0000000000606374
AUTHOR
María D. Ferrandis
Characterization ofBacillus thuringiensisserovarbolivia(serotype H63), a novel serovar isolated from the Bolivian high valleys
The type strain Bacillus thuringiensis var. bolivia (serotype H63), isolated from the Bolivian high valleys, has been characterized at different levels. Its parasporal crystal has an unusual shape and it is composed of a protein of 155 kDa which shows two bands of 75 and 80 kDa after activation. Analysis by PCR shows the presence of cry1 genes, and amplification with specific primers gave products for cry1 E, cry1 D, cry4 A and cry4 B with sizes different to those expected. Immunoblotting tests showed positive reaction for Cry1 E, Cry3 A, Cry4 A and Cry11 A crystal proteins. The plasmid pattern revealed two large and two small plasmids. Toxicity tests were performed against 14 insects and a…
Environmental distribution and diversity of Bacillus thuringiensis in Spain.
Bacillus thuringiensis was isolated from 301 out of 1,005 samples collected in Spain from agricultural and non-cultivated soils, dust from stored products, and dead insects. Based on the production of parasporal crystals, 1,401 isolates were identified as B. thuringiensis after examining 11,982 B. thuringiensis-like colonies. We found a greater presence of B. thuringiensis in dust from grain storages than in other habitats. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the spore-crystal mixtures revealed diverse populations of B. thuringiensis which were differentiated in at least 92 distinct protein profiles. Serological identification also showed great diversity among the S…
Characterization of Bacillus thuringiensis ser. balearica (Serotype H48) and ser. navarrensis (serotype H50): two novel serovars isolated in Spain.
The novel strains of Bacillus thuringiensis PM9 and NA69, isolated from soil samples in Spain, were classified and characterized in terms of their crystal proteins, plasmid profile, cry genes content, and their toxicological properties against several species of Lepidoptera, Coleoptera, and Diptera. Both strains share morphological and biochemical characteristics with previously described B. thuringiensis strains, although their unique H antigens identify them as two new serotypes. Two new serovar names, B. thuringiensis serovar balearica (H serotype 48) and B. thuringiensis serovar navarrensis (H serotype 50) are proposed for the type strains PM9 and NA69, respectively.
Multi-Temporal Soil Salinity Assessment at a Detailed Scale for Discriminating Halophytes Distribution
A multi-temporal survey of soil salinity in a salt lake, recolonized by halophytes, was performed using electromagnetic induction (EMI) providing volume integrated values of soil apparent electrical conductivity (ECa). Inventories of plant communities were recorded according to the Braun-Blanquet method. In each of six areas monospecific with Suaeda vermiculata, Suaeda vera, Sarcocornia fruticosa, or Arthrocnemun macrostachyum, ECa was measured intensively in two seasons. Mean and range of ECa differ for each plant community. Soil was sampled in the six areas and analyzed for ion composition of the soil saturated paste extract. The electrical conductivity of the saturated paste extract (ECe…
Distribution of cryl, cryll and cryV Genes within Bacillus thuringiensis Isolates from Spain
Summary Using a PCR-based approach, a collection of 223 isolates of Bacillus thuringiensis from Spain was screened for the presence of cry genes belonging to three families. Genes from the cryI , cryII and cryV families were found in 54%, 42%, and 66% of the isolates, respectively. Only 23% of the isolates did not show the presence of any of the genes tested. Frequencies of these genes were compared in isolates from soil samples and from samples of cereal stores and mills, being this higher in the latter. Specific primers were used to detect cryIA(a), cryIA(b), cryIA(c), cryIA(d), cryIA(e), cryIB, cryIC, cryID, cryIE, cryIF and cryIG genes. Within the cryI family, the most frequent gene was…