, under field conditions, suggested that the bacterium persisted on the leaf surfaces for more than 28 days, with a gradual decline in the population level with time, while the donor,
B. thuringiensis
subsp.
kurstaki
, disappeared completely after 7 days following inoculation. An in situ differential crystal-staining technique indicated the production of crystals by the transcipient on cotton leaf surfaces for about 30 days. Leaf bioassays of cotton plants inoculated with a single spray of the transcipient showed 75- to 96% mortality to the first-instar larvae of
Heliothis armigera
up to 21 days, and this single spray conferred total protection to the plants for about 30 days by causing an antifeeding effect on the remaining larvae.
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Affiliation(s)
- R S Bora
- Department of Biotechnology, Madurai Kamaraj University, Madurai 625 021, India
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26
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Porter AG, Davidson EW, Liu JW. Mosquitocidal toxins of bacilli and their genetic manipulation for effective biological control of mosquitoes. Microbiol Rev 1993; 57:838-61. [PMID: 7905597 PMCID: PMC372941 DOI: 10.1128/mr.57.4.838-861.1993] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The identification, cloning, and characterization of protein toxins from various species of bacilli have demonstrated the existence of mosquitocidal toxins with different structures, mechanisms of action, and host ranges. A start has been made in understanding the polypeptide determinants of toxicity and insecticidal activity, and the purification of toxins from recombinant organisms may lead to the elucidation of their X-ray crystal structures and the cloning of brush border membrane receptors. The results of cloning mosquitocidal toxins in heterologous microorganisms show the potential of expanding the range of susceptible mosquito species by combining several toxins of different host specificity in one cell. Toxins have been expressed in new microorganisms with the potential for increasing potency by persisting at the larval feeding zone. The powerful tools of bacterial genetics are being applied to engineer genetically stable, persistent toxin expression and expand the insecticidal host ranges of Bacillus sphaericus and Bacillus thuringiensis strains. These techniques, together with modern formulation technology, should eventually lead to the construction of mosquitocidal microorganisms which are effective enough to have a real impact on mosquito-borne diseases.
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Affiliation(s)
- A G Porter
- Institute of Molecular and Cell Biology, National University of Singapore
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27
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Soltes-Rak E, Kushner DJ, Williams DD, Coleman JR. Effect of promoter modification on mosquitocidal cryIVB gene expression in Synechococcus sp. strain PCC 7942. Appl Environ Microbiol 1993; 59:2404-10. [PMID: 7690220 PMCID: PMC182298 DOI: 10.1128/aem.59.8.2404-2410.1993] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The impact of promoter modification on the expression of the mosquitocidal Bacillus thuringiensis subsp. israelensis cryIVB gene when used to transform the cyanobacterium Synechococcus sp. strain PCC 7942 has been examined. Maximal transcript and protein abundances were achieved by the addition of the lacZ promoter upstream of the cryIVB sequence. Replacement of the endogenous corresponding Bacillus sequences with the Synechococcus petF1 promoter, ribosome binding site, and initiation codon also resulted in increased expression of the cryIVB gene relative to the expression obtained with the Bacillus promoter alone but decreased expression relative to the expression achieved with the tandem array of the Bacillus and lacZ promoters. Synechococcus cells carrying plasmids in which the expression of the cryIVB gene was regulated by either the lacZ or the petF1 promoter were readily consumed by first-instar Culex restuans larvae and proved to be toxic for these organisms.
