Characterization of Cyt2Bc Toxin from
            <i>Bacillus thuringiensis</i>
            subsp.
            <i>medellin</i>

Juárez-Pérez, Víctor; Guerchicoff, Alejandra; Rubinstein, Clara P.; Delécluse, Armelle

doi:10.1128/aem.68.3.1228-1231.2002

Cited by 23 publications

(21 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Proteolytically activated Cyt2Ba is hemolytic in vitro [94,95] and exhibits lower toxicities against larvae of Culex, Aedes and Anopheles than Cyt1Aa [94] but higher than Cyt1Ab from Bt subsp. medellin [96].…”

Section: δ-Endotoxins Of Btimentioning

confidence: 99%

Bacillus thuringiensis subsp. israelensis and Its Dipteran-Specific Toxins

Ben‐Dov

2014

Toxins

187

149

View full text Add to dashboard Cite

Bacillus thuringiensis subsp. israelensis (Bti) is the first Bacillus thuringiensis to be found and used as an effective biological control agent against larvae of many mosquito and black fly species around the world. Its larvicidal activity resides in four major (of 134, 128, 72 and 27 kDa) and at least two minor (of 78 and 29 kDa) polypeptides encoded respectively by cry4Aa, cry4Ba, cry11Aa, cyt1Aa, cry10Aa and cyt2Ba, all mapped on the 128 kb plasmid known as pBtoxis. These six δ-endotoxins form a complex parasporal crystalline body with remarkably high, specific and different toxicities to Aedes, Culex and Anopheles larvae. Cry toxins are composed of three domains (perforating domain I and receptor binding II and III) and create cation-selective channels, whereas Cyts are composed of one domain that acts as well as a detergent-like membrane perforator. Despite the low toxicities of Cyt1Aa and Cyt2Ba alone against exposed larvae, they are highly synergistic with the Cry toxins and hence their combinations prevent emergence of resistance in the targets. The lack of significant levels of resistance in field mosquito populations treated for decades with Bti-bioinsecticide suggests that this bacterium will be an effective biocontrol agent for years to come.

show abstract

Section: δ-Endotoxins Of Btimentioning

confidence: 99%

Bacillus thuringiensis subsp. israelensis and Its Dipteran-Specific Toxins

Ben‐Dov

2014

Toxins

187

149

View full text Add to dashboard Cite

show abstract

“…More than a hundred different Cry toxins have been discovered and isolated from several B. thuringiensis subspecies. Unlike toxins in Cry family, Cyt toxins are produced by a minor group of B. thuringiensis mostly in subspecies that are toxic to Dipteran insects [5][6][7]. Unlike toxins in Cry family, Cyt toxins are produced by a minor group of B. thuringiensis mostly in subspecies that are toxic to Dipteran insects [5][6][7].…”

Section: Introductionmentioning

confidence: 99%

Co-expression ofBacillus thuringiensisCry4Ba and Cyt2Aa2 inEscherichia colirevealed high synergism againstAedes aegyptiandCulex quinquefasciatuslarvae

Promdonkoy

Panyim

2005

FEMS Microbiology Letters

View full text Add to dashboard Cite

Cry4Ba is a delta-endotoxin produced by Bacillus thuringiensis subsp. israelensis and Cyt2Aa2 is a cytolytic delta-endotoxin produced by B. thuringiensis subsp. darmstadiensis. Cry4Ba produced in Escherichia coli was toxic to Aedes aegypti larvae (LC(50)=140 ng ml(-1)) but virtually inactive to Culex quinquefasciatus larvae. Cyt2Aa2 expressed in E. coli exhibited moderate activity against A. aegypti and C. quinquefasciatus larvae with LC(50) values of 350 and 250 ng ml(-1), respectively. Co-expression of both toxins in E. coli dramatically increased toxicity to both A. aegypti andC. quinquefasciatus larvae (LC(50)=7 and 20 ng ml(-1), respectively). This is the first report to demonstrate that Cry4Ba and Cyt2Aa2 have high synergistic activity against C. quinquefasciatus larvae.

show abstract

“…The toxins in the other group, the Cyt toxins, are specifically toxic to Dipteran larvae including mosquito and blackfly larvae, in vivo. The toxins in this group also evidence cytolytic activity to a broad range of cells, including erythrocytes, in vitro (3)(4)(5)(6). The amino acid sequences of all Cyt toxins show a high degree of homology with each other (7), and therefore all of them should evidence similar 3D structures.…”

Section: Introductionmentioning

confidence: 99%

Amino acids at N- and C-termini are required for the efficient production and folding of a cytolytic γ-endotoxin from Bacillus thuringiensis

Thammachat

Pathaichindachote²,

Krittanai³

et al. 2008

BMB Reports

View full text Add to dashboard Cite

Bacillus thuringiensis Cyt2Aa toxin is a mosquito-larvicidal and cytolytic δ-endotoxin, which is synthesized as a protoxin and forms crystalline inclusions within the cell. These inclusions are solubilized under alkaline conditions and are activated by proteases within the larval gut. In order to assess the functions of the N-and C-terminal regions of the protoxin, several N-and C-terminal truncated forms of Cyt2Aa were constructed. It was determined that amino acid removal at the N-terminal, which disrupts the β1 structure, might critically influence toxin production and inclusion formation. The deletion of 22 amino acids from the C-terminus reduced the production and solubility of the toxin. However, the removal of more than 22 amino acids from the C-terminus or the addition of a bulky group to this region could result in the inability of the protein to adopt the proper folding. These findings directly demonstrated the critical roles of N-and C-terminal amino acids on the production and folding of the B. thuringiensis cytolytic δ-endotoxin. [BMB reports 2008; 41(11): 820-825]

show abstract

Characterization of Cyt2Bc Toxin from Bacillus thuringiensis subsp. medellin

Cited by 23 publications

References 19 publications

Bacillus thuringiensis subsp. israelensis and Its Dipteran-Specific Toxins

Bacillus thuringiensis subsp. israelensis and Its Dipteran-Specific Toxins

Co-expression ofBacillus thuringiensisCry4Ba and Cyt2Aa2 inEscherichia colirevealed high synergism againstAedes aegyptiandCulex quinquefasciatuslarvae

Amino acids at N- and C-termini are required for the efficient production and folding of a cytolytic γ-endotoxin from Bacillus thuringiensis

Contact Info

Product

Resources

About