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Draft genome sequence of the male-killing Wolbachia strain wBol1 reveals recent horizontal gene transfers from diverse sources

Background: The endosymbiont Wolbachia pipientis causes diverse and sometimes dramatic phenotypes in its invertebrate hosts. Four Wolbachia strains sequenced to date indicate that the constitution of the genome is dynamic, but these strains are quite divergent and do not allow resolution of genome diversification over shorter time periods. We have sequenced the genome of the strain wBol1-b, found

Influence of the virus LbFV and of Wolbachia in a host-parasitoid interaction.

Symbionts are widespread and might have a substantial effect on the outcome of interactions between species, such as in host-parasitoid systems. Here, we studied the effects of symbionts on the outcome of host-parasitoid interactions in a four-partner system, consisting of the parasitoid wasp Leptopilina boulardi, its two hosts Drosophila melanogaster and D. simulans, the wasp virus LbFV, and the

Microbial glycoside hydrolases for biomass utilization in biofuels applications

Renewable biomass is predicted to have the potential to meet at least a quarter of the world demand for transportation fuel, but to do so both terrestrial lignocellulosic as well as marine algal resources need to be efficiently utilized. In the processes where these biomasses are converted into different types of energy carriers (for example fuel-alcohols e.g. ethanol or butanol) microbial glycosi

Glycoside hydrolases for extraction and modifi cation of polyphenolic antioxidants

Antioxidants are important molecules that are widely used by humans, both as dietary supplements and as additives to different types of products. In this chapter, we review how flavonoids, a class of polyphenolic antioxidants that are often found in glycosylated forms in many natural resources, can be extracted and modifi ed using glycoside hydrolases (GHs). Glycosylation is a fundamental enzymati

Variations in plasmid content during Escherichia coli cultivations detected by on-line flow injection processing

An integrated flow injection process for analysis of intracellular components of microbes has been used to monitor plasmid content in Escherichia coli cultivations inoculated with cells subcultured in the presence or absence of ampicillin. The system allows sampling, sample handling, cell disruption, separation of intracellular components, and analysis in a semi-on-line mode of operation. The time

Deletion of a cytotoxic, N-terminal putative signal peptide results in a significant increase in production yields in Escherichia coli and improved specific activity of Cel12A from Rhodothermus marinus

The thermostable cellulase Cel12A from Rhodothermus marinus was produced at extremely low levels when expressed in Escherichia coli and was cytotoxic to the cells. In addition, severe aggregation occurred when moderately high concentrations of the enzyme were heat-treated at 65°C, the growth optimum of R. marinus. Sequence analysis revealed that the catalytic module of this enzyme is preceded by a

Cloning and sequence of a thermostable multidomain xylanase from the bacterium Rhodothermus marinus

The gene (xyn1) encoding a Rhodothermus marinus xylanase has been cloned and expressed in Escherichia coli. The gene comprises 5 different domains in an unusual combination. The cellulose binding domains (CBDs) encoded by xyn1 are repeated in tandem at the N-terminus and show similarity with the CBD family IV. The xyn1-gene is the first example encoding a CBD family IV in combination with a xylan

Evidence for substrate binding of a recombinant thermostable xylanase originating from Rhodothermus marinus

The xyn1 encoded 5 domain xylanase from the thermophilic bacterium Rhodothermus marinus binds specifically to xylan, β-glucan and amorphous but not crystalline cellulose. Our results show that the binding is mediated by the full length xylanase, but not by the catalytic domain only. Based on similarities concerning both predicted secondary structure and binding specificity found with one cellulose

Enzymatic specificity and hydrolysis pattern of the catalytic domain of the xylanase Xyn1 from Rhodothermus marinus

The catalytic domain of a xylanase from Rhodothermus marinus was produced in Escherichia coli. The catalytic domain belongs to glycosyl hydrolase family 10. The produced protein has a 22-amino acid leader peptide followed by a 411-amino acid truncated xylanase. The molecular mass was 48 kDa and the recombinant xylanase had a pI of 4.9. The pH and temperature optima for activity were determined to

