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. 1997 Dec;63(12):4664–4670. doi: 10.1128/aem.63.12.4664-4670.1997

Molecular cloning and characterization of a novel mosquitocidal protein gene from Bacillus thuringiensis subsp. fukuokaensis.

H K Lee 1, S S Gill 1
PMCID: PMC168788  PMID: 9406385

Abstract

A novel mosquitocidal protein gene, cry20Aa, was cloned from Bacillus thuringiensis subsp. fukuokaensis (H-3a: 3d: 3e). The gene product, Cry20Aa, was naturally truncated and had a molecular mass of 86,138 Da. The Cry20Aa protein possessed five conserved sequence blocks, as do most other insecticidal Cry toxins. However, an amino acid comparison of Cry20Aa with other mosquitocidal toxins, including Cry4A, Cry4B, Cry10A, Cry11A, and Cry11B, demonstrated that Cry20Aa was quite different from other toxins except for the conserved blocks. The N terminus of Cry20Aa was, however, homologous to the N termini of Cry4A and Cry10A. Interestingly, an inverted repeat (IR1) sequence in the open reading frame of the cry20Aa gene caused incomplete expression of Cry20Aa. When this internal IR1 sequence was altered with no change of amino acid sequence, acrystalliferous B. thuringiensis cells transformed with cry20Aa gene dramatically produced crystal inclusions. However, the intact 86-kDa Cry20Aa protein is highly labile, and it is rapidly degraded to polypeptides of 56 and 43 kDa. To increase expression of the cry20Aa gene, the p20 chaperonelike protein and the cyt1Aa promoter were utilized. While p20 did not increase Cry20Aa expression or stability, chimeric constructs in which the cry20Aa gene was under control of the cyt1Aa promoter overexpressed the Cry20Aa protein in acrystalliferous B. thuringiensis. The expressed Cry20Aa protein showed larvicidal activity against Aedes aegypti and Culex quinquefasciatus. However, the mosquitocidal activity was low, probably due to rapid proteolysis to inactive 56- and 43-kDa proteins.

