Search results for "Bacillus"
showing 10 items of 774 documents
Antagonism of the endophytic Bacillus subtilis strain AG1 to fungal pathogens that cause tracheomycotic deterioration of wine wood
2008
Grapevine trunk diseases can determine considerable losses in the worldwide wine industry. Symptoms of wood diseases are dead spurs, arms, cordons and same times vine death, due to cankers in the vascular tissue (Pascoe, 2000). Recent research has also showed a recrudescence either of escadisease or decay by Verticilliumdahliae and the occurrence of new wood alterations (Botryosphaeriarhodina; Mugnai et al., 1999; Wood et al., 2005; Bonfiglioliet al., 2007). Last investigations, carried out in Sicilian vineyards on fungi associated with xilematic“esca”symptoms, revealed the occurrence of genus Bacillusin wood tissues. A spore-producer Gram-positive bacterial isolate, named AG1, was identifi…
Binding of Cyt1Aa and Cry11Aa Toxins of Bacillus thuringiensis Serovar israelensis to Brush Border Membrane Vesicles of Tipula paludosa (Diptera: Nem…
2007
ABSTRACT Bacillus thuringiensis serovar israelensis ( B. thuringiensis subsp. israelensis ) produces four insecticidal crystal proteins (ICPs) (Cry4A, Cry4B, Cry11A, and Cyt1A). Toxicity of recombinant B. thuringiensis subsp. israelensis strains expressing only one of the toxins was determined with first instars of Tipula paludosa (Diptera: Nematocera). Cyt1A was the most toxic protein, whereas Cry4A, Cry4B, and Cry11A were virtually nontoxic. Synergistic effects were recorded when Cry4A and/or Cry4B was combined with Cyt1A but not with Cry11A. The binding and pore formation are key steps in the mode of action of B. thuringiensis subsp. israelensis ICPs. Binding and pore-forming activity of…
Effect of Bacillus thuringiensis toxins on the midgut of the nun moth Lymantria monacha.
2000
Three steps of the proposed mode of action of Bacillus thuringiensis toxins have been studied in Lymantria monacha. We demonstrated that only the toxins that caused typical pathological changes in midgut epithelial cells and bound to the midgut brush border membrane were able to drastically reduce the midgut transepithelial voltage of the nun moth.
CARATTERIZZAZIONE METAGENOMICA di MICRORGANISMI E ORGANISMI DEL TERRENO PER UN LORO UTILIZZO COME AGENTI di LOTTA BIOLOGICA CONTRO NEMATODI FITOPARAS…
2014
La microflora della rizosfera riveste un ruolo fondamentale sia nella difesa che nello sviluppo e crescita delle piante. Molti studi hanno dimostrato inoltre che i nematodi sono in grado d’influenzarne la composizione. I batteri a loro volta producono una varietà di composti (antibiotici, nutrienti, esoenzimi e altre molecole segnale), in grado d’indurre ulteriori cambiamenti. L’obiettivo di questo lavoro è stato quello di studiare i cambiamenti nella biodiversità della microflora batterica di un terreno proveniente da un’azienda biologica, conseguenti all'introduzione sperimentale di larve di Meloidogyne incognita e al trattamento con un nematocida (fenamifos). Seguendo un approccio metage…
Update on the detection of beta-exotoxin in Bacillus thuringiensis strains by HPLC analysis.
2001
Aims: The current work aimed to study the presence of β-exotoxin by high-performance liquid chromatography (HPLC) in supernatant fluids from final whole cultures of the 69 type strains and 13 subtypes of Bacillus thuringiensis strains, as well as from some insecticidal strains. Methods and Results: Results from HPLC and bioassays with Ephestia kuhniella (Lepidoptera Pyralidae) were compared. Type I β-exotoxin was only detected in type strains representing serotypes H1, H9 and H10a,10b. Discrepancies between HPLC and bioassays were found in H8a,8b and some insecticidal strains, which suggests the occurrence of another soluble toxin different from type I β-exotoxin, possibly type II β-exotoxi…
Biological activity of Bacillus spp. evaluated on eggs and larvae of red palm weevil Rhynchophorus ferrugineus
2014
This study was conducted to characterize the Bacillus populations associated with dead Rhynchophorus ferrugineus, to develop a biological control for the red palm weevil. Dead adult beetles, collected throughout Sicily, were used for isolating internal and external spore forming bacteria (SFB) microbiota. The isolates, preliminarily allotted to the Bacillaceae family, were tested at 4 concentrations (103 to 106 CFU/mL) for their ability to inhibit hatching of eggs of R. ferrugineus and were used at 106 CFU/mL to monitor their insecticidal activity against 10 day-old larvae. Total amounts of SFB measured outside the skeleton and in the inners part of the beetles were 5.59-6.94 and 5.17-7.05 …
Indagini preliminari su bacilli sporigeni associati ad adulti di Punteruolo rosso e loro possibili impieghi in lotta biologica.
2009
E’ stata condotta un’indagine per isolare batteri sporigeni associati ad adulti morti di Rhynchophorus ferrugineus. La carica microbica riscontrata, sia quella superficiale che endogena, risulta essere elevata (107 UFC/gr). Gli isolati sono riconducibili al genere Bacillus. La produzione di cristalli parasporali, potenziali δ-endotossine, è stata utilizzata come parametro fondamentale per lo screening delle colture. All’attualità su un totale di 126 isolati solo 8, presentanti elevata produzione di esostrutture, sono stati sottoposti a caratterizzazione tassonomica. Gli isolati GC33 e GC76, identificati presuntivamente come Bacillus thuringiensis, sono stati saggiati alla concentrazione di …
Preliminary results on the interaction between Bacillus thuringensis and Red Palm Weevil.
2008
Study of two midgut aminopeptidases from Ostrinia nubilalis Hubner
2008
Aminopeptidases N (APNs) have been identified as Bacillus thuringiensis endotoxins receptor candidates in several Lepidopteran species. Employing the RACE PCR technique we obtained two complete cDNAs corresponding to two APNs expressed in the midgut of Ostrinia nubilalis larvae. One of the sequences was 3624 bp long, and the predicted protein was composed by 940 aminoacids, whereas the other cDNA was 3226 nucleotides long, leading a putative protein composed by 994 aminoacids. The in silico study of the sequences, showed in both proteins a signal peptide, a GPI-anchor domain, a zinc-binding region HEXXHX18E and a GAMEN motif, characteristic of the gluzincin aminopeptidases. Moreover, severa…
Effect of Bacillus thuringiensis on physiological rates of Mediterranean marine intertidal Mytilaster minimus (Mollusca, Bivalvia)
2010
The aim of the present research is to evaluate the impact of agricultural products in the marine environments. Indeed in a country such as Italy and in particularly Sicily where agricultural areas nearshore marine waters, predicting where, when and with what magnitude the impact of xenobiotics derived from agriculture is imperative. In this contest we use as model a biological product (Bacillus thuringiensis) in understanding its potential effects on non target species and on marine biodiversity. Bivalves are important elements of marine biodiversity and very often they play a role of ecosystem engineers in that many other species structurally depend on their presence. Moreover as they cons…