Efficient production of truncated thermostable xylanases from Rhodothermus marinus in Escherichia coli fed-batch cultures

A cultivation strategy for the production of two truncated thermostable recombinant xylanases (Xyn1ΔN and Xyn1ΔNC) was developed. Fed-batch cultivations of Escherichia coli strain BL21(DE3) with a controlled exponential glucose feed led to high specific production of the recombinant proteins. Addition of complex nutrients (e.g. Tryptone Soya Broth (TSB)) to the media were shown to increase both th

Carbohydrate-binding modules from a thermostable Rhodothermus marinus xylanase : Cloning, expression and binding studies

The two N-terminally repeated carbohydrate-binding modules (CBM4-1 and CBM4-2) encoded by xyn10A from Rhodothermus marinus were produced in Escherichia coli and purified by affinity chromatography. Binding assays to insoluble polysaccharides showed binding to insoluble xylan and to phosphoric-acid-swollen cellulose but not to Avicel or crystalline cellulose. Binding to insoluble substrates was sig

Substrate-dependent production and some properties of a thermostable, α-galactosidase from Rhodothermus marinus

α-Galactosidase activity in Rhodothermus marinus is dependent on the composition of the growth media. A maximum of 46 μU g-1 cell dry weight was obtained using minimal medium with galactooligo- or polysaccharides as single carbon source. An enzyme hydrolysing both high and low molecular weight galacto-saccharides was partly purified from the cell fractions. The molecular weight was 200 kDa (native

Integrated flow-injection processing for on-line quantification of plasmid DNA during cultivation of E. coli

An integrated flow-injection processing (FIP) system for the quantification of plasmids during cultivation is described. The system performs on-line sampling, cell lysis, and quantification of plasmids in an integrated manner during cultivation of E. coli. The system was operated by using a miniaturized expanded-bed column which can be used for handling samples containing cells and cell debris wit

Marine Poly- and Oligosaccharides as Prebiotics

The marine environment can increase the global production of biomass. Interest in marine macroalgae and microorganisms has increased tremendously as a result of international agendas and market trends promoting sustainability as well as healthy food. Macroalgae and marine microorganisms contain unique poly- and oligosaccharides with different substitutions, e.g., sulfation or carboxylation. There

Tundra Trait Team : A database of plant traits spanning the tundra biome

Motivation: The Tundra Trait Team (TTT) database includes field-based measurements of key traits related to plant form and function at multiple sites across the tundra biome. This dataset can be used to address theoretical questions about plant strategy and trade-offs, trait–environment relationships and environmental filtering, and trait variation across spatial scales, to validate satellite data

Borderline Ovarian Tumors Share Familial Risks with Themselves and Invasive Cancers

Background: Borderline ovarian tumors (BOTs) are a subgroup of ovarian malignancies with low malignant potential. Very limited earlier data are available on familial clustering of BOTs with other cancers. We aim to explore histology-specific familial associations among BOTs and associations between BOTs and any invasive cancers.Methods: On the basis of 16.1 million individuals in the Swedish Famil

Contrasting prevalence of selection and drift in the community structuring of bacteria and microbial eukaryotes

Whether or not communities of microbial eukaryotes are structured in the same way as bacteria is a general and poorly explored question in ecology. Here, we investigated this question in a set of planktonic lake microbiotas in Eastern Antarctica that represent a natural community ecology experiment. Most of the analysed lakes emerged from the sea during the last 6000 years, giving rise to waterbod

Crop traits drive soil carbon sequestration under organic farming

Organic farming (OF) enhances top soil organic carbon (SOC) stocks in croplands compared with conventional farming (CF), which can contribute to sequester C. As farming system differences in the amount of C inputs to soil (e.g. fertilization and crop residues) are not enough to explain such increase, shifts in crop residue traits important for soil C losses such as litter decomposition may also pl