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Affiliation(s)
- E Soltes-Rak
- Department of Botany, University of Toronto, Ontario, Canada
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28
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Bhattacharya M, Plantz BA, Swanson-Kobler JD, Nickerson KW. Nonenzymatic Glycosylation of Lepidopteran-Active
Bacillus thuringiensis
Protein Crystals. Appl Environ Microbiol 1993; 59:2666-72. [PMID: 16349021 PMCID: PMC182336 DOI: 10.1128/aem.59.8.2666-2672.1993] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We used high-pH anion-exchange chromatography with pulsed amperometric detection to quantify the monosaccharides covalently attached to
Bacillus thuringiensis
HD-1 (Dipel) crystals. The crystals contained 0.54% sugars, including, in decreasing order of prevalence, glucose, fucose, arabinose/rhamnose, galactose, galactosamine, glucosamine, xylose, and mannose. Three lines of evidence indicated that these sugars arose from nonenzymatic glycosylation: (i) the sugars could not be removed by
N
- or
O
-glycanases; (ii) the sugars attached were influenced both by the medium in which the bacteria had been grown and by the time at which the crystals were harvested; and (iii) the chemical identity and stoichiometry of the sugars detected did not fit any known glycoprotein models. Thus, the sugars detected were the product of fermentation conditions rather than bacterial genetics. The implications of these findings are discussed in terms of crystal chemistry, fermentation technology, and the efficacy of
B. thuringiensis
as a microbial insecticide.
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Affiliation(s)
- M Bhattacharya
- School of Biological Sciences, University of Nebraska, Lincoln, Nebraska 68588-0343
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29
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Xudong X, Renqiu K, Yuxiang H. High larvicidal activity of intact recombinant cyanobacteriumAnabaenasp. PCC 7120 expressing Gene 51 and Gene 42 ofBacillus sphaericussp. 2297. FEMS Microbiol Lett 1993. [DOI: 10.1111/j.1574-6968.1993.tb06037.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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30
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Murphy RC, Stevens SE. Cloning and expression of the cryIVD gene of Bacillus thuringiensis subsp. israelensis in the cyanobacterium Agmenellum quadruplicatum PR-6 and its resulting larvicidal activity. Appl Environ Microbiol 1992; 58:1650-5. [PMID: 1622235 PMCID: PMC195653 DOI: 10.1128/aem.58.5.1650-1655.1992] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
A mosquitocidal cyanobacterium has been developed by introducing the mosquito-toxic cryIVD gene from Bacillus thuringiensis subsp. israelensis into the unicellular cyanobacterium Agmenellum quadruplicatum PR-6 (Synechococcus sp. strain PCC 7002). The cryIVD gene was introduced into the cyanobacterium on a derivative of the PR-6 expression vector pAQE19 delta Sal in which the cryIVD gene was translationally fused to the initial coding sequence of the highly expressed PR-6 cpcB gene. Coomassie blue staining and immunoblot analysis of gel-fractionated cell extract polypeptides indicate that the cpcB-cryIVD gene fusion is expressed at high levels in the cyanobacterial cells, with little or no apparent degradation of the cryIVD gene product. Larvicidal assays revealed that freshly hatched Culex pipiens mosquito larvae readily ingested the transformed cyanobacteria and that the cells proved to be toxic to the larvae.
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Affiliation(s)
- R C Murphy
- Department of Biology, Memphis State University, Memphis, Tennessee 38152
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31
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Khawaled K, Cohen T, Zaritsky A. Digestion of Bacillus thuringiensis var. israelensis spores by larvae of Aedes aegypti. J Invertebr Pathol 1992; 59:186-9. [PMID: 1607667 DOI: 10.1016/0022-2011(92)90031-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The larvicidal activity of Bacillus thuringiensis var. israelensis against mosquitoes and the blackfly is included in parasporal crystalline bodies which are produced during sporulation. Following ingestion, the crystals are solubilized in the larval midgut and induce death within a short time; the spores germinate in the dead larvae and complete a growth cycle. The fate of the spores in surviving live larvae was elucidated by using a nonlarvicidal B. thuringiensis var. israelensis mutant. When introduced as the only food source, spores of this mutant support development to the adult stage of newly hatched Aedes aegypti larvae at a rate directly related to spore concentration. The conclusion that spores of B. thuringiensis var. israelensis are digested in the larval gut was substantiated by following the incorporation of [35S]methionine-labeled spores into larval tissues.
