A screen for bacterial endosymbionts in the model organisms Tribolium castaneum, T. confusum, Callosobruchus maculatus, and related species

Reproductive parasites such as Wolbachia are extremely widespread amongst the arthropods and can have a large influence over the reproduction and fitness of their hosts. Undetected infections could thus confound the results of a wide range of studies that focus on aspects of host behavior, reproduction, fitness, and degrees of reproductive isolation. This potential problem has already been underlined by work investigating the incidence of Wolbachia infections in stocks of the model system Drosophila melanogaster. Here we survey a range of lab stocks of further commonly used model arthropods, focusing especially on the flour beetles Tribolium castaneum and Tribolium confusum, the cowpea weevil Callosobruchus maculatus and related species (Coleoptera: Tenebrionidae and Bruchidae). These species are widespread stored product pests so knowledge of infections with symbionts further has potential use in informing biocontrol measures. Beetles were assessed for infection with 3 known microbial reproductive parasites: Wolbachia, Rickettsia, Spiroplasma. Infections with some of these microbes were found in some of the lab stocks studied, although overall infections were relatively rare. The consequences of finding infections in these or other species and the type of previous studies likely to be affected most are discussed

A screen for bacterial endosymbionts in the model organisms Tribolium castaneum, T. confusum, Callosobruchus maculatus, and related species

Reproductive parasites such as Wolbachia are extremely widespread amongst the arthropods and can have a large influence over the reproduction and fitness of their hosts. Undetected infections could thus confound the results of a wide range of studies that focus on aspects of host behavior, reproduction, fitness, and degrees of reproductive isolation. This potential problem has already been underlined by work investigating the incidence of Wolbachia infections in stocks of the model system Drosophila melanogaster. Here we survey a range of lab stocks of further commonly used model arthropods, focusing especially on the flour beetles Tribolium castaneum and Tribolium confusum, the cowpea weevil Callosobruchus maculatus and related species (Coleoptera: Tenebrionidae and Bruchidae). These species are widespread stored product pests so knowledge of infections with symbionts further has potential use in informing biocontrol measures. Beetles were assessed for infection with 3 known microbial reproductive parasites: Wolbachia, Rickettsia, Spiroplasma. Infections with some of these microbes were found in some of the lab stocks studied, although overall infections were relatively rare. The consequences of finding infections in these or other species and the type of previous studies likely to be affected most are discussed

Molecular characterization of the malaria vector Anopheles barbirostris van der Wulp in Sri Lanka

Background: Anopheles barbirostris is a vector of malaria in Sri Lanka. The taxon exists as a species complex in the Southeast Asian region. Previous studies using molecular markers suggest that there are more than 4 distinct clades within the An. barbirostris complex in Southeast Asia. The present study characterizes Sri Lankan An. barbirostris using mtDNA cytochrome oxidase subunit I (COI) and ribosomal RNA internal transcribed spacer 2 (ITS2) gene sequences. Findings: DNA was extracted from morphologically identified An. barbirostris specimens from Sri Lanka, the COI and ITS2 regions amplified and their sequences analysed by comparison with other GenBank entries. Maximum likelihood trees suggested that Sri Lankan An. barbirostris constitute a different molecular type most closely related to clade I. Conclusions: Considering the uncorrected p distances between the clade I and Sri Lankan specimens it is fair to assume that the specimens collected from widely separated locations in Sri Lanka with morphology characteristic of An. barbirostris s.l. form a new molecular type with close resemblance to An. barbirostris s.s from Indonesia and Thailand

Antibiotic spider silk: site-specific functionalisation of recombinant spider silk using ‘click’- chemistry

The use of functionalised recombinant spider silk as a sustainable advanced biomaterial is currently an area of intense interest owing to spider silk’s intrinsic strength, toughness, biocompatibility and biodegradability. This paper demonstrates, for the first time, the site-specific chemical conjugation of different organic ligands that confer either antibiotic or fluorescent properties to spider silk. This has been achieved by the incorporation of the non-natural methionine analogue L-azidohomoalanine (L-Aha) using an E. coli methionine auxotroph and subsequent copper catalysed azide-alkyne cycloaddition (CuAAC) or ‘click chemistry’ functionalisation of 4RepCT3Aha. The 4RepCT3Aha protein can be modified either prior to, or post fibre formation increasing the versatility of this approach as demonstrated here by the formation of silk fibres bearing a defined ratio of two different fluorophores uniformly distributed along the fibres. Silk decorated with the fluoroquinone family broad spectrum antibiotic levofloxacin via a labile linker is shown to have significant antibiotic activity over a period of at least 5 days. The inherent low immunogenicity and pyrogenicity of spider silk should allow a diverse range of functionalised silks to be produced using these approaches that are tailored to applications including wound dressings and as tissue regeneration scaffolds

Parent participation in disadvantaged schools : moving beyond attributions of blame

Although facilitating community participation in disadvantaged schools can be difficult, this article argues that, given the structuring of schooling in contemporary western democracies, it is even more difficult than we might imagine. Drawing on Bourdieu, we attempt to elucidate the complex relations between schooling and socio·cultural contexts which can lead to inequalities of opportunity for parent participation in schooling and which work to maintain disadvantage for marginalised students. Recognitive justice, with its positive regard for social difference and centrality of social democratic processes, offers us another way of advancing this discussion beyond simplistic attributions of blame. In particular, a polities of recognition is concerned with opening up the processes of schooling to groups who often have been excluded. This article uses interview data from a small Australian secondary school located in a regional community with high welfare dependency and a large indigenous population