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Abstract: Insect pathogenic fungi like Beauveria bassiana have been developed as environmentally friendly biocontrol agents against arthropod pests. However, restrictive environmental factors, including solar ultraviolet (UV) radiation frequently lead to inconsistent field performance. To improve resistance to UV damage, we used Agrobacterium-mediated transformation to engineer B. bassiana with an exogenous tyrosinase gene. The results showed that the mitotically stable transformants produced larger amounts of yellowish pigments than the wild-type strain, and these imparted significantly increased UV-resistance. The virulence of the transgenic isolate was also significantly increased against the silkworm Bombyx mori and the mealworm Tenebrio molitor. This study demonstrated that genetic engineering of B. bassiana with a tyrosinase gene is an effective way to improve fungal tolerance against UV damage. [Copyright &y& Elsevier]

Abstract: To improve the present unsatisfactory UV-shielding and water-resistance properties of many emulsion-type latexes, in this study, poly(styrene-butylacrylate-acrylic acid) (PSBA)-grafted–silica (PSBA-g-silica) hybrid nanoparticles were firstly prepared by suspension–dispersion–polymerization. The resulting hybrid nanoparticles were then used to add into PSBA latex to fabricate PSBA nanocomposites. The influence of PSBA-g-silica hybrid nanoparticles on the interfacial adhesion, film morphology, thermodynamics properties, UV-shielding, water-resistance and mechanical performance of PSBA films were investigated systematically. Our results revealed that filling 1.5 wt% PSBA-g-silica hybrid nanoparticles resulted in significant improvement in interfacial adhesion properties, UV-shielding, water-resistance and mechanical properties. Fabricating the silica-based latex nanocomposite is an effective approach to develop the new emulsion-type paints and adhesives. [Copyright &y& Elsevier]

Abstract: The 60-kb pAD1 represents a large and widely disseminated family of conjugative, pheromone-responding, virulence plasmids commonly found in clinical isolates of Enterococcus faecalis. It encodes a hemolysin/bacteriocin (cytolysin) shown to contribute to virulence in animal models, and the related bacteriocin is active against a wide variety of Gram-positive bacteria. This review summarizes what is currently known about the molecular biology of pAD1, including aspects of its cytolytic, UV-resistance, replication, maintenance, and conjugative properties. [Copyright &y& Elsevier]