Publications by authors named "Rouis Souad"

Cosmetics have been extremely popular throughout history and continue to be so today. Cosmetic and personal care products, including toothpaste, shampoo, lotions, and makeup, are typically made with petroleum-based surfactants. Currently, there is an increasing demand to enhance the sustainability of surface-active compounds in dermal formulations.

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-based products are key in the biopesticides market. strains Lip and BLB1 were isolated from Lebanese and Tunisian soils, respectively. These strains are highly toxic against lepidopteran larvae, .

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The economically important crop pest Ephestia kuehniella was tested at two stages of larval development for susceptibility to Bacillus thuringiensis Cry1Aa toxin. Bioassays showed that toxicity decreased during the development of larvae stage. In fact, Cry1Aa toxins from BNS3-Cry (pHT-cry1Aa) showed low toxicity against the first-instar larvae (L1) with a LC value of about 421.

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The basis of the different susceptibility of Ephestia kuehniella to the Cry1Aa and Cry1Ac δ-endotoxins from Bacillus thuringiensis kurstaki BNS3 was studied. Both toxins bound specifically to the BBMV of E. kuehniella.

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The Bacillus thuringiensis subsp. kurstaki strain MEB4 was previously found to be highly toxic to Ephestia kuehniella. SDS-PAGE analysis of the recombinant strain DH5α (pBS-cry2Aa-MEB4) showed that Cry2Aa-MEB4 delta-endotoxins were forming inclusion bodies, and were 2.

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Background: Cry2 proteins play an essential role in current Bacillus thuringiensis (Bt) applications and in the prevention of insect resistance to Cry1A toxins. This paper reports on the screening and characterisation of novel Bt strains harbouring effective cry2A-type genes and higher insecticidal activity to Ephestia kuehniella.

Results: A total of 29 native Bt strains were screened to search for the potent strain against E.

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BUPM95 is a Bacillus thuringiensis subsp. kurstaki strain producing the Vip3Aa16 toxin with an interesting insecticidal activity against the Lepidopteran larvae Ephestia kuehniella. Study of different steps in the mode of action of this Vegetative Insecticidal Protein on the Mediterranean flour moth (E.

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Chitinases have been successfully used in combination with Bacillus thuringiensis delta-endotoxins forming crystals in order to enhance their insecticidal activities. In this context, we opted for promoting the chitinase integration into these crystals. Thus, we engineered, for the first time, a fusion protein (CDF) consisting of the chitinase Chi255 and the carboxy-terminal half of Cry1Ac, both from B.

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LGMD (limb-girdle muscular dystrophy) and CMD (congenital muscular dystrophy) are two common forms of neuromuscular disorders which are distinguishable by their age of onset but with probably a similar underlying pathway. In the present study, we report immunohistochemical, Western-blot and genetic analyses in a large consanguineous Tunisian family with two branches, including seven patients sharing similar LGMD2 phenotype in one branch and one CMD patient in the other branch. Linkage analyses were compatible with the LGMD2A locus in one branch and the MDC1A (muscular dystrophy congenital type 1A) locus in the other branch.

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The study of 257 crystal-producing Bacillus thuringiensis isolates from bioinsecticide free soil samples collected from different sites in Tunisia, was performed by PCR amplification, using six primer pairs specific for cry1, cry2, cry3, cry4, and vip3A genes, by the investigation of strain plasmid pattern, crystal morphology and delta-endotoxin content and by the assessment of insecticidal activities against the lepidopteran insect Ephestia kuehniella. Based on plasmid pattern study, 11 representative strains of the different classes were subjected to morphological and molecular analyses. The comparison of the PFGE fingerprints confirmed the heterogeneity of these strains.

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Cry1Ia and Cry1Aa proteins exhibited toxicities against Prays oleae with LC(50) of 189 and 116 ng/cm(2), respectively. The ability to process Cry1Ia11 protoxin by trypsin, chymotrypsin and P. oleae larvae proteases was studied and compared to that of Cry1Aa11.

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Vegetative insecticidal protein (Vip) is a class of insecticidal proteins produced by many Bacillus thuringiensis strains during their vegetative growth stage. The vip3LB gene of B. thuringiensis strain BUPM95, which encodes a protein active against the Lepidoptera olive tree pathogenic insect Prays oleae, was cloned into pET-14b vector and overexpressed in Escherichia coli.

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The expression of recombinant antibodies in transgenic plants has been proved to be an efficient approach for large-scale production. However, the stability of these molecules and their accumulation level depend on their molecular properties and cellular targeting. The expression of single-domain antibody fragment (VH) can be advantageous since it offers small length, high expression, solubility and stability.

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BLB1 is a new Bacillus thuringiensis kurstaki strain, isolated from a Tunisian soil sample. Assay of toxicity of BLB1 crystal proteins resulted in an LC50 of 70.32 ng of toxin per mg of flour against third instar Ephestia kuehniella with confidence limits of (31.

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A comparative study of different steps in the mode of action of the individual Bacillus thuringiensis kurstaki BNS3 Cry1Aa and Cry1Ac delta-endotoxins on E. kuehniella larvae was performed in order to investigate the origin of the difference in the response of this larvae to each of the latter. Proteolytic activation was shown to be one of the main steps impaired in E.

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gyrB DNA fragments of seven Bacillus thuringiensis local collection family representatives were amplified by PCR and sequenced. Several differences in their corresponding sequences were evidenced. Both in silico and in vitro restriction maps of gyrB sequences and fragments respectively confirmed that EcoRI and Sau3AI could be used to differentiate between B.

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Unlike classical digestive lipases, the scorpion digestive lipase (SDL) has a strong basic character. The SDL activity's optimal pH, when using tributyrin or olive oil as substrate, was 9.0.

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Three single-chain variable fragment (scFv) antibodies recognizing the nuclear inclusion a (NIa) and capsid proteins of potato virus Y were obtained from two mouse derived hybridoma clones secreting, respectively, an anti-NIa (22-1) and an anti-coat protein (136-13) monoclonal antibodies. The first monoclonal antibody was able to inhibit in vitro the PVY polyprotein cleavage by blocking the NIa protease activity. The amplified scFv cDNAs were first inserted into the TOPO vector and then sequenced.

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The scorpion hepatopancreas consists of digestive diverticula and interstitial tissue. A digestive diverticulum is composed of two differentiated cell types: the secretory zymogene-like cells and the digestive cells which are the most abundant. The scorpion digestive lipase (SDL) has been previously purified from scorpion hepatopancreas, but its cellular localization has not yet been established.

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A synthetic gene encoding a single chain Fv fragment of an antibody directed against the nuclear inclusion a (NIa) protein of potato virus Y (PVY) was used to transform two commercial potato cultivars (Claustar and BF15). The NIa protease forms the nuclear inclusion body A and acts as the major protease in the cleavage of the viral polyprotein into functional proteins. Immunoblot analysis showed that most of the resulting transgenic plants accumulate high levels of the transgenic protein.

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Objective: To minimize the uncertainty in clinical diagnosis and improve the classification of 14 Tunisian patients belonging to 12 families and affected with congenital muscular dystrophy (CMD).

Methods: Fourteen patients belonging to 12 unrelated families originating from the south of Tunisia and affected with CMD were clinically examined between 1990 and 2001 in the neurology service of Chu Habib Bourguiba, Sfax, Tunisia. Immunohistochemical and western blot analyses were used to explore protein expression in muscular biopsies and homozygosity mapping using microsatellite markers for the genetic study.

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