An Insect Toxin from Spores of Bacillus thuringiensis and Bacillus cereus

Somerville, H. J.; Pockett, Hazel V.

doi:10.1099/00221287-87-2-359

Cited by 43 publications

(18 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Effect of potassium ions on sporulation. Because B. thuringiensis 5-endotoxin production is correlated with sporulation (12,(30)(31)(32), the effect of potassium ions on the sporulation of the following Bacillus species was determined: B. thuringiensis subsp. kurstaki strain IK, B. cereus IFO 3466, B. megatherium IFO 1035, B. subtilis IFO 3007, B. licheniformis IFO 12199, B. circulans NRRL B3313, B. sphaericus ATCC 7055, and B. brevis IFO 3331 ( Table 7).…”

Section: Resultsmentioning

confidence: 99%

“…B. thuringiensis spores have a toxic protein resembling &-endotoxin (31). The toxin is solubilized from the spore surface by mercaptoethanol-urea and inactivated by crystal 5-endotoxin-specific serum (31). These findings indicate that sporulation and crystal formation are closely related.…”

mentioning

confidence: 83%

“…8-Endotoxin is an insecticidal crystal protein formed in Bacillus thuringiensis cells and used against Lepidoptera larvae (3). It contains large amounts of glutamic and aspartic acids (3) and is formed in correlation with sporulation (2,3,9,12,17,18,20,23,30,31,34,35). Young and Fitz-James (34) observed the simultaneous development of spores and crystals, and Lecadet and Dedonder (12) showed that the crystal protein was essentially formed during stages 3 and 4 of sporulation, before the acquisition of octanol resistance.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Formation of Crystalline δ-Endotoxin or Poly-β-Hydroxybutyric Acid Granules by Asporogenous Mutants of Bacillus thuringiensis

Wakisaka

Masaki

Nishimoto

1982

Appl Environ Microbiol

View full text Add to dashboard Cite

Parental strains and asporogenous mutants of Bacillus thuringiensis subspp. kurstaki and aizawai produced high yields of &-endotoxin on M medium, which contained 330 p.g of potassium per ml, but not on ST and ST-a media, each of which contained only 11 p.g of potassium per ml. On ST and ST-a media, refractile granules were formed instead. These granules had no insecticidal activity against silkworms and were isolated and identified as poly-p-hydroxybutyric acid. Supplementation of the potassium-deficient ST-a medium with 0.1% KH2PO4 (3.7 mM) led to the formation of crystalline 8-endotoxin. The replacement of KH2PO4 with equimolar amounts of KCl, KNO3, and potassium acetate or an equivalent amount of K2SO4 had a similar effect, whereas the addition of an equimolar amount of NaH2PO4 or NH4H2PO4 did not cause the endotoxin to form. An asporogenous mutant, B. thuringiensis subsp. kurstaki strain 290-1, produced 5endotoxin on ST-a medium supplemented with 3 mM or more potassium but formed only poly-3-hydroxybutyric acid granules on the media containing .1 mM potassium. These results clearly indicate that a certain concentration of potassium is essential for the fermentative production of 6-endotoxin by these isolates of B. thuringiensis. Manganese could not be substituted for potassium. Phosphate ions stimulated poly-,B-hydroxybutyric acid formation by strain 290-1. The sporulation of B. thuringiensis and several other Bacillus strains was suppressed on the potassium-deficient ST medium. This suggests that potassium plays an essential role not only in Bacillus cell growth and 5-endotoxin formation but also in sporulation.

show abstract

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 83%

mentioning

confidence: 99%

See 1 more Smart Citation

Formation of Crystalline δ-Endotoxin or Poly-β-Hydroxybutyric Acid Granules by Asporogenous Mutants of Bacillus thuringiensis

Wakisaka

Masaki

Nishimoto

1982

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…The existence of alkali activation (37) and its positive correlation with crystal production (5) have been reported by Benoit and colleagues. Similarly, the presence of crystal antigens on Cry ϩ spores has been reported many times previously (4,19,31,32). In particular, Aronson's laboratory has worked extensively on the surface localization of toxin (4) as it pertains to the differences observed between Cry ϩ and Cry Ϫ spores (2).…”

