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Johnson TJ, Gibbons JL, Gu L, Zhou R, Gibbons WR. Molecular genetic improvements of cyanobacteria to enhance the industrial potential of the microbe: A review. Biotechnol Prog 2016; 32:1357-1371. [DOI: 10.1002/btpr.2358] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 08/30/2016] [Indexed: 12/17/2022]
Affiliation(s)
- Tylor J. Johnson
- Dept. of Biology and MicrobiologySouth Dakota State UniversityBrookings SD57007
- Dept. of MicrobiologyThe University of TennesseeKnoxville TN37996
| | - Jaimie L. Gibbons
- Dept. of Biology and MicrobiologySouth Dakota State UniversityBrookings SD57007
| | - Liping Gu
- Dept. of Biology and MicrobiologySouth Dakota State UniversityBrookings SD57007
| | - Ruanbao Zhou
- Dept. of Biology and MicrobiologySouth Dakota State UniversityBrookings SD57007
| | - William R. Gibbons
- Dept. of Biology and MicrobiologySouth Dakota State UniversityBrookings SD57007
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2
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Palma L, Muñoz D, Berry C, Murillo J, Caballero P. Bacillus thuringiensis toxins: an overview of their biocidal activity. Toxins (Basel) 2014; 6:3296-325. [PMID: 25514092 PMCID: PMC4280536 DOI: 10.3390/toxins6123296] [Citation(s) in RCA: 349] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 11/07/2014] [Accepted: 12/03/2014] [Indexed: 11/16/2022] Open
Abstract
Bacillus thuringiensis (Bt) is a Gram positive, spore-forming bacterium that synthesizes parasporal crystalline inclusions containing Cry and Cyt proteins, some of which are toxic against a wide range of insect orders, nematodes and human-cancer cells. These toxins have been successfully used as bioinsecticides against caterpillars, beetles, and flies, including mosquitoes and blackflies. Bt also synthesizes insecticidal proteins during the vegetative growth phase, which are subsequently secreted into the growth medium. These proteins are commonly known as vegetative insecticidal proteins (Vips) and hold insecticidal activity against lepidopteran, coleopteran and some homopteran pests. A less well characterized secretory protein with no amino acid similarity to Vip proteins has shown insecticidal activity against coleopteran pests and is termed Sip (secreted insecticidal protein). Bin-like and ETX_MTX2-family proteins (Pfam PF03318), which share amino acid similarities with mosquitocidal binary (Bin) and Mtx2 toxins, respectively, from Lysinibacillus sphaericus, are also produced by some Bt strains. In addition, vast numbers of Bt isolates naturally present in the soil and the phylloplane also synthesize crystal proteins whose biological activity is still unknown. In this review, we provide an updated overview of the known active Bt toxins to date and discuss their activities.
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Affiliation(s)
- Leopoldo Palma
- Instituto de Agrobiotecnología, CSIC-UPNA-Gobierno de Navarra, Campus Arrosadía, Mutilva Baja, 31192 Navarra, Spain.
| | - Delia Muñoz
- Grupo de Protección Cultivos, Departamento de Producción Agraria, Escuela Técnica Superior de Ingenieros Agrónomos, Universidad Pública de Navarra, Pamplona, 31006 Navarra, Spain.
| | - Colin Berry
- Cardiff School of Biosciences, Cardiff University, Park Place, Cardiff CF10 3AT, UK.
| | - Jesús Murillo
- Grupo de Protección Cultivos, Departamento de Producción Agraria, Escuela Técnica Superior de Ingenieros Agrónomos, Universidad Pública de Navarra, Pamplona, 31006 Navarra, Spain.
| | - Primitivo Caballero
- Instituto de Agrobiotecnología, CSIC-UPNA-Gobierno de Navarra, Campus Arrosadía, Mutilva Baja, 31192 Navarra, Spain.
