Translational machinery of the chaetognath <Emphasis Type="Italic">Spadella cephaloptera</Emphasis>: a transcriptomic approach to the analysis of cytosolic ribosomal protein genes and their expression

Background  

Chaetognaths, or arrow worms, are small marine, bilaterally symmetrical metazoans. The objective of this study was to analyse ribosomal protein (RP) coding sequences from a published collection of expressed sequence tags (ESTs) from a chaetognath (Spadella cephaloptera) and to use them in phylogenetic studies.     

Knockout of the folate transporter <Emphasis Type="Italic">folt-1</Emphasis> causes germline and somatic defects in <Emphasis Type="Italic">C. elegans</Emphasis>

Background  

The C. elegans gene folt-1 is an ortholog of the human reduced folate carrier gene. The FOLT-1 protein has been shown to transport folate and to be involved in uptake of exogenous folate by worms. A knockout mutation of the gene, folt-1(ok1460), was shown to cause sterility, and here we investigate the source of the sterility and the effect of the folt-1 knockout on somatic function.     

Expression of a novel gene, <Emphasis Type="Italic">gluP</Emphasis>, is essential for normal <Emphasis Type="Italic">Bacillus subtilis</Emphasis> cell division and contributes to glucose export

Background  

The Bacillus subtilis glucokinase operon was predicted to be comprised of the genes, yqgP (now named gluP), yqgQ, and glcK. We have previously established a role for glcK in glucose metabolism. In the absence of enzymes that phosphorylate glucose, such as GlcK and/or enzyme II^Glc, accumulated cytoplasmic glucose can be transported out of the cell. Genes within the glucokinase operon were not previously known to play a role in glucose transport. Here we describe the expression of gluP and its function in glucose transport.     

<Emphasis Type="Italic">Strongyloides stercoralis</Emphasis> infection in a Finnish kennel

Background  

Intestinal threadworm Strongyloides stercoralis is a parasite of dog, cat and primates that occurs worldwide being most prevalent in tropical and subtropical countries. The adult parasitic worm is about 2 mm long and slender. It possesses both parasitic and free-living lifecycles. The parasitic worms are females. Strongyloides stercoralis infects the host via percutaneous, peroral or transmammary transmission in addition to autoinfection. Clinical disease varies from inapparent to severe enteritis and pneumonia. The diagnosis is based on demonstration of larvae in fresh faeces, which is best made by Baermann technique.     

Chemically defined medium and <Emphasis Type="Italic">Caenorhabditis elegans</Emphasis>

Background  

C. elegans has been established as a powerful genetic system. Use of a chemically defined medium (C. elegans Maintenance Medium (CeMM)) now allows standardization and systematic manipulation of the nutrients that animals receive. Liquid cultivation allows automated culturing and experimentation and should be of use in large-scale growth and screening of animals.     

Characterization of Zur-dependent genes and direct Zur targets in Yersinia pestis

Background  

The zinc uptake regulator Zur is a Zn²⁺-sensing metalloregulatory protein involved in the maintenance of bacterial zinc homeostasis. Up to now, regulation of zinc homeostasis by Zur is poorly understood in Y. pestis.     

Molecular analysis of the emergence of pandemic <Emphasis Type="Italic">Vibrio parahaemolyticus</Emphasis>

Background  

Vibrio parahaemolyticusis abundant in the aquatic environment particularly in warmer waters and is the leading cause of seafood borne gastroenteritis worldwide. Prior to 1995, numerousV. parahaemolyticusserogroups were associated with disease, however, in that year an O3:K6 serogroup emerged in Southeast Asia causing large outbreaks and rapid hospitalizations. This new highly virulent strain is now globally disseminated.     

Screening of white‐rot fungi for bioprocessing of wheat straw into ruminant feed

Aim

In this study, the biological variation for improvement of the nutritive value of wheat straw by 12 Ceriporiopsis subvermispora, 10 Pleurotus eryngii and 10 Lentinula edodes strains was assessed. Screening of the best performing strains within each species was made based on the in vitro degradability of fungal‐treated wheat straw.

Methods and Results

Wheat straw was inoculated with each strain for 7 weeks of solid state fermentation. Weekly samples were evaluated for in vitro gas production (IVGP) in buffered rumen fluid for 72 h. Out of the 32 fungal strains studied, 17 strains showed a significantly higher (P < 0·05) IVGP compared to the control after 7 weeks (227·7 ml g^?1 OM). The three best Ceriporiopsis subvermispora strains showed a mean IVGP of 297·0 ml g^?1 OM, while the three best P. eryngii and L. edodes strains showed a mean IVGP of 257·8 and 291·5 ml g^?1 OM, respectively.

Conclusion

Ceriporiopsis subvermispora strains show an overall high potential to improve the ruminal degradability of wheat straw, followed by L. edodes and P. eryngii strains.

