Insecticidal Activity of Bacillus thuringiensis Strains Isolated from Soil and Water

We attempted to search novel Bacillus thuringiensis strains that produce crystals with potential utility in plant protection and with higher activity than strains already used in biopesticide production. Seven B. thuringiensis soil and water isolates were used in the research. We predicted the toxicity of their crystals by cry gene identification employing PCR method. The isolate MPU B63 with interesting, according to us, genes content was used in evaluating its crystal toxicity against Cydia pomonella caterpillars. The strain MPU B63 was cultured from water sample and had cry1Ab, cry1B, and cry15 genes. The LC50 crystals of MPU B63 were compared to LC50 of commercial bioinsecticide Foray determined against C. pomonella (codling moth). The activity of MPU B63 inclusions against codling moth larvae was approximately 24-fold higher than that of Foray. The results are a promising introduction for further study evaluating the potential usefulness of isolate MPU B63 crystals in plant protection

Microbial identification for an effective biocleaning: the case study of the Santa Lucia alle Malve rupestrian church

Identifying the microbial community that lives on the lithic cultural heritage through phenotypic and genotypic approaches is fundamental for understanding the contribution of colonisers in biodeterioration and selecting the best cleaning solutions with environmentally-friendly products. This was done with the cultivable microbiota present on the internal walls of the Santa Lucia alle Malve (SLM) rock church, recognised by UNESCO as a World Heritage Site. The SLM church is in the Sasso Caveoso area (Matera, South Italy). It is fully excavated in the limestone rock. Numerous frescoes cover the internal surfaces, but the bacterial and fungal colonisation spoils its beauty. The results of this study clearly showed the predominance of bacteria of the phylum Firmicutes and precisely of the genus Bacillus, whose prevalence may be due to the specific environmental conditions, very similar in all sampling sites of the church, and to their ability to produce endospores. These dormant forms allow bacteria to survive in unfavourable conditions. The genotypic approach showed that the various Bacillus species isolated on the surfaces of the experimented church are closely related and similar but show a different phenotypic profile. This diversity of physiological and morphological traits reflects the potential complexity of the metabolomes present in the bacterial communities of the internal walls of the SLM and confirms the need to identify the colonisers correctly and proceed with a non-temporary bio-cleaning. The results of bio-cleaning using Solanum nigrum extracts were effective, but the durability of the treatment has yet to be verified

Microbial identification for an effective biocleaning: the case study of the Santa Lucia alle Malve rupestrian church

Identifying the microbial community that lives on the lithic cultural heritage through phenotypic and genotypic approaches is fundamental for understanding the contribution of colonisers in biodeterioration and selecting the best cleaning solutions with environmentally-friendly products. This was done with the cultivable microbiota present on the internal walls of the Santa Lucia alle Malve (SLM) rock church, recognised by UNESCO as a World Heritage Site. The SLM church is in the Sasso Caveoso area (Matera, South Italy). It is fully excavated in the limestone rock. Numerous frescoes cover the internal surfaces, but the bacterial and fungal colonisation spoils its beauty. The results of this study clearly showed the predominance of bacteria of the phylum Firmicutes and precisely of the genus Bacillus, whose prevalence may be due to the specific environmental conditions, very similar in all sampling sites of the church, and to their ability to produce endospores. These dormant forms allow bacteria to survive in unfavourable conditions. The genotypic approach showed that the various Bacillus species isolated on the surfaces of the experimented church are closely related and similar but show a different phenotypic profile. This diversity of physiological and morphological traits reflects the potential complexity of the metabolomes present in the bacterial communities of the internal walls of the SLM and confirms the need to identify the colonisers correctly and proceed with a non-temporary bio-cleaning. The results of bio-cleaning using Solanum nigrum extracts were effective, but the durability of the treatment has yet to be verified

Insecticidal activity of Bacillus thuringiensis Vip3A proteins against herbivorous pests of the order Lepidoptera

Wydział BiologiiBakterie Bacillus thuringiensis są chorobotwórcze względem różnych grup bezkręgowców: pierwotniaków, roztoczy, nicieni oraz owadów. Patogenność tych drobnoustrojów w stosunku do owadów związana jest z działaniem czynników wirulencji, z których najważniejsze to delta-endotoksyny Cry i Cyt oraz białka Vip. Toksyny te są jednak nieszkodliwe dla kręgowców m. in. dla ludzi. Obecnie toksyny Cry wchodzą w skład komercyjnych bioinsektycydów. W niniejszej pracy wyznaczono aktywność owadobójczą dwóch białek Vip (Vip3Aa1 i Vip3Aa35) względem owadów z rzędu Lepidoptera, będących szkodnikami lasów (Dendrolimus pini), sadów owocowych (Cydia pomonella) i upraw rolnych (Spodoptera exigua). Wartość LC50 została ustalona dla białek Vip w formie protoksyn oraz aktywowanych toksyn – stwierdzono zwiększoną toksyczność tej drugiej formy. Wykazano także wyższą aktywność Vip3Aa35 niż Vip3Aa1, pomimo dużego podobieństwa sekwencji aminokwasowej obydwu białek. Ponadto, określono toksyczność mieszaniny białek Vip i Cry, i stwierdzono synergizm w działaniu tych czynników wobec D. pini i S. exigua. Badania wykazały dużą skuteczność toksyn Vip oraz mieszaniny białek Vip i Cry w działaniu owadobójczym. Pod względem toksyczności przewyższają one wielokrotnie białka Cry stosowane do tej pory w komercyjnych bioinsektycydach. Wskazuje to na dużą potencjalną przydatność tych preparatów do produkcji biologicznych środków ochrony roślin o wysokiej aktywności owadobójczej i szerokim spektrum działania.B. thuringiensis are pathogens of various invertebrates: protists, mites, nematodes and insects. Insecticidal activity is attributed to virulence factors from which most important are Cry and Cyt delta-endotoxins as well as Vip proteins. These insecticidal factors are harmless towards vertebrates including humans. Nowadays Cry toxins are components of commercial bioinsecticides. In this work insecticidal activity of two Vip proteins (Vip3Aa1 i Vip3Aa35) was assessed towards lepidopteran insect pests of woodlands (Dendrolimus pini), orchards (Cydia pomonella) and crop fields (Spodoptera exigua). LC50 value was estimated for Vip protoxins and proteolytically activated toxins – the latter were more potent. It was demonstrated that Vip3Aa35 protein was more active towards insects than Vip3Aa1, despite high similarity of amino acid sequences between two toxins. Also in this work the toxicity of mixture containing both Vip and Cry proteins was evaluated – revealing synergism in insecticidal effect towards D. pini i S. exigua. In this work high insecticidal efficacy of Vip proteins as well as Vip and Cry mixtures was demonstrated. The potency of these factors surpass that of many Cry proteins used in commercial bioinsecticides. Vip toxins and mixtures containing Vip and Cry proteins have big potential usefulness in developing new bioinsecticides with higher potency and broad spectrum of susceptible insects

In vitro plant tissue cultures accumulate polyisoprenoid alcohols

In vitro cultivated plant cells and tissues were found to synthesize polyisoprenoids. Taxus baccata suspension cell cultures accumulated polyisoprenoids of the same pattern as the parental tissue; methyl jasmonate or chitosan treatment almost doubled their content. All the root cultures studied accumulated dolichols as predominant polyisoprenoids. Roots of Ocimum sanctum grown in vitro accumulated approx. 2.5-fold higher amount of dolichols than the roots of soil-grown plants. Dolichols dominated over polyprenols in all Triticum sp. tissues studied