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3
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Chungjatupornchai W, Fa-Aroonsawat S. The rrnA promoter as a tool for the improved expression of heterologous genes in cyanobacteria. Microbiol Res 2013; 169:361-8. [PMID: 24140155 DOI: 10.1016/j.micres.2013.09.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 08/02/2013] [Accepted: 09/15/2013] [Indexed: 11/28/2022]
Abstract
The regulatory sequence of ribosomal RNA A (rrnA) operon from Synechococcus PCC7942 was characterized using green fluorescent protein gene (gfp) as a reporter. The PR promoter (nt. -83 to +2) including upstream promoter element and P1 promoter of rrnA exhibited GFP fluorescence intensity about 30-fold higher than full length sequence (nt. -147 to +79). The effects of PR promoter arranged in tandem with consensus-σ(70) promoter (PS) of Escherichia coli on the expression of gfp and opd gene encoding organophosphorus hydrolase (OPH) in Synechococcus were investigated. The PS-PR tandem promoter was superior to all of the other promoters; its GFP fluorescence intensity was a 1.8-fold increase when compared to PR-PR tandem promoter, a 2.5-fold, 9.5-fold and a 15-fold increase compared to PR, PS and promoter of tRNA(pro), respectively. The GFP from PS-PR tandem promoter accounted for about 12% of its total extracted proteins. OPH activity of Synechococcus harboring opd gene under the control of PS-PR tandem promoter was 738 ± 128 units/OD₇₃₀. We demonstrated that the tandem promoters remarkably enhanced the GFP and OPH production which were detected on SDS-PAGE stained with Coomassie blue. The promoter system in this study could be generally applied to production of valuable organic products from cyanobacteria.
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Affiliation(s)
- Wipa Chungjatupornchai
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakornpathom 73170, Thailand.
| | - Sirirat Fa-Aroonsawat
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakornpathom 73170, Thailand
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4
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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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5
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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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6
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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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7
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Pulz O, Gross W. Valuable products from biotechnology of microalgae. Appl Microbiol Biotechnol 2004; 65:635-48. [PMID: 15300417 DOI: 10.1007/s00253-004-1647-x] [Citation(s) in RCA: 802] [Impact Index Per Article: 40.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2004] [Revised: 04/27/2004] [Accepted: 04/30/2004] [Indexed: 10/26/2022]
Abstract
The biotechnology of microalgae has gained considerable importance in recent decades. Applications range from simple biomass production for food and feed to valuable products for ecological applications. For most of these applications, the market is still developing and the biotechnological use of microalgae will extend into new areas. Considering the enormous biodiversity of microalgae and recent developments in genetic engineering, this group of organisms represents one of the most promising sources for new products and applications. With the development of sophisticated culture and screening techniques, microalgal biotechnology can already meet the high demands of both the food and pharmaceutical industries.
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Affiliation(s)
- Otto Pulz
- IGV Institut für Getreideverarbeitung GmbH, Arthur-Scheunert-Allee 40-41, 14558 Nuthetal, Germany.
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8
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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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10
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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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11
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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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12
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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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Sakai M, Ogawa T, Matsuoka M, Fukuda H. Photosynthetic conversion of carbon dioxide to ethylene by the recombinant cyanobacterium, Synechococcus sp. PCC 7942, which harbors a gene for the ethylene-forming enzyme of Pseudomonas syringae. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0922-338x(97)82004-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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14
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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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15
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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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16
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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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17
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Delécluse A, Barloy F, Rosso ML. Les bactéries pathogènes des larves de diptères: structure et spécificité des toxines. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s0924-4204(97)86391-3] [Citation(s) in RCA: 5] [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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18
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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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Abstract
The strengths of several promoters were assessed in the cyanobacterium Anabaena PCC 7120 by fusing them to luxAB, encoding bacterial luciferase. Two promoters, Ptac and PpsbA, with sequences nearly identical to consensus Escherichia coli sigma 70 promoters, gave as high or higher expression than the strong Anabaena promoter, Prbc. Pnpt, the natural promoter driving expression of the kanamycin-resistance determinant from Tn5, was poorly expressed in Anabaena. The Lac repressor partially repressed expression from Ptac, permitting regulated expression in Anabaena after induction with isopropyl thiogalactoside to a level 4-5-fold higher than without inducer.
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Affiliation(s)
- J Elhai
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing 48824
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20
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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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21
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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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