Significance and Impact of the Study

Large variation exists within and among different fungal species in the valorization of wheat straw, which offers opportunities to improve the fungal genotype by breeding.     

cAMP controls cytosolic Ca<Superscript>2+</Superscript> levels in <Emphasis Type="Italic">Dictyostelium discoideum</Emphasis>

Background  

Differentiating Dictyostelium discoideum amoebae respond upon cAMP-stimulation with an increase in the cytosolic free Ca²⁺ concentration ([Ca²⁺]_i) that is composed of liberation of stored Ca²⁺ and extracellular Ca²⁺-influx. In this study we investigated whether intracellular cAMP is involved in the control of [Ca²⁺]_i.     

A link of Ca<Superscript>2+</Superscript> to cAMP oscillations in <Emphasis Type="Italic">Dictyostelium</Emphasis>: the calmodulin antagonist W-7 potentiates cAMP relay and transiently inhibits the acidic Ca<Superscript>2+</Superscript>-store

Background  

During early differentiation of Dictyostelium the attractant cAMP is released periodically to induce aggregation of the cells. Here we pursue the question whether pulsatile cAMP signaling is coupled to a basic Ca²⁺-oscillation.     

The solution structure of ChaB,a putative membrane ion antiporter regulator from <Emphasis Type="Italic">Escherichia coli</Emphasis>

Background  

ChaB is a putative regulator of ChaA, a Na⁺/H⁺ antiporter that also has Ca⁺/H⁺ activity in E. coli. ChaB contains a conserved 60-residue region of unknown function found in other bacteria, archaeabacteria and a series of baculoviral proteins. As part of a structural genomics project, the structure of ChaB was elucidated by NMR spectroscopy.     

The role of iron uptake in pathogenicity and symbiosis in <Emphasis Type="Italic">Photorhabdus luminescens</Emphasis> TT01

Background  

Photorhabdus are Gram negative bacteria that are pathogenic to insect larvae whilst also having a mutualistic interaction with nematodes from the family Heterorhabditis. Iron is an essential nutrient and bacteria have different mechanisms for obtaining both the ferrous (Fe²⁺) and ferric (Fe³⁺) forms of this metal from their environments. In this study we were interested in analyzing the role of Fe³⁺ and Fe²⁺ iron uptake systems in the ability of Photorhabdus to interact with its invertebrate hosts.     

Crystal structure of nitrogen regulatory protein IIA<Superscript>Ntr</Superscript> from <Emphasis Type="Italic">Neisseria meningitidis</Emphasis>

Background  

The NMB0736 gene of Neisseria meningitidis serogroup B strain MC58 encodes the putative nitrogen regulatory protein, IIA^Ntr (abbreviated to NM-IIA^Ntr). The homologous protein present in Escherichia coli is implicated in the control of nitrogen assimilation. As part of a structural proteomics approach to the study of pathogenic Neisseria spp., we have selected this protein for structure determination by X-ray crystallography.     

Inhibition of hydrogen uptake in <Emphasis Type="Italic">Escherichia coli</Emphasis> by expressing the hydrogenase from the cyanobacterium <Emphasis Type="Italic">Synechocystis</Emphasis>sp. PCC 6803

Background  

Molecular hydrogen is an environmentally-clean fuel and the reversible (bi-directional) hydrogenase of the cyanobacterium Synechocystis sp. PCC 6803 as well as the native Escherichia coli hydrogenase 3 hold great promise for hydrogen generation. These enzymes perform the simple reaction 2H⁺ + 2e^- ↔ H₂ (g).     

Neuraminidase Inhibitors from marine‐derived actinomycete Streptomyces seoulensis

Aims

This work was performed to characterize new secondary metabolites with neuraminidase (NA) inhibitory activity from marine actinomycete strains.

Methods and Results

An actinomycete strain IFB‐A01, capable of producing new NA inhibitors, was isolated from the gut of shrimp Penasus orientalis and identified as Streptomyces seoulensis according to its 16S rRNA sequence (over 99% homology with that of the standard strain). Repeated chromatography of the methanol extract of the solid‐substrate culture of S. seoulensis IFB‐A01 led to the isolation of streptoseolactone ( 1 ), and limazepines G ( 2 ) and H ( 3 ). The structures of 1 – 3 were determined by a combination of IR, ESI‐MS, 1D (¹H and ¹³C NMR, and DEPT) and 2D NMR experiments (HMQC, HMBC, ¹H‐¹H COSY and NOESY). Compounds 1 – 3 showed significant inhibition on NA in a dose‐dependent manner with IC₅₀ values of 3·92, 7·50 and 7·37 μmol l^?1, respectively.

Conclusions

This is the first report of two new ( 1 and 2 ) and known ( 3 , recovered as a natural product for the first time in the work) NA inhibitors from the marine‐derived actinomycete S. seoulensis IFB‐A01.

Significance and Impact of the Study

The three natural NA inhibitors maybe of value for the development of drug(s) necessitated for the treatment of viral infections.