Section: Discussionmentioning

confidence: 57%

Bacillus thuringiensis HD-73 Spores Have Surface-Localized Cry1Ac Toxin: Physiological and Pathogenic Consequences

Du¹,

Nickerson²

1996

Appl Environ Microbiol

View full text Add to dashboard Cite

Spores from Cry ؉ strains of Bacillus thuringiensis bound fluorescein isothiocyanate-labeled antibodies specific for the 65-kDa activated Cry 1Ac toxin, whereas spores from Bacillus cereus and Cry ؊ strains of B. thuringiensis did not. The Cry ؉ spores could be activated for germination by alkaline conditions (pH 10.3), whereas Cry ؊ spores could not. Once the surrounding exosporia had been removed or permeabilized, Cry ؉ spores were able to bind the toxin receptor(s) from insect gut brush border membrane vesicle preparations, and their germination rates were increased ca. threefold in the presence of brush border membrane vesicles. A model is presented whereby in the soil the Cry toxins on the spore surface are protected by the exosporium while in the gut they are exposed and available for binding to the insect receptors. This model explains why the disulfide-rich C terminus of the cry genes is so highly conserved even though it is removed during the processing of the protoxin to the activated toxin. It also highlights the trade-off resulting from having Cry toxins located on the spore surface, i.e., decreased spore resistance versus enhanced insect pathogenesis.

show abstract

“…The organism is therefore fairly well characterized and it is generally accepted that most of the insecticidal properties are derived from the endotoxin (Faust, 1975) which is present both in a crystalline inclusion and in the spore coat (Delafield et al, 1968;Somerville & Pockett, 1975).…”

Section: Introductionmentioning

confidence: 99%

Virulence Factors in Bacillus thuringiensis: Purification and Properties of a Protein Inhibitor of Immunity in Insects

Sidén

Dalhammar

Telander

et al. 1979

Journal of General Microbiology

View full text Add to dashboard Cite

45We have previously shown that Bacillus thuringiensis subsp. alesti, serotype 3, produces two extracellular inhibitors of the immune system of Saturniid pupae (designated inhibitors A and B; Edlund et al., 1976). Starting from the culture supernatant of a new mutant of B. thuringiensis with a decreased extracellular proteolytic activity, we have now purified immune inhibitor A (InA). The procedure described consists of three steps : ultrafiltration, precipitation with ammonium sulphate and chromatography on hydroxylapatite. Purified InA gave a single band on polyacrylamide gel electrophoresis using either a gel concentration of 7.5 % (w/v) and reducing and denaturing conditions or a gradient gel and native conditions. In both cases the apparent molecular weight was 78000. A certain amount of proteolytic activity was always co-purified with InA but the two activities could be dissociated by heat or EDTA treatment. Antiserum against purified InA gave only one sharp precipitation band on immunodiffusion against InA with or without EDTA. InA inhibited the in vitro killing of Escherichia coli by immune haemolymph but did not affect the killing of Bacillus subtilis. InA was toxic for Drosophila when injected into the abdomen of adult male flies.

show abstract

An Insect Toxin from Spores of Bacillus thuringiensis and Bacillus cereus

Cited by 43 publications

References 12 publications

Formation of Crystalline δ-Endotoxin or Poly-β-Hydroxybutyric Acid Granules by Asporogenous Mutants of Bacillus thuringiensis

Formation of Crystalline δ-Endotoxin or Poly-β-Hydroxybutyric Acid Granules by Asporogenous Mutants of Bacillus thuringiensis

Bacillus thuringiensis HD-73 Spores Have Surface-Localized Cry1Ac Toxin: Physiological and Pathogenic Consequences

Virulence Factors in Bacillus thuringiensis: Purification and Properties of a Protein Inhibitor of Immunity in Insects

Contact Info

Product

Resources

About