Bacillus thuringiensis
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... CONTENTS -- ENVIRONMENTAL HEALTH CRITERIA FOR BACILLUS THURINGIENSIS -- PREAMBLE vii -- ABBREVIATIONS ... ... IDENTITY, BIOLOGICAL PROPERTIES, AND -- ANALYTICAL METHODS 6 -- 2.1 Identity 6 -- 2.1.1 Bacillus thuringiensis ... ... (Bt) 6 -- 2.1.2 Relationship between Bacillus thuringiensis and Bacillus cereus 6 -- 2.1.3 Crystal composition ... ... thuringiensis -- 3.3. ... ... EXPOSURE AND EFFECTS ON HUMANS 63 -- 7.1 Bacillus thuringiensis 63 -- 7.1.1 Experimental exposure of ...
Environmental health criteria, ISSN 0250-863X No. 217
XV, 105 s. ; 24 cm
- MeSH
- Bacillus thuringiensis patogenita MeSH
- biologická kontrola škůdců metody MeSH
- insekticidy chemie MeSH
- pracovní expozice MeSH
- vystavení vlivu životního prostředí MeSH
- Konspekt
- Veřejné zdraví a hygiena
- NLK Obory
- hygiena
- mikrobiologie, lékařská mikrobiologie
- environmentální vědy
- bakteriologie
- NLK Publikační typ
- publikace WHO
Thuricin 4AJ1, produced by Bacillus thuringiensis strain 4AJ1, showed inhibition activity against Bacillus cereus 0938 and ATCC 10987. It began to appear in the stationary phase and reached its maximum activity level of 209.958 U at 18 h against B. cereus 0938 and 285.689 U at 24 h against B. cereus ATCC 10987. Tricine-SDS-PAGE results showed that the partly purified thuricin 4AJ1 was about 6.5 kDa. The molecular weights of the known B. thuringiensis bacteriocins and the ones obtained by the two mainstream websites for predicting bacteriocins were inconsistent with the size of the thuricin 4AJ1, indicating that the bacteriocin obtained in this study may have a novel structure. Based on the biochemical properties, the thuricin 4AJ1 activities increased after treatment with proteinase K and lipase II, and were not affected by a-amylase, catalase, α-chymotrypsin VII and α-chymotrypsin II. It was heat tolerant, being active up to 90º C. In the pH 3-10 range, it maintained most of its activity. Finally, the sensitivity of the strain 4AJ1 to commonly used antibiotics was tested. In view of its stability and antibacterial activity, thuricin 4AJ1 may be applied as a food biopreservative.
- MeSH
- antibakteriální látky farmakologie MeSH
- Bacillus cereus účinky léků MeSH
- Bacillus thuringiensis chemie metabolismus MeSH
- bakteriociny chemie izolace a purifikace farmakologie MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- molekulová hmotnost MeSH
- potravinářská mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
A bacterial isolate (Mm2) of Melolontha melolontha was identified and characterized. Based on various morphological, physiological, biochemical and molecular characteristics, it was identified as Bacillus thuringiensis subsp. tenebrionis. This isolate was compared to the reference strains by electron microscopy, SDS-PAGE analysis, plasmid pattern, cry gene content and insecticidal activity. Cells of the isolate harbored flat square inclusions containing a protein component of approximately equal to65 kDa. After trypsin digestion of solubilized crystals, SDS-PAGE resolved a unique proteinase-resistant peptide of approximately equal to 50 kDa. Plasmid pattern showed similar bands to those of the reference strain, PCR analysis showed that the isolate has cry3 gene. Toxicity tests (against 5 coleopteran species) showed 80 % insecticidal activity against the larvae of M. melolontha. The isolate Mm2 may be valuable as biological control agent for M. melolontha and other coleopteran insects.
The aim of this study was to assess the diagnostic properties of the two selective plating media and a chromogenic medium for identification of Bacillus cereus. The 324 isolates were B. cereus (37%), Bacillus weihenstephanensis (45%) or Bacillus thuringiensis (18%), as identified by a new combination of techniques. All isolates were growing on mannitol-egg yolk-polymyxin agar (MYP), and they did not form acid from mannitol. However, a significant lower number of B. thuringiensis isolates did not show lecithinase activity. All isolates were also growing on polymyxin-egg yolk-mannitol-bromothymol blue agar (PEMBA); however, 11% isolates indicated that they did produce acid from mannitol, and 15% isolates did not show any lecithinase activity. Five of the isolates did not grow at all on the chromogenic agar, and 14 of the growing isolates were β-glucosidase negative. It is concluded that the two recommended selective plating media MYP and PEMBA for detection of B. cereus group bacteria both have their limitations for identification of some B. cereus, B. weihenstephanensis or B. thuringiensis. However, MYP is preferable compared to PEMBA. The chromogenic medium has its own advantages and limitations, and some of the limitations seem to be solved by incubation at 30°C instead of the recommended 37°C.
- MeSH
- Bacillus cereus klasifikace růst a vývoj izolace a purifikace metabolismus MeSH
- Bacillus thuringiensis klasifikace růst a vývoj izolace a purifikace metabolismus MeSH
- Bacillus klasifikace růst a vývoj izolace a purifikace metabolismus MeSH
- členovci mikrobiologie MeSH
- grampozitivní bakteriální infekce mikrobiologie MeSH
- kultivační média metabolismus MeSH
- lidé MeSH
- počet mikrobiálních kolonií metody MeSH
- potravinářská mikrobiologie MeSH
- půdní mikrobiologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