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Selected References

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  1. Adams L. F., Visick J. E., Whiteley H. R. A 20-kilodalton protein is required for efficient production of the Bacillus thuringiensis subsp. israelensis 27-kilodalton crystal protein in Escherichia coli. J Bacteriol. 1989 Jan;171(1):521–530. doi: 10.1128/jb.171.1.521-530.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Arantes O., Lereclus D. Construction of cloning vectors for Bacillus thuringiensis. Gene. 1991 Dec 1;108(1):115–119. doi: 10.1016/0378-1119(91)90495-w. [DOI] [PubMed] [Google Scholar]
  3. Aronson A. I. The two faces of Bacillus thuringiensis: insecticidal proteins and post-exponential survival. Mol Microbiol. 1993 Feb;7(4):489–496. doi: 10.1111/j.1365-2958.1993.tb01139.x. [DOI] [PubMed] [Google Scholar]
  4. Bulla L. A., Jr, Bechtel D. B., Kramer K. J., Shethna Y. I., Aronson A. I., Fitz-James P. C. Ultrastructure, physiology, and biochemistry of Bacillus thuringiensis. Crit Rev Microbiol. 1980;8(2):147–204. doi: 10.3109/10408418009081124. [DOI] [PubMed] [Google Scholar]
  5. Chang C., Dai S. M., Frutos R., Federici B. A., Gill S. S. Properties of a 72-kilodalton mosquitocidal protein from Bacillus thuringiensis subsp. morrisoni PG-14 expressed in B. thuringiensis subsp. kurstaki by using the shuttle vector pHT3101. Appl Environ Microbiol. 1992 Feb;58(2):507–512. doi: 10.1128/aem.58.2.507-512.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Chen X. J., Curtiss A., Alcantara E., Dean D. H. Mutations in domain I of Bacillus thuringiensis delta-endotoxin CryIAb reduce the irreversible binding of toxin to manduca sexta brush border membrane vesicles. J Biol Chem. 1995 Mar 17;270(11):6412–6419. doi: 10.1074/jbc.270.11.6412. [DOI] [PubMed] [Google Scholar]
  7. Chen X. J., Lee M. K., Dean D. H. Site-directed mutations in a highly conserved region of Bacillus thuringiensis delta-endotoxin affect inhibition of short circuit current across Bombyx mori midguts. Proc Natl Acad Sci U S A. 1993 Oct 1;90(19):9041–9045. doi: 10.1073/pnas.90.19.9041. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Chungjatupornchai W., Höfte H., Seurinck J., Angsuthanasombat C., Vaeck M. Common features of Bacillus thuringiensis toxins specific for Diptera and Lepidoptera. Eur J Biochem. 1988 Apr 5;173(1):9–16. doi: 10.1111/j.1432-1033.1988.tb13960.x. [DOI] [PubMed] [Google Scholar]
  9. Dai S. M., Gill S. S. In vitro and in vivo proteolysis of the Bacillus thuringiensis subsp. israelensis CryIVD protein by Culex quinquefasciatus larval midgut proteases. Insect Biochem Mol Biol. 1993 Mar;23(2):273–283. doi: 10.1016/0965-1748(93)90008-g. [DOI] [PubMed] [Google Scholar]
  10. Delécluse A., Rosso M. L., Ragni A. Cloning and expression of a novel toxin gene from Bacillus thuringiensis subsp. jegathesan encoding a highly mosquitocidal protein. Appl Environ Microbiol. 1995 Dec;61(12):4230–4235. doi: 10.1128/aem.61.12.4230-4235.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Dervyn E., Poncet S., Klier A., Rapoport G. Transcriptional regulation of the cryIVD gene operon from Bacillus thuringiensis subsp. israelensis. J Bacteriol. 1995 May;177(9):2283–2291. doi: 10.1128/jb.177.9.2283-2291.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Donovan W. P., Dankocsik C., Gilbert M. P. Molecular characterization of a gene encoding a 72-kilodalton mosquito-toxic crystal protein from Bacillus thuringiensis subsp. israelensis. J Bacteriol. 1988 Oct;170(10):4732–4738. doi: 10.1128/jb.170.10.4732-4738.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Georghiou G. P., Wirth M. C. Influence of Exposure to Single versus Multiple Toxins of Bacillus thuringiensis subsp. israelensis on Development of Resistance in the Mosquito Culex quinquefasciatus (Diptera: Culicidae). Appl Environ Microbiol. 1997 Mar;63(3):1095–1101. doi: 10.1128/aem.63.3.1095-1101.1997. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Gill S. S., Cowles E. A., Pietrantonio P. V. The mode of action of Bacillus thuringiensis endotoxins. Annu Rev Entomol. 1992;37:615–636. doi: 10.1146/annurev.en.37.010192.003151. [DOI] [PubMed] [Google Scholar]
  15. Höfte H., Whiteley H. R. Insecticidal crystal proteins of Bacillus thuringiensis. Microbiol Rev. 1989 Jun;53(2):242–255. doi: 10.1128/mr.53.2.242-255.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Moran C. P., Jr, Lang N., LeGrice S. F., Lee G., Stephens M., Sonenshein A. L., Pero J., Losick R. Nucleotide sequences that signal the initiation of transcription and translation in Bacillus subtilis. Mol Gen Genet. 1982;186(3):339–346. doi: 10.1007/BF00729452. [DOI] [PubMed] [Google Scholar]
  17. Ross L. S., Gill S. S. Limited growth PCR screening of a plasmid library. Biotechniques. 1996 Sep;21(3):382-4, 386. doi: 10.2144/96213bm08. [DOI] [PubMed] [Google Scholar]
  18. Schnepf H. E., Whiteley H. R. Cloning and expression of the Bacillus thuringiensis crystal protein gene in Escherichia coli. Proc Natl Acad Sci U S A. 1981 May;78(5):2893–2897. doi: 10.1073/pnas.78.5.2893. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Thorne L., Garduno F., Thompson T., Decker D., Zounes M., Wild M., Walfield A. M., Pollock T. J. Structural similarity between the lepidoptera- and diptera-specific insecticidal endotoxin genes of Bacillus thuringiensis subsp. "kurstaki" and "israelensis". J Bacteriol. 1986 Jun;166(3):801–811. doi: 10.1128/jb.166.3.801-811.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Tinoco I., Jr, Borer P. N., Dengler B., Levin M. D., Uhlenbeck O. C., Crothers D. M., Bralla J. Improved estimation of secondary structure in ribonucleic acids. Nat New Biol. 1973 Nov 14;246(150):40–41. doi: 10.1038/newbio246040a0. [DOI] [PubMed] [Google Scholar]
  21. Waalwijk C., Dullemans A. M., van Workum M. E., Visser B. Molecular cloning and the nucleotide sequence of the Mr 28 000 crystal protein gene of Bacillus thuringiensis subsp. israelensis. Nucleic Acids Res. 1985 Nov 25;13(22):8207–8217. doi: 10.1093/nar/13.22.8207. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Ward E. S., Ellar D. J. Bacillus thuringiensis var. israelensis delta-endotoxin. Nucleotide sequence and characterization of the transcripts in Bacillus thuringiensis and Escherichia coli. J Mol Biol. 1986 Sep 5;191(1):1–11. doi: 10.1016/0022-2836(86)90417-1. [DOI] [PubMed] [Google Scholar]
  23. Ward E. S., Ellar D. J. Nucleotide sequence of a Bacillus thuringiensis var. israelensis gene encoding a 130 kDa delta-endotoxin. Nucleic Acids Res. 1987 Sep 11;15(17):7195–7195. doi: 10.1093/nar/15.17.7195. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Wu D., Federici B. A. A 20-kilodalton protein preserves cell viability and promotes CytA crystal formation during sporulation in Bacillus thuringiensis. J Bacteriol. 1993 Aug;175(16):5276–5280. doi: 10.1128/jb.175.16.5276-5280.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Yu Y. M., Ohba M., Gill S. S. Characterization of mosquitocidal activity of Bacillus thuringiensis subsp. fukuokaensis crystal proteins. Appl Environ Microbiol. 1991 Apr;57(4):1075–1081. doi: 10.1128/aem.57.4.1075-1081.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]

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