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Affiliation(s)
- K Khawaled
- Department of Life Sciences, Ben-Gurion University of the Negev, Be'er-Sheva, Israel
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32
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Thanabalu T, Hindley J, Brenner S, Oei C, Berry C. Expression of the mosquitocidal toxins of Bacillus sphaericus and Bacillus thuringiensis subsp. israelensis by recombinant Caulobacter crescentus, a vehicle for biological control of aquatic insect larvae. Appl Environ Microbiol 1992; 58:905-10. [PMID: 1575492 PMCID: PMC195353 DOI: 10.1128/aem.58.3.905-910.1992] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
In the quest for effective control of mosquitoes, attention has turned increasingly to strains of the bacteria Bacillus sphaericus and Bacillus thuringiensis subsp. israelensis, which produce potent toxins with specific mosquitocidal activities. However, sedimentation of the bacterial spores limits the duration of effective control after field application of these bacilli. We describe here the cloning of genes encoding the 51.4- and 41.9-kDa toxins from B. sphaericus 2297, the 100-kDa toxin from B. sphaericus SSII-1, and the 130-kDa toxin from B. thuringiensis subsp. israelensis into the broad-host-range plasmid pRK248 and the transfer of these genes for expression in Caulobacter crescentus CB15. The recombinant C. crescentus cells were shown to be toxic to mosquito larvae. Caulobacter species are ubiquitous microorganisms residing in the upper regions of aquatic environments and therefore provide the potential for prolonged control by maintaining mosquitocidal toxins in larval feeding zones.
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Affiliation(s)
- T Thanabalu
- Institute of Molecular and Cell Biology, National University of Singapore
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33
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Kawata Y, Yamano N, Kojima H, Itoh S. Expression of salmon growth hormone in the cyanobacteriumAgmenellum quadruplicatum. Biotechnol Lett 1991. [DOI: 10.1007/bf01022085] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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34
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Thiery I, Nicolas L, Rippka R, Tandeau de Marsac N. Selection of cyanobacteria isolated from mosquito breeding sites as a potential food source for mosquito larvae. Appl Environ Microbiol 1991; 57:1354-9. [PMID: 1677241 PMCID: PMC182954 DOI: 10.1128/aem.57.5.1354-1359.1991] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
One way to increase the persistence of larvicidal toxins in mosquito breeding sites is to clone the corresponding genes in microorganisms, such as cyanobacteria, which could serve as a source of food for the larvae. We isolated and cultured 10 strains of cyanobacteria from three mosquito breeding sites along the French Mediterranean coast. Most of the strains were tolerant to a relatively wide range of salt concentrations, and all of them were totally or partially resistant to at least four of the five biological or chemical larvicides used in the local mosquito control program. Six unicellular strains from these habitats and Synechococcus strain PCC 7942, a strain maintained for more than 10 years under laboratory conditions, were assessed for ingestion and digestion by larvae Culex pipiens and Anopheles gambiae mosquitoes. The numbers of cells ingested and digested were dependent on the cyanobacterial strain and varied with the mosquito species. Three of the new isolates, Synechococcus strain PCC 8905 and Synechocystis strains PCC 8906 and PCC 8912, were ingested and digested rapidly by larvae of both mosquito species. Since these strains are also tolerant to larvicides and relatively resistant to elevated salt concentrations, they meet the basic requirements for potential recipients of bacterial genes that encode endotoxins.
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Affiliation(s)
- I Thiery
- Unité des Bactéries Entomopathogènes, Institut Pasteur, Paris, France
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35
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Gawron-Burke C, Baum JA. Genetic Manipulation of Bacillus Thuringiensis Insecticidal Crystal Protein Genes in Bacteria. GENETIC ENGINEERING 1991; 13:237-63. [PMID: 1367416 DOI: 10.1007/978-1-4615-3760-1_11] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
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36
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Expression of the mosquitocidal-protein genes ofBacillus thuringiensis subsp.israelensis and the herbicide-resistance genebar inSynechocystis PCC6803. Curr Microbiol 1990. [DOI: 10.1007/bf02092092] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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